Micro-gravity will have an adverse effect on muscles and bones, and muscle strength could decline by up to 30% and bone mass by 1-2% a month.

Spinal elongation also makes astronauts taller and they also experience back pain and spine problems after their return to Earth.

Weight loss may be possible, as seen in the case famously experienced by astronaut Scott Kelly who reduced his body weight by 7%

Eyes and vision gets altered by fluid shifts in space travel and sadly, these conditions are generally irreversible.

Neural connections can be rewired in the brain leading to alterations in the motor skills as well as spatial orientation.

NASA was quite impressed by the effects of space travel on gut bacteria, which is a change resulting from diet, environment, and radiation.

Cosmonauts can develop symptoms of increased skin supersensitivity and rash after their travel to space

Long duration spaceflight alters Telomere length and causes DNA damage with subsequent health implications.