Stranded Astronaut Shows Signs of 'Significant' Weight Loss

An American astronaut marooned aboard the International Space Station is showing troubling signs of physical stress, the Daily Mail reported Tuesday.

Sunita Williams, 59, and Barry Wilmore, 61, have spent 152 days in space after the Boeing Starliner failed to return the pair after their start in the ISS on June 6. The crew had prepared for an eight-day mission, yet now can only hope to return in 2025 at the earliest.

Dr. Vinay Gupta, a pulmonologist and veteran in Seattle, told the outlet that while the pair have been positive in TV interviews, photos tell a different story.

"What you're seeing there in that picture is somebody that I think is experiencing the natural stresses of living at very high altitude, even in a pressurized cabin, for extended periods," Gupta said.

"Clearly her cheek appears a bit sunken — and usually it happens when you've had sort of total body weight loss," Gupta added. "I think what I can discern by her face and her cheeks being sunken in is that [she] has probably been at a significant [calorie] deficit for a while."

In a cold environment with zero-gravity conditions, the human body needs to work harder to maintain body temperature. The astronauts also need to exercise close to 2.5 hours a day to prevent muscle and bone loss, which burns further calories.

The photos published on Sept. 24 show Williams and Wilmore eating and smiling, yet Gupta said the definition of her cheek bones points to an unhealthy amount of weight loss.

"I don't think that, based on what I'm at least seeing in the photo, I don't think she's quite at a place where I say her life's in danger," Gupta said. "But I don't think you can look at that photo and say she has sort of healthy body weight."

Williams and Wilmore still need to endure several more months in space as they are not scheduled to return until February on the SpaceX Crew-9 Dragon spacecraft.

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