Doctors have raised concerns about astronaut Sunita Williams’ health after looking noticeably frail in a new photo.

NASA published photographs of astronaut Williams, 59, and astronaut Butch Wilmore, 62, cautiously walking and exchanging greetings with NASA staff members following a series of medical examinations after their extended nine-month space journey.

Medical professionals specifically highlighted Williams’ noticeably slender wrists, which they indicated to DailyMail.com could indicate rapid weight loss, muscle atrophy in her arms, and a decrease in bone density.

The specialists also observed that the intravenous (IV) line in Williams’ wrist is probably being used to replenish fluids and electrolytes since the absence of gravity in space deceives the body into discarding essential fluids, leading to dehydration.

Striking before and after pictures of Williams show her with noticeably grayer hair, deeper wrinkles, and a more gaunt face. 

But experts suggest the fact that the duo are already walking less than 24 hours after returning is promising – some feared they may not regain that ability for days.

Sunita Williams (pictured here in the center) sparked health concerns over her ‘visibly thin’ appearance as she and Butch Wilmore finally returned to Earth after nine months in space

Doctors pointed to Williams’ wrist as a sign of health issues, both due to how thin it is and the IV sticking out of it

Dr John Jaquish, a biomedical engineer in at Jaquish Biomedical, told DailyMail.com: ‘That amount of time in space is crushing.’ 

Williams and Wilmore were only supposed to spend eight days on the International Space Station (ISS) when they blasted off on June 5.

But a scourge of technical issues with their spacecraft, Boeing’s Starliner, ultimately drove NASA to delay their return until they could hitch a ride home on a safer ship.

They spent 286 days aboard the ISS until splashing down Tuesday. Both astronauts were immediately lifted on to stretchers and taken for medical evaluations.

Dr Olalekan Otulana, a general practitioner at Cassioburt Court in the UK, told DailyMail.com: ‘Sunita Williams’ visibly thin wrists could indicate muscular atrophy, particularly in the forearm muscles, which are less used in space.’ 

Dr Jaquish also noted Williams has also likely lost weight and bone density. 

He said: ‘Without gravity, you don’t digest food as well. Compromising your ability to digest food is certainly going to contribute to muscle loss and bone loss on its own.’ 

He also noted the astronauts’ lack of muscle movement from basic activity like getting up to walk around could her tendons and ligaments to shrink as well. 

Dr Vinay Gupta, a pulmonologist and Air Force veteran, told DailyMail.com: ‘I don’t think people realize that you need gravity to exercise your muscles, and if you don’t have gravity, your muscles have nothing to have resistance against.’ 

Williams, pictured right shortly after landing, is likely suffering from muscular atrophy and bone density loss, experts told DailyMail.com

Muscular atrophy and bone density both leave sufferers more prone to fractures from simple movements or light injuries, reducing their mobility. 

Dr Gupta also notes that women tend to be more prone to bone density loss due to having smaller, lighter bones, as well as a decline in protective hormones like estrogen after menopause.

‘I’m not surprised that we saw and we’re seeing that she clearly has some issues there, because women tend to be impacted by these things more than men,’ he said.  

Williams’ apparent weight loss could also be an effect of living in a zero-gravity environment for nine months. ‘You don’t digest your food as well in space,’ Dr Jaquish said. 

‘When your stomach is upside down, it doesn’t move food as efficiently through the digestive system, so they have to eat less and wait longer,’ he added.

This may lead to the stomach shrinking and being unable to take in enough calories to maintain her weight. 

Dr David Shafer, plastic surgeon and owner of Shafer Clinic and Advitam metabolic wellness clinic in New York, told DailyMail.com: ‘While great strides have been made in space-friendly food, sustaining on that diet for a very long time is likely not going to provide your body with optimal nutrition that you’d get from eating a more varied diet on Earth.’

Experts suggested Williams (pictured here) and Wilmore likely will have to regain their balance after so long in space

In November, an unnamed NASA employee who is ‘directly involved with the mission’ told the New York Post that Williams was ‘unable to keep up with the high-caloric diets that astronauts must consume’ while on the ISS. 

Dr Jaquish estimates it will take about three weeks for Williams to regain ‘normal digestive function,’ and leading up to that, she and Wilmore will ‘have to reintroduce food very slowly.’

Their starting foods will also likely be animal products like butter and meat since they are high in calories and essential nutrients like protein and fat. 

Another sign of nutritional deficiencies could be the IV in Williams’ wrist. 

Dr Otulana said: ‘The IV in her wrist is most likely for rehydration and electrolyte balance. This is very important after prolonged space flight to prevent dizziness and aid circulation in Earth’s gravity.’

Dr Jaquish noted other NASA personnel seems to be holding on to Williams and Wilmore in the newly released images, suggesting balance issues.  

‘Someone is hanging on to them because they could just easily tip over. They have lost their ability to balance themselves in the Earth’s gravitational field,’ he added. 

Carole Lieberman, a psychiatrist in Beverly Hills, told DailyMail.com Williams’ apparent weight loss may not have been entirely caused by physical issues.

She said: ‘These astronauts have been in space for nine months, when they were only supposed to be up there for 10 days. 

‘For most of this time, they couldn’t be sure they would ever be rescued, which is tremendously stressful.

Wilmore is pictured here with what looks to be an IV in his arm

‘Sunita Williams put on a brave face and told everyone she was happy to have this extra time in space, but the prospect of facing a slow death in a space capsule is a thing that nightmares are made of – and it took a toll on her psyche.

‘Worrying about being rescued is stressful enough, but then pretending to herself and others that she is not worried takes an even greater toll.’

In addition to slowly introducing foods, Williams will likely need to start exercising slowly and with basic movements like itting and standing to regain her balance and reduce the risk of fractures. 

Dr Jaquish said: ‘She’s a very thin boned person. She may have to take longer because they want to avoid a fragility fracture because she’ll have low bone density.’

However, while the process will be grueling, he is confident both astronauts ‘can make a full recovery’ and will likely be able to return to space.

Dr Jaquish said: ‘There’s nothing permanent about what they’ve done, but they have to be very targeted about what they’re doing from an exercise and nutritional standpoint to get back there.’