Military training and pregnancy increase women’s nutritional needs, specifically for vitamin D, calcium, iron, folate, and iodine. While OPSS always recommends choosing whole foods first, sometimes it can be difficult to get enough of those nutrients through food alone. When nutrient needs are higher than normal or when nutrient-rich foods aren’t available, vitamin and mineral supplements can help women to restore nutrient levels in their bodies. Just remember that you don’t need supplements unless you have known nutrient deficiencies, so talk to your healthcare provider before taking any supplement.

Military training

Intense daily physical training, such as during basic training, increases your calcium and iron needs and has been associated with lower levels of vitamin D in the blood.

Note: In general, service members are not permitted to bring supplements to basic training unless prescribed by a healthcare provider. Regulations regarding supplement use during other types of training may vary by school and service. Contact your Command for specific directions.

Vitamin D and Calcium. Low levels of vitamin D and calcium in the body are associated with weaker bones and increased risk of stress fractures. Studies with female Army and Navy recruits suggest that supplementing diets with calcium and vitamin D during basic training can improve bone health and protect against stress fractures. However, more research is needed to determine if and how much supplemental vitamin D and calcium is effective for preventing stress fractures. Visit the National Institute of Arthritis and Musculoskeletal and Skin Diseases for more information about calcium and vitamin D.

Iron. Women are at increased risk for iron deficiency due to menstrual bleeding. Iron deficiency can affect your performance and make it difficult to complete training. If you can’t get enough iron from food, iron supplements can help. For more information about iron and training, see HPRC’s “Add pep to your training envIRONment.”

Pregnancy and lactation

If you’re pregnant or plan to become pregnant soon, talk with your healthcare provider about taking a multivitamin/mineral (prenatal) supplement that contains folic acid, iron, and iodine. It’s important to get enough folic acid (from food and/or supplements) daily before conceiving to reduce the risk of birth defects. For more information, read the OPSS article about supplements during pregnancy.

Breastfeeding increases certain nutrient needs, such as vitamin A and iodine. However, there’s no consensus on the use of individual or multi-vitamin/mineral supplements during lactation. These vitamins and minerals usually can be obtained by eating a variety of nutrient-rich foods. A healthcare provider can determine individual supplement needs, if necessary, for a breastfeeding mother.  

Note: There is very little research on the safety of herbal or botanical dietary supplement ingredients during pregnancy or lactation, and some may be unsafe. In addition, pregnant and breastfeeding women should be aware of all sources of caffeine in their diet from foods, beverages, supplements, and medications. According to the American College of Obstetricians and Gynecologists, consuming less than 200 mg of caffeine a day during pregnancy and less than 300 mg a day while breastfeeding is safe.

Debrief

Vitamin and mineral supplements can help female military members meet their nutritional needs during times of increased nutrient use or when unable to meet their needs from foods. However, follow these steps before taking any supplement:

  • Talk to your healthcare provider. Only use supplements if you have known nutrient deficiencies or greater nutrient needs that can’t be met with food alone, and only use them under the supervision of your healthcare provider.
  • Take the recommended dosage. Taking more can cause some nutrients to build up to unsafe amounts in your body.
  • Continue to eat nutrient-rich foods. Although supplements can provide essential nutrients, it’s better to try to get those nutrients from whole foods to optimize performance and overall health. 

Updated 26 February 2019

References

American Academy of Pediatrics. (2014). Iodine deficiency, pollutant chemicals, and the thyroid: New information on an old problem. Pediatrics, 133(6), 1163–1166. doi:10.1542/peds.2014-0900

American College of Obstetricians and Gynecologists. (2016). Breastfeeding your baby.   Retrieved 1 May 2019 from https://www.acog.org/Patients/FAQs/Breastfeeding-Your-Baby

American College of Obstetricians and Gynecologists. (2018). Nutrition during pregnancy.   Retrieved 1 May 2019 from https://www.acog.org/Patients/FAQs/Nutrition-During-Pregnancy

Andersen, N. E., Karl, J. P., Cable, S. J., Williams, K. W., Rood, J. C., Young, A. J., . . . McClung, J. P. (2010). Vitamin D status in female military personnel during combat training. Journal of the International Society of Sports Nutrition, 7(1). doi:10.1186/1550-2783-7-38

Bailey, R. L., Gahche, J. J., Miller, P. E., Thomas, P. R., & Dwyer, J. T. (2013). Why U.S. adults use dietary supplements. JAMA Internal Medicine, 173(5), 355–361. doi:10.1001/jamainternmed.2013.2299

Barnes, K. R., Tchandja, J. N., Webber, B. J., Federinko, S. P., & Cropper, T. L. (2015). The effects of prenatal vitamin supplementation on operationally significant health outcomes in female Air Force trainees. Military Medicine, 180(5), 554–558. doi:10.7205/milmed-d-14-00258

Becker, D. V., Braverman, L. E., Delange, F., Dunn, J. T., Franklyn, J. A., Hollowell, J. G., . . . Rovet, J. F. (2006). Iodine supplementation for pregnancy and lactation—United States and Canada: Recommendations of the American Thyroid Association. Thyroid, 16(10), 949–951. doi:10.1089/thy.2006.16.949

Committee on Mineral Requirements for Cognitive and Physical Performance of Military Personnel, Committee on Military Nutrition Research, & Board, F. a. N. (2006). Mineral recommendations for military performance Mineral Requirements for Military Personnel: Levels Needed for Cognitive and Physical Performance During Garrison Training (pp. 58–190). Washington, DC: National Academies Press.

Gaffney-Stomberg, E., Lutz, L. J., Rood, J. C., Cable, S. J., Pasiakos, S. M., Young, A. J., & McClung, J. P. (2014). Calcium and vitamin D supplementation maintains parathyroid hormone and improves bone density during initial military training: A randomized, double-blind, placebo controlled trial. Bone, 68, 46–56. doi:10.1016/j.bone.2014.08.002

Greenwood, M. R. C., & Oria, M. (Eds.). (2008). Use of Dietary Supplements by Military Personnel. Washington, DC: National Academies Press.

Jacobson, I. G., Horton, J. L., Smith, B., Wells, T. S., Boyko, E. J., Lieberman, H. R., . . . Smith, T. C. (2012). Bodybuilding, energy, and weight-loss supplements are associated with deployment and physical activity in U.S. military personnel. Annals of Epidemiology, 22(5), 318–330. doi:10.1016/j.annepidem.2012.02.017

Kaiser, L. L., & Campbell, C. G. (2014). Practice paper of the Academy of Nutrition and Dietetics abstract: Nutrition and lifestyle for a healthy pregnancy outcome. Journal of the Academy of Nutrition and Dietetics, 114(9), 1447. doi:10.1016/j.jand.2014.07.001

Kirkham, C., Harris, S., & Grzybowski, S. (2005). Evidence-based prenatal care: Part I. General prenatal care and counseling issues. American Family Physician, 71(7), 1307–1316.

Knapik, J. J., Steelman, R. A., Hoedebecke, S. S., Farina, E. K., Austin, K. G., & Lieberman, H. R. (2014). A systematic review and meta-analysis on the prevalence of dietary supplement use by military personnel. BMC Complementary and Alternative Medicine, 14(1), 143. doi:10.1186/1472-6882-14-143

Lappe, J., Cullen, D., Haynatzki, G., Recker, R., Ahlf, R., & Thompson, K. (2008). Calcium and vitamin D supplementation decreases incidence of stress fractures in female Navy recruits. Journal of Bone and Mineral Research, 23(5), 741–749. doi:10.1359/jbmr.080102

Leung, A. M., Pearce, E. N., Braverman, L. E., & Stagnaro-Green, A. (2014). AAP recommendations on iodine nutrition during pregnancy and lactation. Pediatrics, 134(4), e1282–e1282. doi:10.1542/peds.2014-2111A

Lutz, L. J., Karl, J., Rood, J. C., Cable, S. J., Williams, K. W., Young, A. J., & McClung, J. P. (2012). Vitamin D status, dietary intake, and bone turnover in female Soldiers during military training: A longitudinal study. Journal of the International Society of Sports Nutrition, 9(1), 38. doi:10.1186/1550-2783-9-38

McClung, J. P., Karl, J. P., Cable, S. J., Williams, K. W., Nindl, B. C., Young, A. J., & Lieberman, H. R. (2009). Randomized, double-blind, placebo-controlled trial of iron supplementation in female soldiers during military training: Effects on iron status, physical performance, and mood. The American Journal of Clinical Nutrition, 90(1), 124–131. doi:10.3945/ajcn.2009.27774

Pasricha, S.-R., Low, M., Thompson, J., Farrell, A., & De-Regil, L.-M. (2014). Iron supplementation benefits physical performance in women of reproductive age: A systematic review and meta-analysis. Journal of Nutrition, 144(6), 906–914. doi:10.3945/jn.113.189589

Picciano, M. F., & McGuire, M. K. (2009). Use of dietary supplements by pregnant and lactating women in North America. American Journal of Clinical Nutrition, 89(2), 663S–667S. doi:10.3945/ajcn.2008.26811B

Pillitteri, J. L., Shiffman, S., Rohay, J. M., Harkins, A. M., Burton, S. L., & Wadden, T. A. (2008). Use of dietary supplements for weight loss in the United States: Results of a national survey. Obesity, 16(4), 790–796. doi:10.1038/oby.2007.136

Stagnaro-Green, A., Abalovich, M., Alexander, E., Azizi, F., Mestman, J., Negro, R., . . . Wiersinga, W. (2011). Guidelines of the American Thyroid Association for the diagnosis and management of thyroid disease during pregnancy and postpartum. Thyroid, 21(10), 1081–1125. doi:10.1089/thy.2011.0087

Subcommittee on Nutrition During Lactation, Committee on Nutritional Status During Pregnancy and Lactation, Food and Nutrition Board, Institute of Medicine, & National Academy of Sciences. (1991). Meeting maternal nutrient needs during lactation Nutrition During Lactation (pp. 213–235). Washington, DC: National Academy Press.

Tenforde, A. S., Sayres, L. C., Sainani, K. L., & Fredericson, M. (2010). Evaluating the relationship of calcium and vitamin d in the prevention of stress fracture injuries in the young athlete: A review of the literature. Pm&R, 2(10), 945–949. doi:10.1016/j.pmrj.2010.05.006

U.S. Centers for Disease Control and Prevention. (2012). Second National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population. National Center for Environmental Health, Atlanta, GA, Retrieved from:

U.S. Centers for Disease Control and Prevention. (2018). Folic acid.   Retrieved 1 May 2019 from https://www.cdc.gov/ncbddd/folicacid/about.html

Wentz, L., Liu, P.-Y., Haymes, E., & Ilich, J. Z. (2011). Females have a greater incidence of stress fractures than males in both military and athletic populations: A systemic review. Military Medicine, 176(4), 420–430. doi:10.7205/milmed-d-10-00322