Stranded NASA astronaut Sunita Williams expresses concern about her weight loss in space

Stranded astronaut Sunita Williams said growing concerns about her health were nothing more than “rumours” – as she attributed the change in her appearance to “fluid shifts”.

Williams, 59, sparked concern last week when she appeared gaunt in a NASA photo, with sunken cheeks and a noticeably thinner frame.

The astronaut tried to allay her worries when she spoke to the New England Sports Network Clubhouse Kids show on Tuesday, saying she was healthy.

“You know, people in space make their heads look a little bigger because the fluid is evenly distributed along the body,” she explained.

“I think things are shifting quite a bit, you’ve probably heard of a fluid shift,” she added, referring to the phenomenon that occurs to astronauts in space.

According to NASA, half of all American astronauts aboard the International Space Station experience fluid shifts, where fluid moves upward in the body and increases volume and pressure in the head.

Williams also disputed claims that she was losing too much weight in space, saying she had actually gained muscle since her return trip was delayed until February.

“My thighs are a little bigger, my butt is a little bigger,” she said. “We do a lot of squats.”

But a NASA official directly involved in Williams’ mission told The Post last week that the astronaut had “lost a lot of weight.”

““The pounds have melted off her and she is just skin and bones,” he said. “So helping her stabilize and hopefully reverse the weight loss is a priority.”

The source said Williams, who was only supposed to stay in space for eight days, was unable to keep up with the high-calorie diet astronauts must eat.

NASA doctors began working with Williams about a month ago to help her pack on the pounds — even before the viral images sparked global concern about her health, the source said.

NASA has stressed that there are no major concerns about Williams’ health or weight.

“All NASA astronauts aboard the International Space Station undergo routine medical examinations,” the agency said in a statement.

“They are being monitored by dedicated flight surgeons and are in good health.”

Williams and fellow astronaut Barry Wilmore have been stuck on the ISS for more than five months after their Boeing Starliner experienced technical problems and returned to Earth empty.

A SpaceX Crew Dragon capsule will bring them home, but return is not scheduled until February 2025.