28/03/2026
How Your Gut Shuts Down Hunger When Parasites Strike
When you are fighting a parasitic infection, you often lose your appetite. Scientists have traced this protective behavior to a two step conversation happening inside your gut lining. Special sensory cells called tuft cells detect parasites and release a chemical messenger. At first, this happens in quick bursts, but as the infection progresses, these cells switch to a slow, continuous leak of the chemical. This sustained signal activates neighboring hormone releasing cells, which flood the system with serotonin. High enough levels of this brain signaling chemical stimulate the vagus nerve to tell the brain to shut down hunger signals. This discovery explains why you might feel fine initially but lose your appetite later in an infection, revealing how the gut and brain collaborate to prioritize healing over eating when under attack.