Table 1 Prevalence (% ± SE) of reported caffeine consumption (≥1 time/week) in military personnel by demographic, lifestyle, and military characteristics
Variable | Strata | Any Caffeine | Coffee | Tea | Soda | Energy Drink | Gums & Medications |
|---|---|---|---|---|---|---|---|
Cohort | All (n = 26,680) | 86.9 ± 0.2 | 68.1 ± 0.3 | 29.2 ± 0.3 | 41.9 ± 0.3 | 29.3 ± 0.3 | 4.3 ± 0.1 |
Gender | Men (n = 23,038) | 87.0 ± 0.2 | 68.3 ± 0.3 | 27.0 ± 0.3 | 43.1 ± 0.3 | 31.3 ± 0.3 | 3.9 ± 0.1 |
Women (n = 3642) | 86.1 ± 0.6 | 66.9 ± 0.8 | 43.5 ± 0.8 | 33.8 ± 0.8 | 16.8 ± 0.6 | 6.5 ± 0.4 | |
p-value (chi-square) | 0.13 | 0.10 | < 0.01 | < 0.01 | < 0.01 | < 0.01 | |
Age | 18–24 years (n = 4660) | 77.6 ± 0.6 | 52.7 ± 0.7 | 24.9 ± 0.6 | 40.8 ± 0.7 | 34.7 ± 0.7 | 3.5 ± 0.3 |
25–29 years (n = 5580) | 85.1 ± 0.5 | 66.1 ± 0.6 | 28.0 ± 0.6 | 38.6 ± 0.7 | 34.2 ± 0.6 | 3.6 ± 0.2 | |
30–39 years (n = 11,030) | 89.5 ± 0.3 | 72.2 ± 0.5 | 29.3 ± 0.4 | 42.7 ± 0.5 | 30.7 ± 0.4 | 4.7 ± 0.2 | |
≥40 years (n = 5275) | 91.4 ± 0.4 | 75.1 ± 0.6 | 34.0 ± 0.7 | 44.8 ± 0.7 | 17.3 ± 0.5 | 4.8 ± 0.3 | |
p-value (chi square/trend) | < 0.01/< 0.01 | < 0.01/< 0.01 | < 0.01/< 0.01 | < 0.01/< 0.01 | < 0.01/< 0.01 | < 0.01/< 0.01 | |
Formal Education | Some high school/High school graduate (n = 3879) | 79.9 ± 0.6 | 55.0 ± 0.8 | 22.9 ± 0.7 | 45.0 ± 0.8 | 38.8 ± 0.8 | 4.1 ± 0.3 |
Some college/Associate’s degree (n = 11,378) | 86.4 ± 0.3 | 67.1 ± 0.4 | 28.2 ± 0.4 | 43.1 ± 0.5 | 35.1 ± 0.5 | 4.8 ± 0.2 | |
Bachelor’s/Graduate degree (n = 11,417) | 89.6 ± 0.3 | 73.5 ± 0.4 | 32.3 ± 0.4 | 39.6 ± 0.5 | 20.3 ± 0.4 | 3.8 ± 0.2 | |
p-value (chi square/trend) | < 0.01/< 0.01 | < 0.01/< 0.01 | < 0.01/< 0.01 | < 0.01/< 0.01 | < 0.01/< 0.01 | < 0.01/0.06 | |
Race / Ethnicity | White (n = 16,316) | 90.9 ± 0.2 | 73.0 ± 0.3 | 29.0 ± 0.4 | 44.4 ± 0.4 | 31.4 ± 0.4 | 4.5 ± 0.2 |
Hispanic (n = 4227) | 83.5 ± 0.6 | 65.2 ± 0.7 | 25.2 ± 0.8 | 39.2 ± 0.8 | 30.4 ± 0.7 | 3.6 ± 0.3 | |
Black (n = 2966) | 72.2 ± 0.8 | 46.5 ± 0.9 | 30.7 ± 0.8 | 34.4 ± 0.9 | 18.8 ± 0.7 | 4.6 ± 0.4 | |
Other (n = 3171) | 84.5 ± 0.6 | 67.1 ± 0.8 | 34.6 ± 0.8 | 39.4 ± 0.9 | 27.1 ± 0.8 | 3.7 ± 0.3 | |
p-value (chi-square) | < 0.01 | < 0.01 | < 0.01 | < 0.01 | < 0.01 | 0.03 | |
Body mass index | < 25.0 kg/m2 (n = 7856) | 84.4 ± 0.4 | 64.9 ± 0.5 | 30.6 ± 0.5 | 39.4 ± 0.6 | 24.7 ± 0.5 | 3.5 ± 0.2 |
25.0–29.9 kg/m2 (n = 13,897) | 87.5 ± 0.3 | 69.4 ± 0.4 | 28.3 ± 0.4 | 41.2 ± 0.4 | 30.3 ± 0.4 | 4.2 ± 0.2 | |
≥30.0 kg/m2 (n = 4424) | 89.4 ± 0.5 | 69.6 ± 0.7 | 29.3 ± 0.7 | 48.4 ± 0.8 | 34.3 ± 0.7 | 5.9 ± 0.3 | |
p-value (chi square/trend) | < 0.01/< 0.01 | < 0.01/< 0.01 | < 0.01/0.30 | < 0.01/< 0.01 | < 0.01/< 0.01 | < 0.01/< 0.01 | |
Aerobic exercise duration | ≤90 min/wk. (n = 7286) | 84.0 ± 0.4 | 66.5 ± 0.6 | 27.1 ± 0.5 | 42.5 ± 0.6 | 28.3 ± 0.5 | 4.3 ± 0.2 |
91–180 min/wk. (n = 7285) | 90.0 ± 0.4 | 71.4 ± 0.5 | 31.1 ± 0.5 | 45.7 ± 0.6 | 28.9 ± 0.5 | 4.2 ± 0.2 | |
181–300 min/wk. (n = 5869) | 88.9 ± 0.4 | 70.5 ± 0.6 | 30.1 ± 0.6 | 42.4 ± 0.6 | 30.1 ± 0.6 | 4.0 ± 0.3 | |
≥301 min/wk. (n = 6240) | 84.9 + 0.5 | 65.6 ± 0.6 | 28.7 ± 0.6 | 36.2 ± 0.6 | 30.4 ± 0.6 | 4.5 ± 0.3 | |
p-value (chi square/trend) | < 0.01/0.49 | < 0.01/0.62 | < 0.01/0.09 | < 0.01/< 0.01 | 0.03/< 0.01 | 0.57/0.64 | |
Resistance training frequency | ≤45 min/wk. (n = 7776) | 85.5 ± 0.4 | 66.4 ± 0.5 | 30.9 ± 0.5 | 47.4 ± 0.6 | 24.2 ± 0.5 | 4.5 ± 0.2 |
46–135 min/wk. (n = 6257) | 90.1 ± 0.4 | 71.7 ± 0.6 | 32.1 ± 0.6 | 46.0 ± 0.6 | 26.7 ± 0.6 | 4.3 ± 0.3 | |
136–300 min/wk. (n = 6581) | 89.0 ± 0.4 | 71.3 ± 0.6 | 29.3 ± 0.6 | 39.5 ± 0.6 | 31.1 ± 0.6 | 4.2 ± 0.3 | |
≥301 min/wk. (n = 6066) | 82.9 ± 0.5 | 63.1 ± 0.6 | 24.0 ± 0.5 | 33.0 ± 0.6 | 36.8 ± 0.6 | 4.0 ± 0.3 | |
p-value (chi square/trend) | < 0.01/< 0.01 | < 0.01/< 0.01 | < 0.01/< 0.01 | < 0.01/< 0.01 | < 0.01/< 0.01 | 0.46/0.11 | |
Smoking | Never (n = 16,706) | 84.9 ± 0.3 | 63.7 ± 0.4 | 29.7 ± 0.4 | 39.5 ± 0.4 | 24.5 ± 0.3 | 4.0 ± 0.2 |
Former (n = 4767) | 93.9 ± 0.3 | 79.9 ± 0.6 | 29.4 ± 0.7 | 44.1 ± 0.7 | 35.0 ± 0.7 | 5.2 ± 0.3 | |
Smoker (n = 4511) | 93.6 ± 0.4 | 77.1 ± 0.6 | 29.9 ± 0.7 | 51.7 ± 0.7 | 43.6 ± 0.7 | 4.8 ± 0.3 | |
p-value (chi-square) | < 0.01 | < 0.01 | 0.88 | < 0.01 | < 0.01 | < 0.01 | |
Smokeless tobacco use | Never (n = 20,378) | 86.4 ± 0.2 | 66.1 ± 0.3 | 30.6 ± 0.3 | 41.6 ± 0.3 | 26.2 ± 0.3 | 4.3 ± 0.1 |
Former (n = 2047) | 95.7 ± 0.4 | 82.9 ± 0.8 | 27.1 ± 1.0 | 43.7 ± 1.1 | 38.1 ± 1.1 | 4.8 ± 0.5 | |
Smoker (n = 3114) | 94.3 ± 0.4 | 79.2 ± 0.7 | 26.4 ± 0.8 | 48.5 ± 0.9 | 47.8 ± 0.9 | 4.6 ± 0.4 | |
p-value (chi-square) | < 0.01 | < 0.01 | < 0.01 | < 0.01 | < 0.01 | 0.43 | |
Alcohol intake | 0 ml/wk. (n = 8372) | 73.8 ± 0.5 | 50.8 ± 0.5 | 23.3 ± 0.5 | 35.1 ± 0.5 | 23.9 ± 0.5 | 3.8 ± 0.2 |
0.23–24.85 ml/wk. (n = 6132) | 89.5 ± 0.4 | 70.2 ± 0.6 | 31.4 ± 0.6 | 41.2 ± 0.6 | 25.3 ± 0.6 | 3.9 ± 0.2 | |
24.86–71.69 ml/wk. (n = 6108) | 93.3 ± 0.3 | 76.0 ± 0.5 | 31.5 ± 0.6 | 45.1 ± 0.6 | 31.9 ± 0.6 | 4.4 ± 0.3 | |
≥71.70 ml/wk. (n = 6067) | 95.9 ± 0.3 | 81.9 ± 0.5 | 32.9 ± 0.6 | 48.7 ± 0.6 | 38.3 ± 0.6 | 5.0 ± 0.3 | |
p-value (chi square/trend) | < 0.01/< 0.01 | < 0.01/< 0.01 | < 0.01/< 0.01 | < 0.01/< 0.01 | < 0.01/< 0.01 | < 0.01/< 0.01 | |
Sleep | ≥7 h/night (n = 9702) | 87.9 ± 0.3 | 69.3 ± 0.5 | 29.0 ± 0.5 | 40.8 ± 0.5 | 26.2 ± 0.4 | 3.3 ± 0.2 |
5–6 h/night (n = 10,027) | 90.9 ± 0.3 | 71.5 ± 0.5 | 30.6 ± 0.5 | 46.7 ± 0.5 | 34.7 ± 0.5 | 5.1 ± 0.2 | |
< 4 h/night (n = 1090) | 84.2 ± 1.1 | 65.4 ± 1.4 | 31.6 ± 1.4 | 43.7 ± 1.5 | 35.3 ± 1.4 | 8.2 ± 0.8 | |
p-value (chi-square/linear trend) | < 0.01/0.01 | < 0.01/0.48 | 0.02/< 0.01 | < 0.01/< 0.01 | < 0.01/< 0.01 | < 0.01/< 0.01 | |
Rank | Junior enlisted, E1-E4 (n = 2496) | 74.9 ± 0.9 | 49.8 ± 1.0 | 24.7 ± 0.9 | 40.5 ± 1.0 | 33.1 ± 0.9 | 3.4 ± 0.4 |
Mid enlisted E5-E6 (n = 11,609) | 85.2 ± 0.3 | 64.5 ± 0.4 | 27.8 ± 0.4 | 42.8 ± 0.5 | 36.4 ± 0.4 | 4.7 ± 0.2 | |
Senior enlisted E7-E9 (n = 4365) | 91.0 ± 0.4 | 74.4 ± 0.7 | 28.9 ± 0.7 | 44.7 ± 0.8 | 29.6 ± 0.7 | 4.9 ± 0.3 | |
Warrant officer (n = 576) | 93.2 ± 1.0 | 78.1 ± 1.7 | 29.7 ± 1.9 | 39.2 ± 2.0 | 27.3 ± 1.9 | 4.7 ± 0.9 | |
Junior officer, O1-O3 (n = 3891) | 88.3 ± 0.5 | 73.6 ± 0.7 | 31.9 ± 0.7 | 35.3 ± 0.8 | 21.7 ± 0.7 | 3.2 ± 0.3 | |
Senior officer, O4-O7 (n = 3742) | 92.8 ± 0.4 | 77.2 ± 0.7 | 34.2 ± 0.8 | 43.7 ± 0.8 | 12.9 ± 0.5 | 3.8 ± 0.3 | |
p-value (chi-square) | < 0.01 | < 0.01 | < 0.01 | < 0.01 | < 0.01 | < 0.01 | |
Occupational assignment group | Combat arms (n = 6451) | 89.0 ± 0.4 | 72.5 ± 0.6 | 27.7 ± 0.6 | 41.4 ± 0.6 | 31.9 ± 0.6 | 3.8 ± 0.2 |
Combat support (n = 10,424) | 86.3 ± 0.3 | 66.2 ± 0.5 | 29.0 ± 0.4 | 42.1 ± 0.5 | 31.1 ± 0.5 | 4.2 ± 0.2 | |
Combat service support (n = 9132) | 86.3 ± 0.4 | 67.6 ± 0.5 | 30.6 ± 0.5 | 42.0 ± 0.5 | 25.7 ± 0.5 | 4.6 ± 0.2 | |
p-value (chi-square) | < 0.01 | < 0.01 | < 0.01 | 0.65 | < 0.01 | 0.04 | |
Service branch | Air Force (n = 9788) | 86.3 ± 0.3 | 65.5 ± 0.5 | 29.7 ± 0.5 | 43.1 ± 0.5 | 28.3 ± 0.5 | 3.9 ± 0.2 |
Army (n = 7935) | 87.0 ± 0.4 | 69.0 ± 0.5 | 28.1 ± 0.5 | 39.8 ± 0.5 | 29.3 ± 0.5 | 4.5 ± 0.2 | |
Marine Corps (n = 3194) | 84.8 ± 0.6 | 65.5 ± 0.8 | 23.8 ± 0.8 | 40.7 ± 0.9 | 38.8 ± 0.9 | 3.6 ± 0.3 | |
Navy (n = 5763) | 88.8 ± 0.4 | 72.8 ± 0.6 | 33.0 ± 0.6 | 43.3 ± 0.7 | 25.9 ± 0.6 | 5.0 ± 0.3 | |
p-value (chi-square) | < 0.01 | < 0.01 | < 0.01 | < 0.01 | < 0.01 | < 0.01 |