Space does strange things to the human body. Just ask Scott Kelly, a former NASA astronaut who spent 340 days circling the Earth in a rocket. All kinds of things impacted him, including the microgravity, radiation exposure, and space food. Scott discovered that his face became puffy because the liquid in his body distributed more evenly. In fact, the fluid, which moved from his legs to head would fit into a two liter soda bottle (as per Business Insider). 

Scott’s experience in space was detailed in NASA’s Twins Study, where 10 groups of researchers looked at what changes the human body — physiological, molecular, and cognitive — encountered when in space. Data was collected from Scott’s yearlong mission and his twin brother, retired astronaut Mark Kelly, who was on Earth during his sibling’s time in space. Mark provided a baseline for researchers who could compare his measurements and reactions with his brother’s.

While the extreme environment altered Scott’s body, the study concluded that humans who engage in similar space travel can remain healthy, reported Science. The Twins Study demonstrated the resilience and robustness of how a human body can adapt to a multitude of changes induced by a spaceflight environment, per NASA in a press release. However, more study is needed to determine any long-term consequences of space travel, especially since long missions are rare.

Visiting space can also make you taller — about 3% more. That means that a 6-foot-tall astronaut might add 2 inches to their frame, according to Scientific American.

Microgravity impacts the human body

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