Associations between whole and low-fat dairy products consumption, physical performance and mental health

BACKGROUND: Military staff are required to be in a proper condition of mental health and weight standards and have a specific level of physical performances (PP). Dairy products are rich sources of essential nutrients. It was demonstrated that Iranians consume much less milk and its products and there is no exception in the military staff. OBJECTIVES: To examine the association between consumption of low or whole-fat dairy and psychological disorders and PP in military personnel. METHODS: This cross-sectional study was conducted in four military zones of Iran. Dairy products intake were evaluated by using a semi-quantitative food-frequency questionnaire (FFQ). The Persian version of Depression, Anxiety, Stress Scale-21 (DASS-21) were used to assess participants’ depression, anxiety and stress and PP were assessed by a 2-mile run, sit-up, push-up and pull-up. RESULTS: There was a significant negative relationship between the tertiles of total and low-fat dairy consumption and depression (OR 0.28, 95% CI 0.10 to 0.79, P <  0.05), and low-fat dairy consumption and stress (OR 0.34, 95% CI 0.13 to 0.93, P <  0.05). Also, there was a positive association between the last tertiles of low-fat dairy consumption and suitable PP (OR 5.28, 95% CI 1.08 to 25.71, P <  0.05). CONCLUSIONS: We concluded that consumption of dairy products and particularly low-fat products are related to less psychological problems and a better PP level.