Introduction: Dietary habits and physical exercise have independently been recognized as important contributors to weight loss. However, the relative effect of diet and exercise on body weight is still unclear and warrants further investigation. We investigated the causes related to changes in body mass index (BMI) in a sample of young adult Greek Navy recruits over 10 years. Materials and Methods: We conducted a single-center prospective observational study, including consecutive healthy young adult officers and sailors (>18 years) at the Salamis Naval Base, Salamis, Attiki, Greece. BMI was calculated at the baseline visit. A questionnaire was selected to gather data regarding daily food consumption and daily physical exercise. The participants were followed up for 10 years (2005-2014). Results: Two hundred eighty-four young adults [mean age 31.1 ± 3.1 years; 25 (8.8%) females and 259 (91.2%) males] were included. Baseline median BMI was 24.1 kg/m2, while 10 years later, median BMI was 24.8 kg/m2 (P < 0.001). Physical activity was not significantly related to BMI change (P = 0.153). Multivariate logistic regression analysis showed a significant correlation between BMI increase and frequent fast food consumption (P = 0.044). Conclusions: Frequent fast food consumption is linked with a significant BMI increase, irrespective of physical activity. This has obvious dietary implications and needs to be examined in the general population.
Keywords: BMI; body mass index; naval; obesity; physical exercise; weight loss.