Produced by: Mohsin Shaikh
A recent photo of astronaut Sunita Williams has raised alarms, with pulmonologist and Seattle-based expert Dr. Vinay Gupta noting she appears “gaunt” after 150+ days stranded on the ISS.
Williams, 59, was supposed to be on an eight-day mission, but a malfunction in Boeing’s Starliner has kept her in space since June 6, stretching her stay to 152 days.
Dr. Gupta points to her “sunken cheeks,” suggesting she may be experiencing weight loss due to the intense calorie demands of life in space, adding to concerns about her health.
"Her body’s likely in a calorie deficit," Gupta explains, noting that even in a pressurized cabin, basic activities in space burn more calories, accelerating weight loss.
NASA’s 2014 study showed that women astronauts face greater blood plasma loss and higher metabolic demands than men, which may be compounding Williams’s physical strain.
A recent study from Ball University found that women lose muscle faster in microgravity. Williams, like her peers, risks severe muscle loss due to prolonged space exposure.
Despite access to high-calorie foods like cold cuts and pizza, the lack of diet balance complicates efforts to combat muscle loss, according to Dr. Gupta.
The ISS’s lower oxygen levels force the body to work harder, especially in space, intensifying metabolic strain and increasing calorie needs, says Dr. Gupta.
Dr. Gupta cautions that even trained astronauts like Williams face risks in prolonged space missions. “The human body can only adjust so much,” he says, urging vigilance in monitoring her health.