a1 Department of Lifestyle and Participation, National Institute for Health and Welfare, PO Box 30, FI-00271 Helsinki, Finland
a2 Finnish Heart Association, Helsinki, Finland
a3 Department of Chronic Disease Prevention, National Institute for Health and Welfare, Turku, Finland
a4 Centre of Military Medicine, Lahti, Finland
a5 Department of Public Health, University of Helsinki, Helsinki, Finland
Objective To analyse changes in food choices, diet-related risk factors and their association during 6 months of military service.
Design Longitudinal cohort study in Finland, where all men are liable to military service and a clear majority of each age group completes service. Dietary intake data were collected by self-administered questionnaire before and at 6 months of service. Three dietary indices based on food frequencies were developed to characterize the diet: Sugar Index, Fibre Index and Fat Index. Thirteen diet-related risk factors were measured at the beginning and at 6 months of service.
Setting Military environment, two geographically distinct garrisons.
Subjects Male conscripts aged 18–21 years (n 256) performing military service.
Results During 6 months of service, positive changes concerned more frequent use of fibre-rich foods (P = 0·011), improved body composition (BMI, waist circumference, muscle mass, fat mass and percentage body fat, P ≤ 0·003 for all), decreased systolic blood pressure and increased HDL cholesterol (P < 0·001 for both). Negative changes concerned more frequent use of sugar-rich foods and increased total cholesterol, TAG and blood glucose (P < 0·001 for all). The consumption of fibre-rich foods was inversely associated with anthropometric risk factors at baseline and with sugar-rich foods at both time points.
Conclusions Despite more frequent consumption of sweet foods, military service with a unified, nutritionally planned diet, a controlled environment and high physical load has a positive effect on conscripts’ health risk factors. The negative changes in blood lipids and glucose may reflect more varied free-time eating.
(Received April 01 2011)
(Accepted November 13 2011)
(Online publication December 14 2011)