In a video released by NASA on Monday, astronaut Sunita Williams, 59, offered a surprising reason for her weight loss during the five months she was stuck on the International Space Station (ISS) with fellow astronaut Barry “Butch” Wilmore, 61. and viewers also expressed concern for Williams after photos of her looking particularly thin emerged earlier this month.
Alarm! #SunitaWilliams she became so thin. All skin and bones. What was supposed to be an 8-day mission turned into an indefinite one. An astronaut needs 3500-4000 calories a day to maintain his weight. You'll need about 5,000 calories a day to start gaining weight. pic.twitter.com/uTVxuRf0fF
— Kaveri 🇮🇳 (@ikaveri) November 9, 2024
NASA insists stranded astronaut Sunita Williams is safe and well amid growing public concern for her health
The image shows a “truncated” looking woman, suggesting that she has lost a significant amount of weight after spending more than 150 days on the International Space Station. pic.twitter.com/vFEEkfVgDK
— AstroNana (@ImAstroNana) November 9, 2024
In a video posted Monday, Williams attributed his different physique to “fluid displacement” as well as the extra muscle he's built in space. “A lot of changes are happening here. I think there are rumors that I'm losing weight. I'm the same weight I was when I got here,” Williams explained.
“I think things are changing quite a bit, you've probably heard of a fluid shift,” Williams explained. “For people living in space, their heads look a little bigger because the fluid is equalized along the body.” Weightlessness during space flight can often send blood from the lower extremities to a higher point in the body, resulting in the appearance of weight gain.
Williams and Wilmore do their best to stay physically active in space, which is another reason their bodies may look a little different. “Butch and I have been here for several months. We were in training gear. We also have bikes, treadmills and weight lifting equipment,” he said. “I can say that lifting weights, which I don't do all the time, has definitely changed me. My thighs are a little bigger, my butt is a little bigger. We do a lot of squats,” he added, explaining that the treadmill is used to “maintain bone density in our hips and legs.”
Williams and Wilmore have been stranded on the ISS since June, when the Boeing Starliner they arrived on was deemed too faulty and potentially unstable to return to Earth. It was announced in September that the pair are expected to return to Earth in February 2025, marking the eighth month of the astronauts' five-day trip.