How spaceflight changes astronauts' ability to eat and drink
If humans are to spend more time in space, scientists need to understand how life in microgravity affects eating and drinking
When humans spend extended periods in space, scientists must comprehend how microgravity influences eating and drinking. Picture trying to swallow while congested, with a dulled sense of taste and floating 250 miles above Earth—a scenario common for International Space Station (ISS) astronauts. Spaceflight alters the human body significantly, causing muscles to shrink, bones to lose density, and bodily fluids to shift toward the head.
Decongestion can exacerbate swallowing difficulties, but does microgravity also impact this vital function? As a speech-language pathologist and swallowing disorder researcher, I ponder how to help individuals consume safely. Swallowing involves over 30 muscles and nerves working in precise sequence; it feels effortless when functioning correctly but can become complicated in space.
Although people can swallow while lying down, gravity still provides subtle assistance on Earth. In microgravity, where objects appear weightless, fluids rise toward the head, leading to swelling, nasal congestion, and altered pressure around the mouth and throat. Researchers are beginning to investigate how these changes affect chewing, swallowing, and nutrition.
ISS astronauts often find space food less satisfying due to reduced satisfaction from congestion, altered tastes, and unfamiliar textures. Less food consumption during missions poses challenges for nutrition, essential for muscle strength, immune function, and mental performance. Microgravity and spaceflight may also alter saliva production and oral health, increasing dental problem risks.
Saliva performs multiple tasks, including softening food, forming cohesive masses, and protecting teeth. Dry mouth can make crackers feel like sand and swallowing difficult, even on Earth. During a Mars mission lasting two to three years, astronauts will rely on on-board medical facilities with limited specialists and emergency evacuation options.
Thus, the ability to eat and drink comfortably is crucial for maintaining nutrition and hydration. Early astronauts relied on puréed food from tubes, while today, crews enjoy diverse foods, including tortillas, spicy shrimp cocktails, and fresh fruit. Scientists are developing 3D-printed foods customized for nutritional needs and texture modifications to aid astronauts with chewing or swallowing difficulties.
As humans return to the Moon and venture to Mars, even the simple act of swallowing could impact the success of these missions.
Written by urgent.news from Scientific American's reporting — not their text. Machine-written — may contain errors; check the original before relying on it.
