Objective – To assess the impact of food factors on the performance of functional adaptation of the military who have prior experience of underground work in coal mines. Materials and Methods. The main group included 64 miners aged 30-39, who were in military service in the military unit N of the internal troops of the Ministry of Internal Affairs of the Donetsk Public Republic. In this group we determined the adaptive capacity by Baevsky R.M., Robinson index, Skibinskaya index, and adaptive capacity by Garkavi L.H. The assessment of the food ration and food status of the military was also performed. The control group included 50 soldiers of the same military unit at the age of 30-39 years, living in the same localities, with comparable work experience without underground work in a coal mine. We determined the mean values, reliability was assessed using Student's t-test, relationships were determined using the Pearson’s correlation coefficient. Results. In the main group the indicators of military professional performance in soldiers are lower due to the influence of prior occupational experience. The individual diet of the military does not correspond to their average daily energy consumption. Correction of diet using dietary supplements has led to optimization of adaptation indicators, the absence of differences in standards of physical fitness in soldiers in the main and control groups, that suggests a decrease in the impact of prior occupational experience on adaptation indicators in the initial period of military service. Conclusions. Miners beginning the military service need dietary correction for 3 months. The proposed method increases the functional adaptation indicators.