Skip to main content Accessibility help
×
Home

Serum 25-hydroxyvitamin D fluctuations in military personnel during 6-month summer operational deployments in Afghanistan

  • Joanne L. Fallowfield (a1), Simon K. Delves (a1), Neil E. Hill (a2), Susan A. Lanham-New (a3), Anneliese M. Shaw (a1), Pieter E. H. Brown (a1), Conor Bentley (a4), Duncan R. Wilson (a2) and Adrian J. Allsopp (a1)...

Abstract

Soldier operational performance is determined by their fitness, nutritional status, quality of rest/recovery, and remaining injury/illness free. Understanding large fluctuations in nutritional status during operations is critical to safeguarding health and well-being. There are limited data world-wide describing the effect of extreme climate change on nutrient profiles. This study investigated the effect of hot-dry deployments on vitamin D status (assessed from 25-hydroxyvitamin D (25(OH)D) concentration) of young, male, military volunteers. Two data sets are presented (pilot study, n 37; main study, n 98), examining serum 25(OH)D concentrations before and during 6-month summer operational deployments to Afghanistan (March to October/November). Body mass, percentage of body fat, dietary intake and serum 25(OH)D concentrations were measured. In addition, parathyroid hormone (PTH), adjusted Ca and albumin concentrations were measured in the main study to better understand 25(OH)D fluctuations. Body mass and fat mass (FM) losses were greater for early (pre- to mid-) deployment compared with late (mid- to post-) deployment (P<0·05). Dietary intake was well-maintained despite high rates of energy expenditure. A pronounced increase in 25(OH)D was observed between pre- (March) and mid-deployment (June) (pilot study: 51 (sd 20) v. 212 (sd 85) nmol/l, P<0·05; main study: 55 (sd 22) v. 167 (sd 71) nmol/l, P<0·05) and remained elevated post-deployment (October/November). In contrast, PTH was highest pre-deployment, decreasing thereafter (main study: 4·45 (sd 2·20) v. 3·79 (sd 1·50) pmol/l, P<0·05). The typical seasonal cycling of vitamin D appeared exaggerated in this active male population undertaking an arduous summer deployment. Further research is warranted, where such large seasonal vitamin D fluctuations may be detrimental to bone health in the longer-term.

Copyright

Corresponding author

*Corresponding author: Dr J. L. Fallowfield, fax +44 2392 504823, email Joanne.Fallowfield258@mod.gov.uk

References

Hide All
1. Holick, MF (2007) Vitamin D deficiency. N Engl J Med 357, 266281.
2. Poskitt, EME, Cole, TJ & Lawson, DEM (1979) Diet, sunlight, and 25-hydroxyvitamin-D in healthy children and adults. Br Med J 1, 221223.
3. Juttman, JR, Visser, TJ, Buurman, C, et al. (1981) Seasonal fluctuations in serum concentrations of vitamin D metabolites in normal subjects. Br Med J 282, 13491352.
4. Committee on Medical Aspects of Food Policy (1998) Report on Health and Social Subjects. No. 49. Nutrition and Bone Health: With Particular Reference to Calcium and Vitamin D. London: HMSO.
5. Swan, G (2004) Findings from the latest national diet and nutrition survey. Proc Nutr Soc 63, 505512.
6. Zittermann, A (2003) Vitamin D in preventive medicine: are we ignoring the evidence? Br J Nutr 89, 552572.
7. Davey, T, Lanham-New, SA, Shaw, AM, et al. (2015) Low serum 25-hydroxyvitamin D is associated with increased risk of stress fracture during Royal Marine recruit training. Osteoporos Int 27, 171179.
8. van Leeuwen, JP, van Driel, M, van den Bemd, GJ, et al. (2001) Vitamin D control of osteoblast function and bone extracellular matrix mineralization. Crit Rev Eukaryot Gene Expr 11, 199226.
9. Darling, AL, Hart, KH, Gibbs, MA, et al. (2014) Greater seasonal cycling of 25-hydroxyvitamin D is associated with increased parathyroid hormone and bone resorption. Osteoporos Int 25, 933941.
10. Ruffing, JA, Cosman, F, Zion, M, et al. (2006) Determinants of bone mass and bone size in a large cohort of physically active young adult men. Nutr Metab 3, 14.
11. Baxter-Jones, ADG, Faulkner, RA & Whiting, SJ (2003) Interaction between nutrition, physical activity and skeletal health. In Nutritional Aspects of Bone Health, pp. 545–564 [SA New, J-P Bonjour, editors]. Cambridge: The Royal Society of Chemistry.
12. Ruohola, JP, Laaksi, I, Ylikomi, T, et al. (2006) Association between serum 25(OH)D concentrations and bone stress fractures in Finnish young men. J Bone Miner Res 21, 14831488.
13. Valimaki, V-V, Alfthan, H, Lehmuskallio, E, et al. (2005) Risk factors for clinical stress fractures in male military recruits: a prospective cohort study. Bone 37, 267273.
14. Heaney, R & Barger-Lux, J (1985) Calcium, bone metabolism, and structural failure. Triangle 24, 91100.
15. Hill, NE, Fallowfield, JL, Delves, SK, et al. (2014) Changes in gut hormones and leptin in military personnel during operational deployment in Afghanistan. Obesity 23, 608614.
16. Fallowfield, JL, Delves, SK, Hill, NE, et al. (2014) Energy expenditure, nutritional status, body composition and physical fitness of Royal Marines during a six-month operational deployment in Afghanistan. Br J Nutr 112, 821829.
17. Brookes ER, Delves SK, Wood AM, et al. (2011) Physical demands of a military operational deployment: dietary intake, estimated energy expenditure, body mass, physical fitness and injury prevalence. In UK Sports and Exercise Medicine Conference – Military Medicine Symposium. ExCel Centre, London, UK.
18. American College of Sports Medicine, American Dietetic Association, and Dieticians of Canada (2000) Joint position statement: nutrition and athletic performance. Med Sci Sports Exerc 32, 21302145.
19. Lohman, TG, Roche, AF & Martorell, R (1998) Anthropometric Standardisation Reference Manual. Champaign, IL: Human Kinetics.
20. Durnin, JV & Womersley, J (1974) Body fat assessed from total body density and its estimation from skinfold thickness: measurements on 481 men and women aged from 16 to 72 years. Br J Nutr 32, 7797.
21. Davey, T, Delves, SK, Allsopp, AJ, et al. (2010) Validation of a bespoke food record card as a method of recording dietary intake in Royal Marine recruits. Proc Nutr Soc 69, E64.
22. James, WPT & Schofield, EC (1990) Human Energy Requirements: A Manual for Planners and Nutritionists. New York: Oxford University Press.
23. Brewer, J, Ramsbottom, R & Williams, C (1988) A progressive shuttle run test for the prediction of maximum oxygen uptake. Br J Sports Med 22, 141144.
24. Scientific Advisory Committee on Nutrition (2017) Military dietary reference values for energy: position paper. https:/www.gov.uk/government/uploads/system/uploads/attachment_data/file/583321/SACN_military_DRVs_for_energy_position_statement.pdf (accessed February 2018).
25. Institute of Medicine (2011) Dietary Reference Intakes for Calcium and Vitamin D. Washington, DC: Institute of Medicine.
26. Shapses, SA & Cifuentes, M (2003) Weight reduction and bone health. In Nutritional Aspects of Bone Health, pp. 589–608 [SA New and J-P Bonjour, editors]. Cambridge: The Royal Society of Chemistry.
27. Villareal, DT, Fontana, L, Das, SK, et al. (2016) Effect of two-year caloric restriction on bone metabolism and bone mineral density in non-obese younger adults: a randomized clinical trial. J Bone Miner Res 31, 4051.
28. Christensen, MH, Lien, EA, Hustad, S, et al. (2010) Seasonal and age-related differences in serum 25-hydroxyvitamin D, 1,25-dihydroxyvitamin D and parathyroid hormone in patients from Western Norway. Scand J Clin Lab Invest 70, 281286.
29. Kremer, R, Campbell, PP, Reinhardt, T, et al. (2008) Vitamin D status and its relationship to body fat, final height, and peak bone mass in young women. J Clin Endocrinol and Metab 94, 6773.
30. Fallowfield JL, Delves SK, Davey T, et al. (2013) Surgeon general’s armed forces feeding project: an evaluation of the reliability of the anthropometric measurement approach. Institute of Naval Medicine Report 2013.006.
31. Pannu, PK, Zhao, Y & Soares, MJ (2016) Reductions in body weight and percent fat mass increase the vitamin D status of obese subjects: a systematic review and metaregression analysis. Nutr Res 36, 201213.
32. Ministry of Defence (2014) Annual medical discharges in the UK regular armed forces 2009/10–2013/14. https://www.gov.uk/governmentuploads/system/uploads/attachment_data/file/445326/20140708-medical_discharges_1_apr_09_31_mar_14_Final-O.pdf (accessed November 2017).
33. Scientific Advisory Committee on Nutrition (2016) Vitamin D and health. https://www.gov.uk/government/publications/sacn-vitamin-d-and-health-report (accessed February 2018).
34. Melamed, ML, Michos, ED, Post, W, et al. (2008) 25-Hydroxyvitamin D levels and the risk of mortality in the general population. Arch Int Med 168, 16291637.
35. Woitge, HW, Scheidt-Nave, C, Kissling, C, et al. (1998) Seasonal variation of biochemical indexes of bone turnover: results of a population-based study. J Clin Endocrinol Metab 83, 6875.
36. Burgi, AA, Gorham, ED, Garland, CF, et al. (2011) High serum 25-hydroxyvitamin D is associated with a low incidence of stress fractures. J Bone Miner Res 26, 23712377.
37. Davey, T, Lanham-New, SA, Shaw, AM, et al. (2015) Fundamental differences in axial and appendicular bone density in stress fractured and uninjured Royal Marine recruits — a matched case–control study. Bone 73, 120126.
38. Ceglia, L, Niramitmahapanya, S, Da Silva Morais, M, et al. (2013) A randomized study on the effect of vitamin D(3) supplementation on skeletal muscle morphology and vitamin D receptor concentration in older women. J Clin Endocrinol Metab 98, E1927E1935.

Keywords

Metrics

Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed