Headward fluid shifts in microgravity push NASA to treat astronauts’ meals as mission-critical

In microgravity, fluids shift toward the head, causing facial puffiness, nasal congestion, and a dulled sense of smell and taste. This fluid shift contributes to reduced appetite and muscle/bone loss, prompting NASA to monitor daily nutrition as a core part of crew health. Despite several hours of exercise, long-duration countermeasures do not fully prevent multisystem deconditioning, a concern that grows with planned Artemis missions and potential Mars voyages, leaving open the need for improved food, countermeasures, or new therapies.