Officially, men were to receive food rations amounting to 4,300 calories daily, meant to fuel the physical demands of soldiering. However, more men needed to be fed as the War progressed, and the German blockade on Allied ships created shortages affecting not only the civilian population but the military as well. This meant that rations had to be reduced throughout the conflict, and the reality in the trenches did not always reflect what was prescribed by the military authorities.