The physical appearance of UAE astronaut Sultan Al Neyadi has changed significantly since he arrived at the International Space Station three months ago.
Doctors in the UAE have said that Dr Al Neyadi is experiencing what is a common transition for astronauts in space.
The 42-year-old is experiencing what is also known as 'Moon face', a phenomenon caused by a shift in body fluids, leading to facial swelling.
The condition, which is not permanent, goes away once astronauts return to Earth, with gravity pulling fluids back down in the body.
Dr Sana Kausar, an aviation medical examiner at King’s College Hospital Dubai, told The National that weightlessness can take its toll on the human body.
“There is a change in the components of blood and cellular fluid. This also contributes to fluid shift,” she said.
“On Earth, gravity pulls fluid downwards and this can redistribute in space, causing ‘Moon face’ in astronauts.
“In the pictures, we can see that Sultan’s face is noticeably puffier.
“It looks like the ‘Moon face’ we see commonly in astronauts.”
She added that astronauts recover “once gravity kicks back in and affects the fluid redistribution.”
Dr Pavithra Reddy, a specialist in internal medicine at Prime Medical Centre, warned that other health issues can also develop from the swelling.
“Earth's gravity keeps the blood flow throughout the body in order, but in zero gravity, most of the blood and other fluids move up to the chest and facial areas,” she said.
“Therefore, areas of chest and face bloats up as you can in Sultan Al Neyadi's face.
“Due to the high fluid concentration in the facial area, stuffy nose, reduced sense of smell, cold and headaches are normal to occur.”
UAE's first astronaut also got 'a bigger head'
Hazza Al Mansouri, the first UAE citizen to fly to space in 2019, also noted a change in his physical appearance during his eight-day trip when his face swelled up only after two days on the ISS.
“Many changes have happened in my body,” Maj Al Mansouri said at the time, as reported by local media.
“The size of my head grew bigger because of the rush of fluids upwards, and my sense of smell also changed.”
Dr Kausar said that long-duration missions can cause the process of ageing to happen faster.
Maj Al Mansouri was on the ISS for a short stay, but Dr Al Neyadi is there for six months, which is considered a long-duration mission.
“On Earth, ageing affects the cardiovascular and other systems and these changes are seen 10-fold faster in space than on Earth,” Dr Kausar said.
“The human body is adapted to the gravity we have on Earth and would take time to adapt to longer-term exposure to weightlessness, but shorter-term exposure is usually recoverable.”
Nasa astronaut Scott Kelly spent a total of 520 days on the space station, with a consecutive 340 days in 2015 and 2016.
His health was compared with his twin brother on Earth.
It was found that Mr Kelly's eyesight, height and health were dramatically affected by zero gravity.
His heart shrank by 25 per cent, and after one year aboard the ISS, Nasa researchers found he had grown 5cm and was taller than his identical twin brother Mark, who is also an astronaut.
Exercising in space to keep healthy
Dr Al Neyadi has spoken about how astronauts are required to exercise for at least two hours daily to keep healthy.
Bone and muscle mass decreases the longer an astronaut stays in microgravity.
This is why space agencies make it mandatory for their astronauts to use the treadmill and other exercise equipment on the ISS daily.
