What a fever costs the body
A fever is a regulated rise in body temperature, triggered as the immune system responds to infection. Keeping the body warmer takes energy: metabolism speeds up, and the heart and breathing may work harder. The immune response itself also uses resources. Skipping food does not make the infection run out of fuel; it mainly means the body has less coming in while it is under strain.
Appetite can change without becoming a treatment
Illness often dulls appetite, and a short spell of eating less is not the same as deliberately fasting. The useful approach is usually to eat what feels manageable rather than force a full meal. Small portions of familiar foods can be easier than a large plate, while fluids matter especially because fever and sweating can increase fluid loss.
Food does not directly cure the infection or guarantee a faster recovery. But intentionally withholding it offers no established advantage—and may leave someone weaker, particularly if poor intake continues. The practical point is simple: let appetite guide how much to eat, not the idea that hunger will starve the illness.
