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A systematic review and meta-analysis on the prevalence of dietary supplement use by military personnel

  • Joseph J Knapik1, 2, 4, 5Email author,
  • Ryan A Steelman2, 4,
  • Sally S Hoedebecke3,
  • Emily K Farina1,
  • Krista G Austin1, 4 and
  • Harris R Lieberman1
BMC Complementary and Alternative MedicineThe official journal of the International Society for Complementary Medicine Research (ISCMR)201414:143

DOI: 10.1186/1472-6882-14-143

Received: 23 October 2013

Accepted: 25 April 2014

Published: 2 May 2014

Abstract

Background

Although a number of studies have been conducted on the prevalence of dietary supplement (DS) use in military personnel, these investigations have not been previously summarized. This article provides a systematic literature review of this topic.

Methods

Literature databases, reference lists, and other sources were searched to find studies that quantitatively examined the prevalence of DS use in uniformed military groups. Prevalence data were summarized by gender and military service. Where there were at least two investigations, meta-analysis was performed using a random model and homogeneity of the prevalence values was assessed.

Results

The prevalence of any DS use for Army, Navy, Air Force, and Marine Corps men was 55%, 60%, 60%, and 61%, respectively; for women corresponding values were 65%, 71%, 76%, and 71%, respectively. Prevalence of multivitamin and/or multimineral (MVM) use for Army, Navy, Air Force, and Marine Corps men was 32%, 46%, 47%, and 41%, respectively; for women corresponding values were 40%, 55%, 63%, and 53%, respectively. Use prevalence of any individual vitamin or mineral supplement for Army, Navy, Air Force, and Marine Corps men was 18%, 27%, 25%, and 24%, respectively; for women corresponding values were 29%, 36%, 40%, and 33%, respectively. Men in elite military groups (Navy Special Operations, Army Rangers, and Army Special Forces) had a use prevalence of 76% for any DS and 37% for MVM, although individual studies were not homogenous. Among Army men, Army women, and elite military men, use prevalence of Vitamin C was 15% for all three groups; for Vitamin E, use prevalence was 8%, 7%, and 9%, respectively; for sport drinks, use prevalence was 22%, 25% and 39%, respectively. Use prevalence of herbal supplements was generally low compared to vitamins, minerals, and sport drinks, ≤5% in most investigations.

Conclusions

Compared to men, military women had a higher use prevalence of any DS and MVM. Army men and women tended to use DSs and MVM less than other service members. Elite military men appeared to use DSs and sport drinks more than other service members.

Keywords

Vitamins Minerals Multivitamins Vitamin C Vitamin E Calcium Iron Protein Creatine Sport drink

Background

Dietary supplements (DSs) are commercially available products that are consumed as an addition to the usual diet. DSs include ingredients such as vitamins, minerals, herbs (botanicals), amino acids, and a variety of other substances [1]. Marketing claims made for various DSs include the ability to improve overall health status, enhance cognitive or physical performance, increase energy, promote loss of excess weight, attenuate pain, and a variety of other favorable outcomes. The Dietary Supplement Health and Education Act of 1994 [2] established the regulatory framework for DSs in the United States (US). Since this act became law, US sales of DSs have increased from $4 billion in 1994 to $30 billion in 2011 [3, 4], an approximate 8-fold increase over 17 years.

Patterns of DS use may differ among distinctive subpopulations. Like athletes, military personnel often have occupational tasks that require intense and prolonged periods of physical activity. Like athletes, service members may use DSs that have purported ergogenic effects to enhance their occupational performance [59]. Unlike athletes, service members may be working in austere and hostile surroundings under extreme environmental conditions with high risk of injury. As a result, military personnel may use DSs that purportedly enhance health or performance under these conditions. In contrast, the general US population appears to consume DSs primarily for health reasons with only minor concern for performance enhancement [10, 11].

This paper presents a systematic literature review describing the prevalence of DS use in military personnel. No systematic review on this topic has previously been performed. Data collected by our group suggests that the use of DSs by military personnel may exceed that of civilian populations, and that selected subgroups within the military may have even higher DS use than the general military population [8, 12].

Methods

Literature searches were conducted in PubMed, Ovid MEDLINE (including OLDMEDLINE), OVID Healthstar, PsycINFO, Cumulative Index to Nursing and Allied Health Literature (CINAHL), the Defense Technical Information Center (DTIC), and publications from the National Institute of Medicine. No limitations were placed on the dates of the searches with the final search completed in January 2014. To assure that descriptors were all inclusive, we examined Medical Subject Headings for “military personnel” and “DSs” in PubMed. Largely as a result of this examination, keywords selected for the search included military personnel, soldier, sailor, airmen, marine, armed forces personnel, coast guard, submariners, Navy, and Air Force personnel combined with nutrition, DS, supplement, vitamin, mineral, amino acid, protein, herb, herbal, sport drink, sport bar, nutriceuticals, neutraceuticals, food supplements, and food supplementation. To find additional studies, the reference lists of the articles obtained were searched as was the literature database of an investigator with extensive experience with DSs. In several cases, authors were contacted to obtain information that was not included in the article.

Articles were selected for the review if they were:

  • Written in English,

  • Provided a quantitative assessment of the prevalence of DS use or prevalence could be calculated from data in the article, and

  • Participants were military personnel.

Studies were exclude if:

  • Participants were other than military personnel,

  • The study that did not allow separation of military personnel from others in the study,

  • Prevalence could not be calculated as a percent of the total sample in the study, or

  • The study that did not include specific DSs.

Data in which DSs were described by terms like “antioxidant”, “pro-performance”, “herbal supplement”, “ergogenics”, “thermogenics”, “bodybuilding”, and the like, were not included in this review because the type of DS was not specific. Exceptions were general categories of vitamins, minerals, sport drinks, sport bars, and energy drinks which were included because so many studies reported these.

Titles were first examined and abstracts were reviewed if the article appeared to involve military personnel and either nutrition or DSs. The full text of the article was retrieved if there was a possibility that DSs were included within the investigation. Quantitative prevalence data were obtained from the text of the article, from tables, or from graphs. If the data was in graphic form, prevalence was estimated from the vertical axis of the graph. Where multiple publications were found on a single study, all individual DS prevalences reported in any of the reports were included in the data extraction. The prevalence of a single type of DS reported in multiple publications from a single study was considered only once in the data extraction and analysis.

The methodological quality of the investigations was assessed using the technique of Loney et al. [13], which was developed specifically for rating prevalence investigations. Studies were graded on an 8-point scale which included assessments for sampling methods, sampling frame, sample size, measurement tools, measurement bias, response rate, statistical presentation, and description of subject sample. The 8 items were rated as either “yes” (1 point) or “no” (no point), based on specific criteria. Thus, the maximum possible score was 8. Three authors independently rated each of the selected articles. Following the independent evaluations, the reviewers met to examine the scores and to reconcile major differences. The average score of the three reviewers served as the methodological quality score. Scores were converted to a percent by dividing the average score for each study by 8 and multiplying by 100%.

The summary statistic derived from each study was the prevalence of specific DS use. This was calculated as the ∑ of individuals using the supplement/∑ of the entire sample × 100%. This expressed use prevalence as a percent of the sample. Data in some studies required recalculation because authors expressed the data as a percent of DS users rather than as a percent of the total sample. Tables were constructed, one containing methodology of each study, and the other containing the prevalences of the DSs reported in the studies. In the methodological table, the “response rate” was calculated as the subjects whose data were used in the investigation divided by the total number of subjects who were asked to participate. The response rates reported by some authors had to be recalculated because the authors reported the number of responses received without considering data that was discarded (e.g., incomplete or improperly completed questionnaires). The prevalence table included columns for the most commonly reported DSs in all articles. These included “any” DS, any vitamins or minerals, multivitamins/multiminerals (MVM), specific vitamins and minerals, creatine, proteins, amino acids, and specific herbal supplements. In cases where a specific supplement was not discussed in a study, the space in the prevalence table was left blank. In studies where at least 4% of the sample used a particular DS not contained in the table columns, that DS was listed in the last column of the prevalence table. Where possible, studies were separated by sex and specific military subgroups (e.g., Army, Navy, Air Force, Marine Corps, Army Rangers, Army Special Forces, Navy Special Operations). In a number of cases the study authors had not separated the data into these categories and so the data was presented as combined. Data were compiled by year to examine if any temporal trends could be discerned.

The Comprehensive Meta-Analysis Statistical Package, Version 2 (Biostat, Englewood NJ). was used to perform meta-analysis on specific groups and specific DSs where there were at least two studies and where subjects were asked about “current” DS use or use ≥1 time/week. A random model was used that involved providing the number of service members using the DS and those not using the DS to produce a summary prevalence estimate (SPE) with a summary 95% confidence interval (S95% CI) that represented the pooled results from the individual investigations. Homogeneity of the prevalence estimates from the studies was assessed using the Q statistic. To examine possible temporal trends, the prevalence of DSs reported in at least 3 studies were plotted by publication year. Curve fitting procedures were applied to these plots including linear, logarithmic, and second order polynomial fits.

Results

The search produced 2,930 potential publications. Figure 1 shows the number of publications included and excluded at each stage of the literature search. Thirty-three unique investigations in 38 publications met the review criteria. Seven reports were in government technical reports [1420], two were only in abstract form [21, 22], 9 were in an Institute of Medicine report on the use of DSs in military personnel [2331], and 20 reports were in peer-reviewed journal articles [59, 12, 3245]. Three individual studies had two reports each [15, 19, 25, 30, 32, 38] and one produced three relevant publications [8, 41, 42].
https://static-content.springer.com/image/art%3A10.1186%2F1472-6882-14-143/MediaObjects/12906_2013_Article_1732_Fig1_HTML.jpg
Figure 1

Records included and excluded at each stage of literature review.

Two studies that involved DS use in military groups were excluded. One study of repatriated Vietnam prisoners-of- war was not included because of the unusual circumstances and because the vitamin intake was not voluntary in some cases [46]. Also excluded was one study that asked physicians about DSs reported by patients, as opposed to participants self-reporting their DS use [47].

Table 1 shows the subjects and methods used to obtain data from the 33 unique investigations. Most studies involved US service members, but two studies were conducted among deployed British soldiers [7, 40] and one in Macedonian Special Operations Soldiers [45]. Among the US service members, several studies examined elite military service members including Army Rangers [5, 22, 27, 30, 38], Army Special Forces [12, 28], and Navy Sea, Air, Land (SEAL) personnel [36]. Other studies involved general samples of Army soldiers [6, 8, 14, 16, 23, 26], Air Force personnel [17, 31], Navy [37] and Marine Corps personnel [9, 18, 37], Marine and Air Force trainees [20, 36, 39], senior military officers [29], military officers in training [15, 35], men initiating training to become Ranger and Special Forces soldiers [33], and multiple service groups [19, 24, 25, 34, 43, 44].
Table 1

Methods in investigations of DS use by military personnel

Study

Subjects

Methods for collecting supplement information

Reporting timeframe

Response rate (%) - proportion of population participating in investigation

Methodological quality score (%)

Carlson et al. [14]

43 ♂ US Army senior non-commissioned officers

Questionnaire with items on DS use

Current Use

86

75

Klicka et al. [15]

119 ♂ & 86 ♀ cadets at the US Military Academy at West Point NY

7-day dietary record with interview

Use over 7 days

Not provided

38

Schneider et al. [21]

91 ♂ US Navy SEAL personnel

Questionnaire focused on DS use

Current Use

Not provided

25

Kennedy and Arsenault [33]

2,215 ♂ US Army soldiers entering Special Forces and Ranger training

Questionnaire focused on DS use

Current use, ≥ 1 time/wk, within last 3 months

99

66

Warber et al. [16]

2,547 ♂ & 494 ♀ US Army soldiers from 32 Army installations world-wide

Questionnaires with items on DSs

Current use ≥1 time/wk

Not provided

59

McGraw et al. [22]

367 ♂ US Army Rangers

Questionnaire focused on DS use

Use in past 6 months

Not provided

41

Sheppard et al. [34]

102 ♂ & 31 ♀ US service members using health clubs

Questionnaire focused on creatine and use of other DSs

Current use

70

66

Arsenault & Cline [35]

50 ♀ officers in Basic Officer Training

7-day dietary record with interview

Use over 7 day period

Not provided

42

Stevens and Olsen [36]

439 ♂ & 60 ♀ US marine or AF basic trainees

Questionnaire focused on ergogenic DS use

Any use in lifetime

91

91

Shanks [17]

224 ♀ active duty US AF women

Questionnaire focused on herbal therapy

Use in the last 2 years

45

75

Bovill et al. [12]

119 ♂ US Army Special Forces soldiers

Questionnaire on nutrition and DS use

Current use

Not provided

29

Deuster et al. [5]

38 ♂ US Army Rangers at Fort Bragg, North Carolina

General health questionnaire with items on DSs

Daily Use

Not provided

29

Brasfield [6]

750 ♂ & 124 ♀ US Army soldiers from 16 Army posts

Questionnaire focused on DS use

Current use ≥1 time/wk

58

59

Castillo et al. [18]

1,326 ♂ & 120 ♀ US marines at Camp Pendleton, California

Questionnaire (Marine Health Behavior Survey) with items on DSs

Use in last year

85

59

Bray et al. [19, 25]

12,119 ♂ & 4,027 ♀ US quad-service members (23% Army; 29% Navy, 21% Marine Corps, 28% AF)

Questionnaire with items on DS use

Current use ≥1 time/wk in last year

53

88

Smith et al. [37]

1,009 ♂ and 296 ♀ US Navy and Marine Corps personnel (72% Navy, 22% Marine Corps, 6% Navy Reserve/Guard)

Questionnaire with items on DS use

Use in past year

35

79

Johnson et al. [30, 38]

294 ♂ US Army Rangers

Questionnaire focused on DS use

Current Use

39

41

Corum [23]

3,789 ♂ & 1,146 ♀ US Army soldiers assigned in Europe

Questionnaire focused on DS use

Current use

Not provided

38

French [24]

376 US service members, active duty, National Guard, or reserves

On-line questionnaire focused on DS use

Use in past 3 months

60

38

Lieberman [29]

284 ♂ & 31 ♀ US senior military officers at the US Army War College, all services

Questionnaire focused on DS use

Use ≥ 1 time/wk

Not provided

34

Lieberman [27]

768 ♂ US Army Rangers

Questionnaire focused on DS use

Use ≥1 time/wk

Not provided

25

Lieberman [28]

152 ♂ US Army Special Forces soldiers

Questionnaire focused on DS use

Use ≥1 time/wk

Not provided

29

Lieberman [26]

444 ♂ & 40 ♀ US Army soldiers

Questionnaire focused on DS use

Use ≥1 time/wk

80

46

Thomasos 2008 [31]

10,985 US AF personnel at 27 major installations

Questionnaire focused on DS use

Current use

Not provided

38

Young and Stephens [39]

236 ♂ & 83 ♀ US Marine Corps recruits entering basic training

Questionnaire focused on DS use

Use at any time in past

65

54

Boos et al. [7]

889 ♂ & 128 ♀ UK Soldiers deployed in Basra, Iraq

Questionnaire focused on DS use

Current Use

66

66

Lieberman et al. [8, 41, 42]

859 ♂ &131 ♀ US Army soldiers from 11 locations including two overseas; 17 ♂ Special Forces soldiers

Questionnaire focused on DS use

Use ≥1 time/wk in last 6 months

~80

71

Wells & Webb [20]

197 US AF trainees in Tactical Air Control Party training

Questionnaire with items on DSs

Current Use

Not provided

41

Boos et al. [40]

78 ♂ & 9 ♀ UK soldiers deployed in Afghanistan

Questionnaire focused on DS use

Current use

58

29

Jacobson et al. [43]

72,718 ♂ & 33,980 ♀ US service members (active & reserve) enrolled in the Millennium Cohort Study

Questionnaire including item on DS use

Use in last 12 months

68

88

Toblin et al. [44]

988 ♂ US Army soldiers and marines deployed to Afghanistan

Questionnaire including item on energy drinks

Daily Use

79

71

Kjertakov et al. 2013 [45]

132 ♂ Macedonian Special Operations soldiers

Questionnaire focused on DS use

Use in last 3 months

Not provided

41

Cassler et al. [9]

310 ♂ & 19 ♀ US marines deployed in Afghanistan (Camp Leatherneck)

Questionnaire focused on DS use

Use in last 30 days

Not provided

38

Abbreviations: ♂ = men, ♀ = women; DS(s) = dietary supplement(s); US = United States; UK = United Kingdom; AF = Air Force; SEAL = Sea, Air, Land (US Navy special operations personnel); wk = week; NY = New York.

In most unique studies (n = 31), the data were collected by having service members self-report their DS use on questionnaires. Most of the questionnaires were specifically designed to obtain information on DSs and focused on this topic [69, 12, 17, 2124, 2631, 33, 34, 36],[3842, 45]. Other studies obtained DS information from questionnaires that had items on DS use but were designed for more general purposes, often to collect a range of nutritional measures [5, 14, 16, 1820, 25, 37, 43, 44]. Two unique investigations obtained DS information from 7-day food records complimented with interviews by dietitians [15, 32, 35].

The reporting timeframe differed among studies. In many investigations, service members reported DS use ≥1 time/week, or these data could be calculated from the information provided in the articles [6, 8, 16, 19, 2529, 33, 41, 42]. Other studies examined current use but did not clearly define the frequency of use [7, 12, 14, 23, 24, 30, 31, 34],[38, 40]. In other studies, service members reported use in the last 7 days [15, 32, 35], last month [9], last 3 months [24, 45], last 6 months [22], last 12 months [18, 37, 43], or last two years [17]. Two studies examined the lifetime prevalence of DS use in Marine and Air Force basic trainees [36, 39]. Two studies reported daily use [5, 44] and in one study the reporting timeframe was not stated [21].

The response rate was not provided in 15 unique studies [5, 9, 12, 15, 16, 2023, 2729, 31],[35, 45]. In the 18 other unique investigations, the response rates ranged from 35% [37] to 99% [33] with only 10 unique investigations having response rates ≥66% [7, 8, 14, 18, 26, 33, 34, 36],[43, 44].

Rating from the methodological quality reviews ranged from 25% to 91% of available points, with an average ± standard deviation rating of 52 ± 20%. Only 8 studies (24%) had a rating of 70% or better. Several studies were only reported in an Institute of Medicine publication on DS use in the military [48] and received relatively lower scores because of the lack of detail provided [23, 24, 2629, 31]. The study by Bray et al. [19] was particularly well conducted in that the investigators attempted to collect a random sample of the entire military and clearly outlined their sampling methods, sampling frame, questionnaire, and results.

Table 2 shows available data on the prevalence of DS use by service members. Twenty-six unique investigations provided the prevalence of “any” DS use [59, 12, 15, 1822, 24, 2629, 31, 33],[35, 36, 3840, 43, 45] and 17 reported on multivitamin use [69, 12, 16, 19, 2124, 2629, 33, 45]. Only 10 unique investigations reported on specific vitamins and mineral supplements [6, 12, 2224, 26, 28, 29, 33, 45] and 7 reported on specific herbal supplements [6, 17, 23, 29, 33, 39, 45]. Nineteen unique investigations reported on supplementation with creatine [57, 12, 18, 2124, 2628, 33, 34, 36],[3840, 45] and 20 reported on amino acid and/or protein supplements [59, 12, 16, 2124, 2628, 33, 34, 3840],[45]. Finally, supplementation with sport drinks were reported in 11 investigations [5, 8, 12, 21, 23, 2629, 39, 45], sport bars in 10 studies [8, 12, 16, 2123, 2628, 33], and energy drinks in 3 investigations [8, 9, 44]. None of the studies identified the use prevalence of specific brands of MVM, vitamins, minerals, amino acids, proteins, botanicals, sport drinks or sport bars.
Table 2

Prevalence of dietary supplement use by military personnel

Study

Subjects

Proportion of entire sample reporting use (%)

  

Any DS Use

Any Vit (V), Minl (M), or Vit/Minl (VM) Suppl

MV or MVM Suppl

Vit A

Vit B or B Cmpx

Vit C

Vit D

Vit E

Fe

Ca

Zn

Creatine

Amino acids (A), Prot (P), or Amino acids & Prot (AP)

Ginkgo Biloba

Ginseng

Sport drink

Sport bar

Other DSs in study

Carlson et al. [14]

43 ♂ US Army senior non-commissioned officers

 

VM-7

                

Klicka et al. [15, 32]

119 ♂ cadets at USMA

14

                 

86 ♀ cadets at USMA

35

                 

Schneider et al. [21]

91 ♂ SEAL personnel

78

 

26

        

32

AP-12

  

19

40

 

Kennedy & Arsenault [33]

2,215 ♂ US Army Special Forces and Rangers in training

64

 

30

5b

3

13

 

6

3

5

3

15

A-9a

 

5

 

11

Cr-4

Warber et al. [16]

2,547 ♂ US Army Soldiers

 

V-18

24

         

A-10

   

8

 

494 ♀ US Army Soldiers

 

V-24

35

         

A-4

   

3

 

McGraw et al. [22]

367 ♂ US Army Rangers

36

 

16

  

7

     

19

AP-14

   

6

 

Sheppard et al. [34]

102 ♂ & 31 ♀ US military health clubs users

 

V-65 M-47

         

29

P-45

    

Caf-32

Arsenault & Cline [35]

50 ♀ US officers in Basic Officer Training

38

                 

Stevens & Olsen [36]

439 ♂ & 60 ♀ US Marine Corps or AF basic trainees

41

          

23

     

AD-8

Shanks [17]

224 ♀ US active duty AF women

             

5

5

  

Eph-5; Gar-4; Ech-5; SJW-5

Bovill et al. [12]

119 ♂ US Army Special Forces soldiers

90

 

55

  

20

 

12

 

9

 

18

P-24

  

71

52

 

Deuster et al. [5]

38 ♂ US Army Rangers

82

          

13

P-24

  

82

 

Eph-13

Brasfield [6]

750 ♂ US Army soldiers

59

 

33

8

7c

17

 

10

7

12

3

16

A-6

6

14

  

K-7; Vit B6-6; CP-4; Eph-13; Gar-7; Ech-4

124 ♀ US Army soldiers

70

 

40

7

15

7

12

14

  

6

Castillo et al. [18]

1,326 ♂ & 120 ♀ US marines

54

VM-13

         

18

     

Eph-24; AD-5

Bray et al. [19]

12,119 ♂ US quad-service members

58

VM-25

43

               

4,027 ♀ US quad-service members

71

VM-37

56

               

2,818 ♂ Army Soldiers

55

VM-24

38

               

821 ♀ Army Soldiers

66

VM-34

50

               

3,341 ♂ Navy Sailors

60

VM-27

46

               

1,286 ♀ Navy Sailors

71

VM-36

55

               

2,767 ♂ Marines

61

VM-24

41

               

589 ♀ Marines

71

VM-33

53

               

3,193 ♂ AF Airmen

60

VM-25

47

               

1,331 ♀ AF Airmen

76

VM-40

63

               

Smith et al. [37]

1,009 ♂ and 296 ♀ US Navy and Marine Corps personnel

 

V-12

                

Johnson et al. [30, 38]

294 ♂ US Army Rangers

56

          

26

P-35 A-4

     

Corum [23]

3,789 ♂ & 1,146 ♀ US Army Soldiers assigned in Europe

  

34

13

 

24

  

14

19

 

13

P-14

4

7

43

17

K-12; Ech-4; Gar-5; Vit B6-12; Caf-18

French [24]

376 US service members

69

 

57

 

8

 

3

9

 

13

 

6

P-14 A-4

    

Ω3FA-9; GlCon-7; FSO-4

Lieberman [29]

284 ♂ US senior military officers

71

 

39

5

6

17

 

22

 

5

   

5

 

10

 

Gar-6

31 ♀ US senior military officers

81

 

52

16

36d

29

 

32

 

32

       

Mg-13

Lieberman [27]

768 ♂ US Army Rangers

81

 

23

        

19

PA-18

  

41

6

AD-7

Lieberman [28]

152 ♂ US Army Special Forces Soldiers

65

 

32

  

11

 

7

   

16

P-16

  

36

15

AD-6

Lieberman [26]

444♂ US Army Soldiers

55

 

30

5

 

13

5

6

 

6

 

5

P-13

  

20

5

 

40 ♀ US Army Soldiers

70

 

28

 

23e

13

8

8

10

15

  

P-8

  

28

  

Thomasos [31]

10,985 US AFpersonnel

69

                 

Young & Stephens [39]

236 ♂ & 83 ♀ US Marine Corps recruits entering basic training

50

V-26

        

3

26

P-43

6

 

36

 

NO-16;Glu-16; GlCon-9

Boos et al. [7]

889 ♂ & 128 ♀ UK Soldiers deployed in Iraq

32

 

2

        

13

P-19 A-18

    

Caf-4

Lieberman et al. [8, 41, 42]

859 ♂ US Army Soldiers

53f

VM-17

37

         

PA-20

  

23

6

ED-41

131 ♀ US Army Soldiers

57f

VM-23

41

         

PA-9

  

24

4

ED-25

17 ♂ US Special Forces Soldiers

77 f

VM-64

64

         

PA-47

  

32

7

 

Wells & Webb [20]

197 US AF trainees in Tactical Air Control Party training

73

                 

Boos et al. [40]

78 ♂ & 9 ♀ UK Soldiers deployed in Afghanistan

40

          

14

PA-34

    

CP-15

Jacobson et al. [43]

72,718 ♂ and 33,980 ♀ US service members (active & reserve)

47

                 

Toblin et al. [44]

988 ♂ deployed US Army soldiers and marines

                 

ED-45

Kjertakov et al. [45]

78 ♂ Macedonian Rangers

64

 

47

13

14

44

 

9

8

18

3

3

P-8A-5

 

0

15

 

VitB6-14; Vit B12-6; Mg-10

54 ♂ Macedonian Special Forces Soldiers

70

 

54

13

24

54

 

15

13

11

2

2

P-7 A-11a

 

2

15

 

VitB6-13; Vit B12-9; Mg-16; Se-4; Glu-4

Cassler et al. [9]

310 ♂ US marines deployed in Afghanistan

72

 

47

         

P-64

    

ED-42

 

19 ♀ US marines deployed in Afghanistan

42

                 

Abbreviations: ♂ = men, ♀ = women; DS = dietary supplement; Vit or V = vitamin; Minl or M = mineral; VM = vitamin and/or mineral; MV = multivitamin; MVM = multivitamin/multimineral; A = amino acid; Prot or P = protein; AP = amino acids and protein; cmpx = complex; Fe = iron; Ca = calcium; Zn = zinc; Mg = magnesium; Cr = chromium; Se = selenium; K = potassium; Caf = caffeine; ED = energy drink; Gar = garlic; AD = androstenedione; Eph = ephedrine; FSO = flax seed oil; Glu = glutamine; Ech-echinacea; SJW = Saint John’s Wort; Ω3FA = omega-3-fatty acid; GlCon = glucosamine chondroitin; NO = nitric acid; CP = chromium picolinate; AF = Air Force; SEAL = Sea, Air, Land (US Navy special operations personnel); UK = United Kingdom; USMA = United State Military Academy.

Notes: aCombines amino acids and branched chain amino acids; bCombines β-carotene and Vit A; cCombines B-complex, folic acid, and pantothenic acid; dCombines folate, B-complex, and Vit B6; eCombines folate and Vit B6; fExcludes sport drinks/bars/gels.

Table 3 shows summary data on US military DS use where questionnaires had asked about “current use” or use ≥1 time per week. Only 13 studies were included in these meta-analyses (Figure 1) because the other studies used different reporting timeframes or reported on a DS that was not included in any other study. Additional data from Bray et al. [19] was included in the table because this investigation was the only one to ask about use of any DS, multivitamins, or any vitamin or mineral supplement ≥1 time/week among Navy, Air Force, and Marine personnel. Meta-analyses indicated that the prevalence of any DS use was relatively consistent among Army studies. Among men in the four military services, use of supplements of any kind ranged from 53% to 61% of the surveyed groups; among women, use of supplements of any kind ranged from 66% to 76%. Female Army officers in training tended to have a much lower use of DSs. Reported supplement use among elite Army and Navy groups was less homogenous ranging from 56% to 90% of the surveyed groups, but was, in the main, higher than general military samples.
Table 3

Summary data on prevalence of dietary supplement use by military personnel by gender and service

Dietary supplement

Group

Studies (reference number)

Individual study prevalence, mean (95% CI)

Total sample size (n)

Summary prevalence estimate (95% CI) (%)

Homogeneity of summary prevalence estimate

   

(%)

  

(Q Statistic p-value)

Any

Army Men

Brasfield [6]

59 (56–63)

4,871

55(53–56)

0.77

Bray et al. [19]

55 (53–57)

Lieberman [26]

55 (50–60)

Lieberman et al. [8]

53 (50–56)

Navy Men

Bray et al. [19]

60 (58–62)

3,341

  

AF Men

Bray et al. [19]

60 (58–62)

3,193

  

Marine Men

Bray et al. [19]

61 (59–63)

2,767

  

Army Women

Brasfield [6]

70 (62–78)

1,844

65(60–70)

0.14

Bray et al. [19]

66 (63–69)

Lieberman [26]

70 (56–84)

Lieberman et al. [8]

57 (49–66)

Navy Women

Bray et al. [19]

71 (68–74)

1,286

  

AF Women

Bray et al. [19]

76 (74–78)

1.331

  

Marine Women

Bray et al. [19]

71 (67–75)

589

  

Army Officers in Training, Women

Klicka et al. [15]

35 (25–45)

136

36(28–44)

0.72

Arsenault et al. [35]

38 (25–51)

Navy SEALs

Schneider et al. [21]

78 (70–87)

1,479

76(65–85)

<0.01

Army SF

Bovill et al. [12]

90 (85–95)

Army Rangers

Deuster et al. [5]

82 (70–94)

Army Rangers

Johnson et al. [38]

56 (50–62)

Army Rangers

Lieberman [27]

81 (78–84)

Army SF

Lieberman [28]

65 (57–73)

Army SF

Lieberman et al. [8]

77 (57–97)

Multivitamin

Army Men

Warber et al. [16]

24 (22–26)

7,418

32(26–39)

<0.01

Brasfield [6]

33 (30–36)

Bray et al. [19]

38 (36–40)

Lieberman [26]

30 (26–34)

Lieberman [8]

37 (34–40)

Navy Men

Bray et al. [19]

46 (45–48)

3,341

  

AF Men

Bray et al. [19]

47 (45–49)

3,193

  

Marine Men

Bray et al. [19]

41 (39–43)

2,767

  

Army Women

Warber et al. [16]

35 (31–39)

1,610

40(32–48)

<0.01

Brasfield [6]

40 (31–49)

Bray et al. [19]

50 (47–53)

Lieberman [26]

28 (14–42)

Lieberman et al. 2010 [8]

41 (33–49)

Navy Women

Bray et al. [19]

55 (52–58)

1,286

  

AF Women

Bray et al. [19]

63 (60–66)

1,331

  

Marine Women

Bray et al. [19]

53 (49–57)

589

  

Navy SEALS

Schneider et al. [21]

26 (17–35)

1,147

37(25–52)

<0.01

Army SF

Bovill et al. [12]

55 (46–64)

Army Rangers

Lieberman [27]

23 (20–26)

Army SF

Lieberman [28]

32 (25–39)

Lieberman et al. [8]

64 (41–87)

Any vitamin or mineral

Army Men

Carlson et al. [14]

7 (1–13)

3,720

18(13–26)

<0.01

Bray et al. [19]

24 (22–26)

Lieberman et al. [8]

17 (15–20)

Navy Men

Bray et al. [19]

27 (25–29)

3,341

  

AF Men

Bray et al. [19]

25 (24–27)

3,193

  

Marine Men

Bray et al. [19]

24 (22–26)

2,767

  

Army Women

Bray et al. [19]

34 (31–37)

952

29(19–41)

0.01

Lieberman et al. [8]

23 (16–30)

Navy Women

Bray et al. [19]

36 (33–39)

1,286

  

AF Women

Bray et al. [19]

40 (37–43)

1,331

  

Marine Women

Bray et al. [19]

33 (29–37)

589

  

Vitamin C

Army Men

Brasfield [6]

17 (14–20)

1,609

15(12–20)

0.07

Lieberman et al. [26]

13 (10–16)

Army Women

Brasfield [6]

15 (9–21)

255

15(10–21)

0.19

Lieberman et al. 2008 [26]

13 (3–23)

Army SF

Bovill 2003 [12]

20 (13–27)

271

15(8–26)

0.04

Lieberman [28]

11 (6–16)

Vitamin E

Army Men

Brasfield [6]

10 (8–12)

514

8(5–13)

0.12

Lieberman [26]

6 (4–8)

Army Women

Brasfield [6]

7 (3–12)

164

7(4–12)

0.95

Lieberman [26]

8 (1–16)

Army SF

Bovill et al. [12]

12 (6–18)

271

9(6–15)

0.21

Lieberman [28]

7 (3–11)

Calcium

Army Men

Brasfield [6]

12 (10–14)

1,194

9(4–17)

<0.01

Lieberman [26]

6 (4–8)

Army Women

Brasfield [6]

14 (8–20)

164

14(10–20)

0.84

Lieberman[26]

15 (4–26)

Iron

Army Women

Brasfield [6]

12 (6–18)

164

12(8–18)

0.72

Lieberman [26]

10 (1–19)

Protein

Army SF

Bovill et al. [12]

24 (16–32)

271

20(13–30)

0.08

Lieberman [28]

16 (10–22)

Protein or amino acid

Navy SEALs

Schneider et al. [21]

18 (15–21)

876

21(11–36)

<0.01

Army Rangers

Lieberman [27]

12 (5–19)

Army SF

Lieberman et al. [8]

47 (23–71)

Creatine

Army Men

Brasfield [6]

16 (13–18)

1,194

9(3–27)

<0.01

Lieberman [26]

5 (3–7)

Navy SEALs

Schneider et al. [21]

32 (22–42)

1,169

20(15–25)

0.02

Army SF

Bovill et al. [12]

18 (11–25)

Army Rangers

Deuster et al.[5]

13 (2–24)

Army Rangers

Lieberman [27]

19 (16–22)

Army SF

Lieberman [28]

16 (10–22)

Sport drinks

Army Men

Lieberman [26]

20 (16–24)

1,303

22(19–25)

0.22

Lieberman et al. [8]

23 (20–26)

Army Women

Lieberman [26]

28 (14–42)

171

25(19–32)

0.24

Lieberman et al. [8]

24 (17–31)

Navy SEALs

Schneider et al. [21]

19 (11–27)

1,147

39(26–55)

<0.01

Army SF

Bovill et al. [12]

71 (63–79)

Army Rangers

Lieberman [27]

41 (38–44)

Army SF

Lieberman [28]

36 (28–44)

Army SF

Lieberman et al. [8]

32 (10–54)

Sport bars

Army Men

Warber et al. [16]

8 (7–9)

3,890

7(5–9)

0.03

Lieberman [26]

5 (3–7)

Lieberman et al. [8]

6 (4–8)

Army Women

Warber et al. [16]

3 (2–5)

625

3(2–5)

0.65

Lieberman et al. [8]

4 (1–7)

Navy SEALs

Schneider et al. [21]

40 (30–50)

1,147

19(6–46)

<0.01

Army SF

Bovill et al. [12]

52 (43–61)

Army Rangers

Lieberman [27]

6 (4–8)

Army SF

Lieberman [28]

15 (9–21)

Army SF

Lieberman et al. [8]

7 (1–14)

Abbreviations: AF = Air Force; SEAL = Sea, Air, Land (US Navy special operations personnel); SF = Special Forces; CI = confidence interval.

Table 3 shows prevalence data on MVM use by military personnel. Army studies demonstrated a lack of homogeneity for both men and women. Among men in the four military services, MVM use ranged from 24% to 47% with Army men less likely to consume multivitamins than men in the other services. Among women, MVM use ranged from 28% to 63% in the four services, again with Army women less likely to consume multivitamins than women in other services. Reported MVM use among elite military groups appeared to be similar to that of Army men but the prevalence values lacked homogeneity and ranged from 26% to 64%.

Table 3 shows that studies on the use prevalence of any vitamin or mineral supplement by Army men and women lacked homogeneity. Nonetheless, data suggested women used vitamin and mineral supplements more often than men, regardless of service. Among all four services, prevalence of use of any vitamin or mineral supplement among men ranged from 7% to 27% while for women this range was 23% to 40%.

Table 3 shows other DSs that had multiple studies and fit the table criteria (current use or use ≥ 1 times/week). These included Vitamin C, Vitamin E, calcium, iron, proteins, protein or amino acids, creatine, sport drinks, and sport bars. Multiple studies (i.e., ≥2) were limited to Army men, Army women, and some elite military groups. The prevalence of Vitamin C supplementation was 15% for Army men, Army women, and Special Forces soldiers, although the latter estimate lacked homogeneity. The prevalence of Vitamin E supplementation was similar among Army men and the Special Forces soldiers and slightly higher than that of Army women. Calcium supplementation was slightly more prevalent among Army women compared to Army men, although the two available male studies were not homogeneous. Creatine use appeared more prevalent among samples of elite Army men compared to general male Army samples, although prevalence values differed considerably. When the Navy SEAL study [21] was eliminated from the analysis of creatine prevalence, studies on Rangers and Special Forces soldiers had a SPE = 19% and S95% CI = 16-21 (p = 0.88 for homogeneity). Use prevalence of sport drinks was similar among the general samples of Army men and women. Meta-analysis suggested that elite military group use of sport drinks was higher than in general Army samples but studies of elite groups lacked homogeneity, with individual study prevalences ranging from 19% to 71%. The prevalence of sport bar usage was low among samples of Army men and even lower among Army women. Sport bar usage appeared much higher in some samples of elite military groups but there was a lack of homogeneity with prevalences ranging from 6% to 52%.

The curve fitting procedures did not indicate any significant temporal trends among studies. This can be appreciated by examining the data presented by year in Table 3.

Discussion

This review demonstrates that the prevalence of DS use was high among members of the military services. Available data indicated that the self-reported prevalence of DS current use or use ≥1 time/week was slightly lower among Army men (55%) than among men in the other 3 military services (~60%). Female service members reported a higher prevalence of DS use than male service members but again, Army women reported a slightly lower use of DSs of any kind (66%) compared to women in the other 3 services (71 to 76%). The pattern of MVM use was similar to that of the overall use prevalence. That is, Army men and women report MVM use prevalences lower than the other services but women in all services report use prevalences higher than their male counterparts in the same service. Prevalence estimates varied in groups of elite service members (Army Rangers, Army Special Forces, and Navy SEALs) but generally, the use prevalence of supplements of any kind was higher (56% to 90%) than that of other service members. Interestingly, male and female Army officers in training tended to have a lower prevalence of DS use, possibly related to the fact that they were eating in military dining facilities and had busy training schedules.

MVM appeared to be the most commonly used DS among the general population of military personnel with 24% to 47% of male and 28% to 63% of female service members using these supplements. This is in consonance with data on athletes [49, 50] and the general US population [5156] where MVM are also the most commonly consumed DS. Table 4 shows summary data from the National Health Interview Surveys (NHIS) [54, 55, 57] and the National Health and Nutrition Surveys (NHANES) [5861], both of which are nationally representative samples of the general US population. It was difficult to directly compare military MVM prevalence data to that of these national surveys because the military and civilian studies differed in terms of the reporting timeframe, methods used to collect the data, and the years when the data were collected. Despite these issues, it was possible to make some general observations. The NHANES and NHIS surveys indicated that women were more likely to use DSs than men, in agreement with the military data. Both NHANES and NHIS surveys observed a temporal trend indicating that DS use increased over time, although the most recent NHANES data suggested a leveling off [60, 61]. No such temporal trends could be discerned in the military data, possibly because of the shorter time over which the studies were conducted and lack of questionnaire standardization across studies. Use of MVM appeared to be higher in the military compared to these civilian samples.
Table 4

Summary data on DS Use in United States national surveys

Survey

Study

Survey year(s)

N

Reporting timeframe

Prevalence (%)

     

Any VM

Multivitamin

Vitamin C

Vitamin E

Calcium

     

Men

Women

Men

Women

Men

Women

Men

Women

Men

Women

National Health Interview Survey (NHIS)

Subar & Block [57]

1987

9,160 ♂, 12,920 ♀

Daily Use

19

27

15

20

7

8

4

5

3

10

Slesinski et al. [54]

1992

5,120 ♂, 6,885 ♀

Daily Use

20

27

17

22

7

8

4

5

2

8

Millen et al. [55]

2000

34,085 ♂ & ♀

Daily Use

29

39

24

33

10

12

10

13

4

17

National Health and Nutrition Survey (NHANES)

Koplan et al. [58]

1976-1980

5,915 ♂, 6,588 ♀

Use ≥ 1 time/wk

30

40

ND

ND

ND

ND

ND

ND

ND

ND

Balluz et al. [59]

1988-1994

33,905 ♂ & ♀

Use in Last Month

35

44

ND

ND

ND

ND

ND

ND

ND

ND

Radimer et al. [60]

1999-2000

2,260 ♂, 2,602 ♀

Use in Last month

46

57

32

38

12

13

12

14

4

16

 

Kennedy et al. [61]

2007-2008

3,364 ♂ & ♀

Use in Last Month

42

54

ND

ND

ND

ND

ND

ND

ND

ND

Abbreviations: VM = vitamin and/or mineral; ♂ = men; ♀ = women; ND = no data; wk = week.

Among military personnel, the most common rationale for taking MVMs was to promote general health with 76% of individuals reporting this reason in one study [8]. Most MVM supplements contain at least 10 vitamins and/or minerals with a great range of dosages [62]. Systematic and narrative reviews on the effects of MVM supplements on health have indicated that there is little convincing evidence that these DSs influence the incidence of cataracts, cardiovascular disease, diabetes [6365], or cancers of the prostate, lungs, or breast [64, 6668]. On the other hand some studies suggest MVM supplements may improve cognitive functioning [69, 70], reduce infection risk in older individuals [71], reduce colon cancer risk [72] and, when used for primary prevention, reduce the risk of all-cause mortality [73], although results are not consistent [65]. The determination of the safety of vitamins and minerals differs from that of other substances like toxins or other chemicals because a certain level of vitamins and minerals are needed for good health but above or below that level, an adverse effect may occur. Thus, there is a “U-shaped” relationship between the dosage and the likelihood of adverse effects and dose–response curve will differ for different DSs [74].

Use prevalence of individual vitamins and minerals were less often reported in military studies but a few studies of Army personnel had examined Vitamin C, Vitamin E, calcium, and iron [6, 12, 26]. Generally, the use prevalence of Vitamin C was similar among Army men, women, and Special Forces Soldiers (15%). Vitamin E use prevalence was about the same among Army men, Army women, and elite groups (7-12%). Women appeared more likely to supplement with calcium (14%) compared to Army men (9%). Table 4 provides data on Vitamin C, Vitamin E, and calcium supplementation from the NHIS. Again, comparisons with the military data are limited for reasons cited above. Nonetheless, the NHIS and NHANES general trends were similar to the military data in that men and women were about equally likely to supplement with Vitamins C and E and women were more likely to use calcium.

Vitamin C and E are antioxidant vitamins and they have been studied in disease states like cancer, cardiovascular disease, and macular degeneration where oxidative stress mechanisms produce cellular damage [75, 76]. In systematic reviews, Vitamin C and E supplementation either alone or in combination with other substances did not reduce the incidence of cardiovascular disease [64, 75, 77] or prostate cancer [66]. Supplemental Vitamin C may have modestly reduced the risk of breast cancer but Vitamin E did not [78]. Vitamin C and E from any source (diet or supplements) appeared to reduce the incidence of endometrial cancer [79]. Calcium supplementation with Vitamin D reduced stress fracture risk in basic training [80].

The prevalence of herbal supplement use by military personnel was small, usually 5% or less of the groups surveyed [6, 17, 23, 29, 33, 39, 45], although ginseng use was 14% in one Army study [6]. The nationally representative NHIS data from 2007 indicated that 17%, 12%, 12%, and 11% of the surveyed group had used Echinacea, garlic supplements, ginseng, and ginkgo biloba, respectively, in the last 30 days [81]. In athletic groups, 2% to 10% reported current use of ginseng and 4 to 7% reported current use of Echinacea [50, 82, 83].

Sport drinks are a general category of beverages that contain water, carbohydrates, minerals, and electrolytes, and may contain small amounts of vitamins. They are designed to be used during and after sport and exercise activities for rehydration, replacement of electrolytes lost during sweating, and energy (i.e., supply carbohydrates during activity or replenish muscle glycogen post-activity) [84, 85]. Sport drinks appeared to be a very common nutritional supplement used by elite military groups, although the use prevalence range was wide (19% to 71%) in the various investigations. Sport drink use prevalence was also high among the general male and female military population (~23%) but this did not exceed the use prevalence for MVMs in these groups. The relatively high use of sport drinks among elite military groups is in consonance with studies of elite athletes showing that the use of sport drinks exceeds that of multivitamins [8688]. Data from the NHIS indicated that 22% reported the use of sport or energy drinks ≥1 time/week but that survey did not provide data on the two beverages separately [89]. Data from NHANES indicated an almost tripling in the use of sport and energy drinks (combined) among adolescents and young adults (12 to 34 years of age) over the 1999 to 2008 period [90].

Creatine was a DS with relatively high use prevalence among elite service members (20%) and among Army men (14%), although the two studies on Army men had widely varying prevalence values [6, 26]. The 2007 NHIS survey reported a 3% use prevalence in the general US population [81]. Studies on athletes have found that creatine use prevalence is highly variable and dependent on the sport. Athletes in strength and power sports (e.g., weightlifting, football, track and field) used creatine to a greater extent than those involved in endurance activities [9194]. Research has generally shown that creatine supplementation can improve strength and performance in short-term, high intensity physical activities [9598]. In combination with resistance training, creatine increased maximal muscle strength to a greater extent than resistance training alone [99].

In elite military groups, the use prevalence for protein supplements was about 20% but varied widely, between 12% and 47% [8, 12, 21, 27]. The only study to report on the protein supplementation in the general male army population found a use prevalence of 13% [26], while another study reporting on combined proteins and amino acids found a use prevalence of 20% [8]. One national survey (Health and Diet Survey conducted by the US Food and Drug Administration) reported that about 1% of the total sample had used amino acid supplements in the last year [56]. The Recommended Daily Allowance for protein is 0.8 gmkg body weight −1day−1[100]. However, summaries of studies indicated that the daily average intake of protein among strength-trained athletes was 2.1 gmkg−1day−1[101] while that among endurance athletes was 1.8 ± 0.4 gmkg−1day−1 for men and 1.2 ± 0.03 gmkg−1day−1 for women [102]. A recent consensus statement on the efficacy of protein supplementation in military personnel recommended 1.5 to 2.0 gmkg−1day−1 for service members involved in substantially increased metabolic demand and 1.2 to 1.5 gmkg−1day−1 for older service members [103]. A meta-analysis of 22 studies suggested that protein supplementation (>1.2 gmkg−1day−1) with resistance training resulted in modestly greater gains in fat-free mass (0.7 kg, 95% CI = 0.5-0.9 kg) and strength when compared to training without protein supplementation [104].

Three studies reported on energy drink consumption among soldiers [42] and among soldiers and marines deployed in Afghanistan [9, 44]. Prevalence of energy drink usage was 25% among female soldiers [42] and 41% to 45% among male soldiers and marines [9, 42, 44]. There are about 500 brands of energy drinks available worldwide and about 200 are available in the US [105, 106]. Literature reviews examining commonly available energy drinks found that virtually all contained caffeine, taurine, and B-Vitamins, while other common ingredients contained in most included guarana, ginseng, sugars, and carnitine. Other ingredients found in some energy drinks include ginkgo biloba, milk thistle, branched-chain amino acids, choline, chromium, green tea, hornet saliva, inositol, yerba mate, triglycerides, proline, pyruvate, royal jelly, schizandra, aloe vera, bee pollen, borage oil, and stabilized oxygen. Reviews have generally concluded that except for some relatively weak evidence for glucose and guarana, there was little evidence for a positive effect on cognitive or physical performance for any of those ingredients other than caffeine [106108]. Caffeine has been shown to increase performance during long-term exercise, shorter-term high intensity exercise (60–180 sec), and high intensity intermittent exercise, but effects on muscle strength are equivocal. Caffeine may produce ergogenic effects through a variety of mechanisms that include increasing fat oxidation (thus sparing glucose and muscle glycogen during long-term exercise), central nervous system stimulation, a direct action on muscles, and/or a competitive inhibition with adenosine. The adenosine mechanism involves caffeine occupying adenosine sites in the central nervous system which increase catecholamine release and lipolysis. Tolerance to caffeine has often been reported and may be associated with the up-regulation of adenosine receptors [109112].

Of interest were the studies on Marine Corps and Air Force trainees that asked about lifetime prevalence of DS use [36, 39]. About 82% of the participants in these two studies were men. The lifetime prevalence of any DS use was 41% [36] and 50% [39]. These prevalences were lower than those reported by Bray et al. [19] for longer-serving Marine and AF personnel (~60%). These data suggest that a number of service members have used DSs before entering the Air Force or Marine Corps but that prevalence becomes higher once individuals spend time in these services. Military service may increase DS use because of the demands of the occupations and the belief that DSs will improve health and increase performance on occupational tasks.

In the nine investigations that examined the prevalence of DS use in elite military units [5, 8, 12, 21, 22, 27, 28, 38],[45], all but two [22, 38] reported a higher use of DSs (any use) among these elite service members compared to non-elite male military samples. This is similar to results found for elite athletes where athletes participating at higher levels of competition (Olympic, national, or international level) were more likely to use DSs than those competing as recreational athletes [49]. Elite athletes and elite service members may be similar in that they seek to gain additional physical advantages from the use of DSs.

Five studies provided information on the reasons that service members used DSs [6, 8, 9, 19, 33]. In four of the five, “general health” was listed as the reason with the highest frequency with performance enhancement listed as second most common (first in Cassler et al. study [9] of deployed marines). Thus, service members reported using DSs for the same reason as civilians, [10, 11] but a second very common reason was performance enhancement which is seldom mentioned in civilian investigations. In this sense, service members are like athletes who also report performance enhancement as a high frequency reason for DS use [113115]. Like athletes, service members’ occupational tasks require a high level of physical performance; they are unlike most athletes in that their activity may be performed in hostile locations and under adverse and austere environmental conditions.

Future studies on the prevalence of DS use should consider five major issues. First, the definition of DSs should be clearly stated on the questionnaire instructions. The legal definition provided by The Dietary Supplement Health and Education Act of 1994 [2] can serve as a standard. Second, studies should be specific about the types of DSs used by study participants. Reporting in general categories like “antioxidant”, “energy”, “herbal”, “bodybuilding”, and the like does not provide the specificity needed for comparisons across studies and the identification of specific DS use. Third, the reporting timeframe should be specific and include several periods. The most useful reporting timeframes appear to be daily, 2–6 times/week, 1 time/week and 1 time/month. Fourth, the response rate of survey should be specified and, if possible, characteristics of respondents and non-respondents should be described so that possible bias can be assessed. Finally, studies are needed that use the same experimental methods to compare DS use across all the military services over time.

There were limitations to this review. Studies differed on the reporting timeframe, questionnaire construction, and supplement definitions which made it difficult to directly compare results across all studies. In the meta-analysis, an attempt was made to control for the reporting timeframe by only examining studies asking service members about current supplement use or use ≥1 day/week. We only examined specific DSs and did not include DSs that were included in broad categories (e.g., antioxidant, ergogenics, bodybuilding). Thus, we may have underestimated DSs in some categories, although most unique studies (n = 24, 72%) did report use of “any” DS. Some questionnaires involved “checklists” of specific DSs that may have elicited better subject recall than open-ended questions asking subjects to list the DSs that they used. In most studies, the actual questionnaire structure and/or questionnaire items were not specified and the only apparent fact was that the questionnaire did or did not focus on DSs. It is possible that some service members may have been involved in one or more surveys but the number of these individuals would likely have been very small. Some values had to be estimated from graphic presentations which could have resulted in small errors. The analyses of temporal trends depended on the publication year which was likely not the year that the data were collected. Other problems common to self-reporting included the accuracy of subject recall and the possible reluctance of some individuals to report specific DSs that they used.

Conclusion

In conclusion, this review provided a comprehensive overview of military DS use by gender and type of military service. It demonstrated that Army personnel tended to use DSs and MVM less than other service members but that regardless of service, the use of any DS and MVMs are higher among women than men. Military personnel’s use of herbal supplements is small, <5% in most investigations. Elite military men appeared to use DSs and sport drinks more than other service members.

Authors’ information

The views, opinions, and/or findings contained in this report are those of the authors and should not be construed as official Department of the Army position, policy, or decision, unless so designated by other official documentation. Approved for public release; distribution is unlimited.

Abbreviations

US: 

United States

DS: 

Dietary supplement

MVM: 

Multivitamin/multimineral

SPE: 

Summary prevalence estimate

S95% CI: 

Summary 95% confidence Interval

SEAL: 

Sea, air, land (Navy Special Operations Personnel)

DTIC: 

Defense technical information center

NHANES: 

National Health and Nutrition Survey

NHIS: 

National Health Interview Survey

95% CI: 

95% confidence interval.

Declarations

Acknowledgements

We would like to thank Claudia Coleman and Dr Wayne Askew who assisted us in obtaining references. This research was supported in part by an appointment to the Knowledge Preservation Program at the US Army Research Institute of Environmental Medicine (USARIEM) and the Army Institute of Public Health (AIPH) administered by the Oak Ridge Institute for Science and Education through an interagency agreement between the U.S. Department of Energy and USARIEM. Funding was also provided by the Department of Defense Center for Dietary Supplement Research and the Medical Research and Development Command.

Authors’ Affiliations

(1)
US Army Research Institute of Environmental Medicine
(2)
US Army Institute of Public Health, Aberdeen Proving Ground
(3)
Serenity Hill Nutrition
(4)
Oak Ridge Institute for Science and Education
(5)
Research Physiologist, ORISE Knowledge Preservation Fellow, USARIEM

References

  1. Strengthening knowledge and understanding of dietary supplements. [http://ods.od.nih.gov/About/DSHEA_Wording.aspx], accessed 4 February 2013
  2. Dietary Supplement Health and Education Act of 1994. [http://www.fda.gov/RegulatoryInformation/Legislation/FederalFoodDrugandCosmeticActFDCAct/SignificantAmendmentstotheFDCAct/ucm148003.htm], accessed 11 March 2013
  3. Saldanha LG: The dietary supplement marketplace. Constantly evolving. Nutr Today. 2007, 42 (2): 52-54. 10.1097/01.NT.0000267126.88640.3d.Google Scholar
  4. Considering a post-DSHEA World. Nutr Bus J. 2012, 17 (5/6): 1, 3-9.
  5. Deuster PA, Sridhar A, Becker WJ, Coll R, O’Brien KK, Bathalon G: Health assessment of U.S. Army Rangers. Mil Med. 2003, 168 (1): 57-62.PubMedGoogle Scholar
  6. Brasfield K: Dietary supplement intake in the active duty enlisted population. US Army Med Dep J. 2004, 44-56.Google Scholar
  7. Boos CJ, Wheble GAC, Campbell MJ, Tabner KC, Woods DR: Self-administration of exercise and dietary supplements in deployed British military personnel during operation TELIC 13. J R Army Med Corps. 2010, 156 (1): 32-36. 10.1136/jramc-156-01-07.PubMedGoogle Scholar
  8. Lieberman HR, Stavinoha TB, McGraw SM, White A, Hadden LS, Marriott BP: Use of dietary supplements among active-duty US Army soldiers. Am J Clin Nutr. 2010, 92 (4): 985-995. 10.3945/ajcn.2010.29274.PubMedGoogle Scholar
  9. Cassler NM, Sams R, Cripe PA, McGlynn AF, Perry AB, Banks BA: Patterns and perceptions of supplement use by U.S. Marines deployed to Afghanistan. Mil Med. 2013, 178 (6): 659-664. 10.7205/MILMED-D-12-00440.PubMedGoogle Scholar
  10. Bailey RL, Gahche JJ, Miller PE, Thomas PR, Dwyer JT: Why US adults use dietary supplements. JAMA Int Med. 2013, 173 (3): 355-361.Google Scholar
  11. Dickinson A, Bonci L, Boyon N, Franco JC: Dietitians use and recommend dietary supplements: report of a survey. Nutr J. 2012, 11: 14-10.1186/1475-2891-11-14.PubMedPubMed CentralGoogle Scholar
  12. Bovill ME, Tharion WJ, Lieberman HR: Nutrition knowledge and supplement use among elite U.S. Army soldiers. Mil Med. 2003, 168 (12): 997-1000.PubMedGoogle Scholar
  13. Loney PL, Chambers LW, Bennett KJ, Roberts JG, Stratford PW: Critical appraisal of health research literature: prevalence or incidence of a health problem. Chronic Dis Can. 2000, 19 (4): 170-176.Google Scholar
  14. Carlson DE, Dugan T, Buchbinder J, Allegetto J, Schnakenberg DD: Nutritional Assessment of the Ft Riley Non-Commissioned Officer Academy Dining Facility. 1987, Natick MA: US Army Research Institute of Environmental Medicine Technical Report No. T14-87Google Scholar
  15. Klicka MV, Sherman DE, King N, Friedl KE, Askew EW: Nutritional Assessment of Cadets at the U.S. Military Academy. Part 2. Assessment of Nutritional Intake. 1994, Natick MA: US Army Research Institute of Environmental Medicine Technical Report No. T94-1Google Scholar
  16. Warber J, McGraw S, Kramer FM, Lesher L, Johnson W, Cline A: The Army Food and Nutrition Survey. 1999, Natick MA: US Army Research Institute of Environmental Medicine Technical Report No. XX-99Google Scholar
  17. Shanks K: Prevalence of Herbal Therapy use in Active Duty Air Force Women. 2001, Bethesda MD: Uniformed Services University of the Health Sciences Technical Report No. C101-88Google Scholar
  18. Castillo EM, Hurtado SL, Shaffer RA, Rock CL, Brodine SK: Dietary Supplement use in a Physically Active Population. 2004, San Diego CA: Naval Health Research Center Technical ReportGoogle Scholar
  19. Bray RM, Hourani LL, Olmsted KLR, Witt M, Brown JM, Pemberton MR, Marsden ME, Marriott B, Scheffler S, Vandermass-Peeler R, Weimer B, Calvin S, Bradshaw M, Close K, Hayden D: 2005 Department of Defense Survey of Health Related Behaviors Among Active Duty Personnel Research Triangle. 2006, Park NC: Research Triangle Institute Technical Report No. RTI/7841/106-FRGoogle Scholar
  20. Wells TS, Webb TS: Modifiable Characteristics Associated With the Training Success Among US Air Force Tactical Control Party Candidates. 2010, Wright-Patterson Air Force Base OH: Air Force Research Laboratory Technical ReportGoogle Scholar
  21. Schneider K, Hervig L, Ensign WY, Prusaczyk WK, Goforth HW: Use of supplements by U.S. Navy seals. Med Sci Sports Exerc. 1998, 30 (5): 60-Google Scholar
  22. McGraw SM, Therion WJ, Lieberman HR: Use of nutritional supplements by U.S. Army Rangers. FASEB J. 2000, 14 (4): A742-Google Scholar
  23. Corum S: Findings of Recent Surveys on Dietary Supplements Use by Military Personnel and the General Population (Appendix C). Use of Dietary Supplements by Military Personnel. Edited by: Greenwood MRC, Oria M. 2008, Washington DC: National Academy Press, 384-385.Google Scholar
  24. French A: Findings of Recent Surveys on Dietary Supplements Use by Military Personnel and the General Population (Appendix C). Use of Dietary Supplements by Military Personnel. Edited by: Greenwood MRC, Oria M. 2008, Washington DC: National Academy Press, 386-387.Google Scholar
  25. Marroitt BM: Findings of Recent Surveys on Dietary Supplements Use by Military Personnel and the General Population (Appendix C). Use of Dietary Supplements by Military Personnel. Edited by: Greenwood MRC, Oria M. 2008, Washington DC: National Academy Press, 404-405.Google Scholar
  26. Lieberman H: Findings of Recent Surveys on Dietary Supplements Use by Military Personnel and the General Population (Appendix C). Use of Dietary Supplements by Military Personnel. Edited by: Greenwood MRC, Oria M. 2008, Washington DC: National Academy Press, 398-399.Google Scholar
  27. Lieberman H: Findings of Recent Surveys on Dietary Supplements Use by Military Personnel and the General Population (Appendix C) Army Rangers. Use of Dietary Supplements by Military Personnel. Edited by: Greenwood MRC, Oria M. 2008, Washington DC: National Academy Press, 400-401.Google Scholar
  28. Lieberman H: Findings of Recent Surveys on Dietary Supplements Use by Military Personnel and the General Population (Appendix C), Special Forces. Use of Dietary Supplements by Military Personne. Edited by: Greenwood MRC, Oria M. 2008, Washington DC: National Academy Press, 400-401.Google Scholar
  29. Lieberman H: Findings of Recent Surveys on Dietary Supplements Use by Military Personnel and the General Population (Appendix C), Army War College. Use of Dietary Supplements by Military Personnel. Edited by: Greenwood MRC, Oria M. 2008, Washington DC: National Academy Press, 402-403.Google Scholar
  30. Johnson AE: Findings of Recent Surveys on Dietary Supplements Use by Military Personnel and the General Population (Appendix C). Use of Dietary Supplements by Military Personnel. Edited by: Greenwood MRC, Oria M. 2008, Washington DC: National Academy Press, 414-415.Google Scholar
  31. Thomasos CJ: Findings of Recent Surveys on Dietary Supplements Use by Military Personnel and the General Population (Appendix C). Use of Dietary Supplements by Military Personnel. Edited by: Greenwood MRC, Oria M. 2008, Washington DC: National Academy Press, 406-407.Google Scholar
  32. Klicka MV, King N, Lavin PT, Askew EW: Assessment of dietary intake of cadets at the US Military Academy at West Point. J Am Coll Nutr. 1996, 15 (3): 273-282. 10.1080/07315724.1996.10718598.PubMedGoogle Scholar
  33. Kennedy J, Arsenault J: Dietary supplement use in U.S. Army Special Forces Operations Candidates. Mil Med. 1999, 164 (7): 495-501.PubMedGoogle Scholar
  34. Sheppard HL, Raichada SM, Kouri KM, Stenson-Bar-Maor L, Branch JD: Use of creatine and other supplements by members of civilian and military health clubs: a cross-sectional survey. Int J Sport Nutr Exerc Metab. 2000, 10: 245-259.PubMedGoogle Scholar
  35. Arsenault JE, Cline AD: Nutrition intakes and characteristics of normal weight, female personnel consuming foods reduced in fat or energy content. Appetite. 2000, 34: 227-233. 10.1006/appe.1999.0315.PubMedGoogle Scholar
  36. Stevens MB, Olsen C: Ergogenic supplements and health risk behaviors. J Fam Pract. 2001, 50 (8): 696-699.Google Scholar
  37. Smith TC, Ryan MAK, Smith D, Reed RJ, Riddle JR, Gumbs GR, Gray GC: Complementary and alternative medicine use among US Navy and Marine Corps personnel. BMC Complement Altern Med. 2007, 7: 16-10.1186/1472-6882-7-16.PubMedPubMed CentralGoogle Scholar
  38. Johnson AE, Haley CA, Ward JA: Hazards of dietary supplement use. J Spec Oper Med. 2007, 7 (1): 30-38.Google Scholar
  39. Young CR, Stevens MB: Sports and nutritional supplement use in USMC recruits: a pilot study. Mil Med. 2009, 174 (2): 158-161. 10.7205/MILMED-D-00-4708.PubMedGoogle Scholar
  40. Boos CJ, Simms P, Morris FR, Fertout M: The use of exercise and dietary supplements among British soldiers in Afghanistan. J R Army Med Corps. 2011, 157 (3): 229-232. 10.1136/jramc-157-03-08.PubMedGoogle Scholar
  41. Carvey CE, Farina EK, Lieberman HR: Confidence in the efficacy and safety of dietary supplements among United States active duty Army personnel. BMC Complement Altern Med. 2012, 12: 182-10.1186/1472-6882-12-182.PubMedPubMed CentralGoogle Scholar
  42. Lieberman HR, Stavinoha T, McGraw S, White A, Hadden L, Marriott BP: Caffeine use among active duty US Army soldiers. J Acad Nutr Diet. 2012, 112 (6): 902-912. 10.1016/j.jand.2012.02.001.PubMedGoogle Scholar
  43. Jacobson IG, Horton JL, Smith B, Wells TS, Boyko EJ, Lieberman HR, Ryan MAK, Smith TC: Bodybuilding, energy, and weight loss supplements are associated with deployment and physical activity in U.S. military personnel. Ann Epidemiol. 2012, 22 (5): 318-330. 10.1016/j.annepidem.2012.02.017.PubMedGoogle Scholar
  44. Toblin RL, Clarke-Walper K, Kok BC, Sipos ML, Thomas JL: Energy drink consumption and its association with sleep problems among U.S. service members on a combat deployment--Afghanistan. MMWR. 2012, 61 (44): 895-898.Google Scholar
  45. Kjertakov M, Hristovski R, Racaj M: The use of dietary supplement among soldiers from the Macedonian Special Operations Regiment. J Spec Oper Med. 2013, 13 (1): 19-24.PubMedGoogle Scholar
  46. Hill TM, Nelson RA, Consolazio CF, Canham JE: Nutrient Intake of the Repatriated United States Army, Navy and Marine Corps Prisoners-of-war of the Vietnam War. 1978, Presidio of San Francisco: Letterman Army Institute of Research Technical Report No. 61Google Scholar
  47. Jaghab S: Findings of Recent Surveys on Dietary Supplements Use by Military Personnel and the General Population (Appendix C). Use of Dietary Supplements by Military Personnel. Edited by: Greenwood MRC, Oria M. 2008, Washington DC: National Academy Press, 394-395.Google Scholar
  48. Institutes of Medicine: Use of Dietary Supplements by Military Personnel. 2008, Washington DC: Institute of MedicineGoogle Scholar
  49. Sobal J, Marquart LF: Vitamin/mineral supplement use among athletes: a review of the literature. Int J Sports Nutr. 1994, 4: 320-334.Google Scholar
  50. Huang SH, Johnson K, Pipe AL: The use of dietary supplements and medications by Canadian athletes at the Atlanta and Sydney Olympic Games. Clin J Sport Med. 2006, 16 (1): 27-33. 10.1097/01.jsm.0000194766.35443.9c.PubMedGoogle Scholar
  51. Rhee KS, Stubbs AC: Health food users in two Texas cities. J Am Diet Assoc. 1976, 68: 542-545.PubMedGoogle Scholar
  52. Schutz HG, Read M, Bendel R, Bhalla VS, Harrill I, Monagle JE, Sheehan ET, Standal BR: Food supplement usage in seven Western states. Am J Clin Nutr. 1982, 36: 897-901.PubMedGoogle Scholar
  53. Block G, Cox C, Madans J, Schreiber GB, Melia N: Vitamin supplement use, by demographic characteristics. Am J Epidemiol. 1988, 127 (4): 297-309.PubMedGoogle Scholar
  54. Slesinski MJ, Subar AF, Kahle LL: Trends in the use of vitamin and mineral supplements in the United States: the 1987 and 1992 National Health Interview Surveys. J Am Diet Assoc. 1995, 95 (8): 921-923. 10.1016/S0002-8223(95)00255-3.PubMedGoogle Scholar
  55. Millen AE, Dodd KW, Subar AF: Use of vitamin, mineral nonvitamin and nonmineral supplements in the United States: the, 1992 and 2000 National Health Interview Survey results. J Am Diet Assoc. 1987, 2004 (104): 942-950.Google Scholar
  56. Timbo BB, Ross MP, McCarthy PV, Lin CTJ: Dietary supplements in a national survey: prevalence of use and reports of adverse events. J Am Diet Assoc. 2006, 106: 1966-1974. 10.1016/j.jada.2006.09.002.PubMedGoogle Scholar
  57. Subar AF, Block G: Use of vitamin and mineral supplements: demographics and amount of nutrients consumed. Am J Epidemiol. 1990, 132 (6): 1091-1101.PubMedGoogle Scholar
  58. Koplan JP, Annest JL, Layde PM, Rubin GL: Nutrient intake and supplementation in the United States (NHANES II). Am J Public Health. 1986, 76 (3): 287-289. 10.2105/AJPH.76.3.287.PubMedPubMed CentralGoogle Scholar
  59. Balluz LS, Kieszak SM, Philen RM, Mulinare J: Vitamin and mineral supplement use in the United States. Arch Fam Med. 2000, 9: 258-262. 10.1001/archfami.9.3.258.PubMedGoogle Scholar
  60. Radimer K, Bindewald B, Hughes J, Ervin B, Swanson C, Picciano MF: Dietary supplement use by US adults: data from the National Health and Nutrition Examination Survey,1999–2000. Am J Epidemiol. 2004, 160 (4): 339-349. 10.1093/aje/kwh207.PubMedGoogle Scholar
  61. Kennedy ET, Luo H, Houser RF: Dietary supplement use pattern of US adult population in the,2007–2008 National Health and Nutrition Survey (NHANES). Ecol Food Nutr. 2013, 52 (76): 84-Google Scholar
  62. Huang HY, Caballero B, Chang S, Alberg AJ, Semba RD, Schneyer C, Wilson RF, Cheng TY, Prokopowicz G, Barnes GJ, Vassy J, Bass EB: Multivitamin/Multimineral Supplements and Prevention of Chronic Diseases. 2007, Rockville MD: Agency for Healthcare Research and Quality (US) Technical Report No. 139Google Scholar
  63. Huang HY, Caballero B, Chang S, Alberg AJ, Semba RD, Schneyer C, Wilson RF, Cheng TY, Vassy J, Prokopowicz G, Barnes GJ, Bass EB: The efficacy and safety of multivitamin and mineral supplement use to prevent cancer and chronic disease in adults: a systematic review for a National Institute of Health State-of-the-Science Conference. Ann Int Med. 2006, 145: 372-385. 10.7326/0003-4819-145-5-200609050-00135.PubMedGoogle Scholar
  64. Fortmann SP, Burda BU, Senger CA, Linn JS, Whitlock EP: Vitamin and mineral supplements in the primary prevention of cardiovascular disease and cancer: an updated systematic evidence review for the US Preventive Services Task Force. Ann Int Med. 2013, 159 (12): 824-834.PubMedGoogle Scholar
  65. Sesso HD, Christen WG, Bubes V, Smith JP, MacFadyen J, Schvartz M, Manson JE, Glynn RJ, Buring JE, Gaziano JM: Multivitamins in the prevention of cardiovascular disease in men. The Physicians’ Health Study II Randomized Controlled Trial. JAMA. 2012, 308 (17): 1751-1760. 10.1001/jama.2012.14805.PubMedPubMed CentralGoogle Scholar
  66. Stratton J, Godwin M: The effect of supplemental vitamins and minerals on the development of prostate cancer: a systematic review and meta-analysis. Fam Pract. 2011, 28: 243-252. 10.1093/fampra/cmq115.PubMedGoogle Scholar
  67. Slatore CG, Littman AJ, Au DH, Satia JA, White E: Long-term use of supplemental multivitamins, Vitamin C, Vitamin E, and folate does not reduce the risk of lung cancer. Am J Respir Crit Care Med. 2007, 177: 524-530.PubMedPubMed CentralGoogle Scholar
  68. Cho E, Hunter DJ, Spiegelman D, Albanes D, Beeson WL, VandenBrandt PA, Colditz GA, Feskanich D, Folsom AR, Fraser GE, Freudenheim JL, Giovannucci E, Goldbohm RA, Graham S, Miller AB, Rohan TE, Sellers TA, Virtamo J, Willett WC, Smith-Warner SA: Intakes of Vitamins A, C, and E and folate and multivitamins and lung cancer: a pooled analysis of 8 prospective studies. Int J Cancer. 2006, 118: 970-978. 10.1002/ijc.21441.PubMedGoogle Scholar
  69. Kennedy DO, Haskell CF: Vitamins and cognition. What is the evidence?. Drugs. 2011, 71 (15): 1957-1971. 10.2165/11594130-000000000-00000.PubMedGoogle Scholar
  70. Grima NA, Pase MP, MacPherson H, Pipingas A: The effects of multivitamins on cognitive performance: a systematic review and meta-analysis. J Alzheimer’s Dis. 2012, 29: 561-569.Google Scholar
  71. Stephens AI, Avenell A: A systematic review of multivitamin and multimineral supplementation for infection. J Hum Nutr Dietet. 2006, 19: 179-190. 10.1111/j.1365-277X.2006.00694.x.Google Scholar
  72. Park Y, Spiegelman D, Hunter DJ, Albanes D, Bergkvist L, Buring JE, Freudenheim JL, Goldbohm E, Hernack L, Kato I, Krogh V, Leitzmann MF, Limburg PJ, Marshall JR, McCullough ML, Miller AB, Rohan TE, Schatzkin A, Shore R, Sieri S, Stampfer MJ, Virtamo J, Weijenberg M, Weijenberg WC, Willett WC, Wolk A, Zhang SM, Smith-Warner SA: Intakes of vitamins A, C and E and use of multivitamin supplements and risk of colon cancer: a pooled analysis of prospective cohort studies. Cancer Causes Control. 2010, 21 (11): 1745-1757. 10.1007/s10552-010-9549-y.PubMedPubMed CentralGoogle Scholar
  73. MacPherson H, Pipingas A, Pase MP: Multivitamin-multimineral supplementation and mortality: a meta-analysis of randomized controlled trials. Am J Clin Nutr. 2013, 97: 437-444. 10.3945/ajcn.112.049304.PubMedGoogle Scholar
  74. Mulholland CA, Benford DJ: What is known about the safety of multivitamin-multimineral supplements for the generally healthy population? Theoretical basis for harm. Am J Clin Nutr. 2007, 85 (Suppl): 318S-322S.PubMedGoogle Scholar
  75. Nunez-Cordoba JM, Martinez-Gonzales MA: Antioxidant vitamins and cardiovascular disease. Curr Top Med Chem. 2011, 11: 1861-1869. 10.2174/156802611796235143.PubMedGoogle Scholar
  76. Evans JR, Lawrenson JG: Antioxidant vitamin and mineral supplements for slowing the progression of age-related macular degeneration (review). Cochrane Database Syst Rev. 2012, 11:CD000254-doi:10.1002/14651858.CD000254.pub3Google Scholar
  77. Riccioni G, D’Orazio N, Salvatore C, Franceschelli S, Pesce M, Speranza L: Carotenoids and Vitamins C and E in the prevention of cardiovascular disease. Int J Vit Nutr Res. 2012, 82 (1): 15-26. 10.1024/0300-9831/a000090.Google Scholar
  78. Fulan H, Changxing J, Baina WX, Wencui Z, Chunqing L, Fan W, Sandan L, Dianjun S, Tong W, Da P, Yashuang Z: Retinol, Vitamins A, C, and E and breast cancer risk: a meta-analysis and meta-regression. Cancer Causes Control. 2011, 22: 1383-1396. 10.1007/s10552-011-9811-y.PubMedGoogle Scholar
  79. Bandera EV, Gifkins DM, Moore DF, McCullough ML, Kushi LH: Antioxidant vitamins and the risk of endrometrial cancer: a dose–response meta-analysis. Cancer Causes Control. 2009, 20 (5): 699-711. 10.1007/s10552-008-9283-x.PubMedGoogle Scholar
  80. Lappe J, Cullen D, Haynatzki G, Recker R, Ahlf R, Thompson K: Calcium and Vitamin D supplementation decrease incidence of stress fractures in female Navy recruits. J Bone Miner Res. 2008, 23: 741-749. 10.1359/jbmr.080102.PubMedGoogle Scholar
  81. Wu CH, Wang CC, Kennedy J: Changes in herb and dietary supplement use in the US adult population: a comparison of the 2002 and 2007 National Health Surveys. Clin Ther. 2011, 33 (11): 1749-1758. 10.1016/j.clinthera.2011.09.024.PubMedGoogle Scholar
  82. Massad SJ, Shier NW, Koceja DM, Ellis NT: High school athletes and nutritional supplements: a study of knowledge and use. Int J Sports Nutr. 1995, 5 (3): 232-245.Google Scholar
  83. Froiland K, Koszewski W, Hingst J, Kopecky L: Nutrition supplement use among college athletes and their sources of information. Int J Sports Nutr Exerc Metabol. 2004, 14: 104-120.Google Scholar
  84. Fitness CONCOSMFCoNatCoSMa: Sport drinks and energy drinks for children and adolescents: are they appropriate?. Pediatrics. 2011, 127: 1182-1189.Google Scholar
  85. Popkin BM, Armstrong LE, Bray GM, Caballero B, Frei B, Willett WC: A new proposed guidance system for beverage consumption in the United States. Am J Clin Nutr. 2006, 83: 529-542.PubMedGoogle Scholar
  86. Lun V, Erdman KA, Fung TS, Reimer RA: Dietary supplementation practices in Canadian high-performance athletes. Int J Sports Nutr Exerc Metabol. 2012, 22: 31-37.Google Scholar
  87. Braun H, Koehler K, Geyer H, Kleinert J, Mester J, Schanzer W: Dietary supplement use among elite young German athletes. Int J Sport Nutr Exerc Metab. 2009, 19: 97-109.PubMedGoogle Scholar
  88. Baylis A, Cameron-Smith D, Burke LM: Inadvertent doping through supplement use by athletes: assessment and management of the risk in Australia. Int J Sport Nutr Exerc Metab. 2001, 11: 365-383.PubMedGoogle Scholar
  89. Park S, Onufrak S, Blanck HM, Sherry B: Characteristics associated with consumption of sports and energy drinks among US adults: National Health Interview Survey, 2010. J Acad Nutr Diet. 2013, 113: 112-119. 10.1016/j.jand.2012.09.019.PubMedPubMed CentralGoogle Scholar
  90. Han E, Powell LM: Consumption patterns of sugar sweetened beverages in the United States. J Acad Nutr Diet. 2013, 113: 43-53. 10.1016/j.jand.2012.09.016.PubMedPubMed CentralGoogle Scholar
  91. Greenwood M, Ferris J, Kreider R, Greenwood L, Byars A: Creatine supplementation patterns and perceived effects in select Division I collegiate athletes. Clin J Sport Med. 2000, 10: 191-194. 10.1097/00042752-200007000-00007.PubMedGoogle Scholar
  92. LaBotz M, Smith BW: Creatine supplement use in an NCAA Division I athletic program. Clin J Sport Med. 1999, 9: 167-169. 10.1097/00042752-199907000-00009.PubMedGoogle Scholar
  93. Rosen O, Sundgot-Borgen J, Maehlum S: Supplement use and nutritional habits in Norwegian elite athletes. Scand J Med Sci Sports. 1999, 9: 28-35.Google Scholar
  94. Scofield DE, Unruh S: Dietary supplement use among adolescent athletes in Central Nebraska and their sources of information. J Strength Cond Res. 2006, 20 (2): 452-455.PubMedGoogle Scholar
  95. Birch R, Nobel D, Greenhaff PL: The influence of dietary creatine supplementation on performance during repeated bouts of maximal isokinetic cycling in man. Eur J Appl Physiol Occ Physiol. 1994, 69: 268-270. 10.1007/BF01094800.Google Scholar
  96. Casey A, Constantin-Teodosiu D, Howell S, Hultman E, Greenhaff PL: Creatine ingestion affects performance and muscle metabolism during maximal exercise in humans. Am J Physiol Endocrinol Metabol. 1996, 271: E31-E37.Google Scholar
  97. Balsom PD, Ekblom B, Soderlund K, Sjodin B, Hultman E: Creatine supplementation and dynamic high-intensity intermittent exercise. Scand J Med Sci Sports. 1993, 3: 143-149.Google Scholar
  98. Gotshalk LA, Volk JS, Staron RS, Denegar CR, Hagerman FC, Kraemer WJ: Creatine supplementation improves muscular performance in older men. Med Sci Sports Exerc. 2002, 34 (3): 537-543. 10.1097/00005768-200203000-00023.PubMedGoogle Scholar
  99. Vandenberghe K, Goris M, VanHecke P, Leemputte MV, VanGerven L, Hespel P: Long-term creatine intake is beneficial to muscle performance during resistance exercise. J Appl Physiol. 1997, 83 (6): 2055-2063.PubMedGoogle Scholar
  100. Istitutes of Medicine: Dietary reference intakes for energy, carbohydrates, fiber, fat, fatty acids, cholesterol, protein, and amino acids. A report of the Panel on Macronutrients, Subcommittee on Upper Levels of Nutrients and Interpretation and Uses of Dietary Reference Intake, and the Standing Committee on the Scientific Evaluation of Dietary Reference Intakes. 2005, Washington DC: National Academies PressGoogle Scholar
  101. Phillips SM: Protein requirements and supplementation in strength sports. Nutrition. 2004, 20: 689-695. 10.1016/j.nut.2004.04.009.PubMedGoogle Scholar
  102. Tarnopolsky M: Protein requirements for endurance athletes. Nutrition. 2004, 20: 662-668. 10.1016/j.nut.2004.04.008.PubMedGoogle Scholar
  103. Pasiakos SM, Austin KG, Lieberman HR, Askew EW: Efficacy and safety of protein supplements for US Armed Forces personnel: consensus statement. J Nutr. 2013, 143 (11): 1811S-1814S. 10.3945/jn.113.176859.PubMedGoogle Scholar
  104. Cermak NM, Res PT, deGroot LCPGM, Saris WHM, vanLoon LJC: Protein supplementation augments the adaptive response of skeletal muscle to resistance-type exercise training: a meta-analysis. Am J Clin Nutr. 2012, 96: 1454-1464. 10.3945/ajcn.112.037556.PubMedGoogle Scholar
  105. Reissig CJ, Strain EC, Griffiths RR: Caffeinated energy drinks–a growing problem. Drug Alcohol Depend. 2009, 99: 1-10. 10.1016/j.drugalcdep.2008.08.001.PubMedGoogle Scholar
  106. Duchan E, Patel ND, Feucht C: Energy drinks: a review of use and safety for athletes. Physician Sportsmed. 2010, 38 (2): 171-179. 10.3810/psm.2010.06.1796.Google Scholar
  107. McLellan TM, Lieberman HR: Do energy drinks contain active compounds other than caffeine?. Nutr Rev. 2012, 70 (12): 730-744. 10.1111/j.1753-4887.2012.00525.x.PubMedGoogle Scholar
  108. Seifert SM, Schaechter JL, Hershorin ER, Lipshultz SE: Health effects of energy drinks on children, adolescents, and young adults. Pediatrics. 2011, 127 (3): 511-528. 10.1542/peds.2009-3592.PubMedPubMed CentralGoogle Scholar
  109. Astorino TA, Roberson DW: Efficacy of acute caffeine ingestion for short-term high-intensity exercise performance: a systematic review. J Strength Cond Res. 2010, 24 (1): 257-265. 10.1519/JSC.0b013e3181c1f88a.PubMedGoogle Scholar
  110. Davis JK, Green JM: Caffeine and anaerobic performance. Ergogenic value and mechanisms of action. Sports Med. 2009, 39 (10): 815-852.Google Scholar
  111. Graham TE: Caffeine and exercise. Metabolism, endurance and performance. Sports Med. 2001, 31 (11): 785-807. 10.2165/00007256-200131110-00002.PubMedGoogle Scholar
  112. Keisler BD, Armsey TD: Caffeine as an ergogenic aid. Curr Sports Med Rep. 2006, 5: 215-219. 10.1097/01.CSMR.0000306510.57644.a7.PubMedGoogle Scholar
  113. Krumbach CJ, Ellis DR, Driskell JA: A report on vitamin and mineral supplement use among university athletes in a division I institution. Int J Sport Nutr. 1999, 9: 416-425.PubMedGoogle Scholar
  114. Petroczi A, Naughton DP, Mazanov J, Holloway A, Bigham J: Performance enhancement with supplements: incongruence between rationale and practice. J Int Soc Sports Nutr. 2007, 4: 19-10.1186/1550-2783-4-19.PubMedPubMed CentralGoogle Scholar
  115. Kristiansen M, Levy-Milne R, Barr S, Flint A: Dietary supplement use by varsity athletes at a Canadian university. Int J Sports Nutr Exerc Metabol. 2005, 15: 195-210.Google Scholar
  116. Pre-publication history

    1. The pre-publication history for this paper can be accessed here:http://www.biomedcentral.com/1472-6882/14/143/prepub

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