The overriding theme of the paper is to secure for the soldiers the conditions for the safe performance of their duties by indicating the optimal conditions for their nutrition. Foodstuffs were grouped and characterised. The groups are for use in individual nutrition of soldiers of the Polish Armed Forces serving in peacetime, in situations when they do not have the right to free mass catering.? The principles and opportunities for product substitution have been identified where more expensive products need to be substituted by cheaper ones, due to their hampered availability or seasonality. The principles of rational human nutrition were also presented. The considerations allowed us to conclude that a social group with an increased energy expenditure, performing a specific job to which the soldiers were assigned, should apply the principles of proper nutrition, taking into account an option of foodstuff substitution. Otherwise, soldier’s physical capacity, may be reduced, his concentration span may decline, responsiveness may be reduced and an option of intense physical effort during the performance of official tasks.