Surprising body changes in zero-G space environment

In space, the absence of gravity causes various changes in the human body. Astronauts can grow taller as their spines elongate, but this can lead to back pain. The heart becomes smaller and changes shape due to easier blood flow. Bones lose calcium and become brittle, necessitating exercise to maintain bone density. Vision can be affected by changes in intracranial pressure, requiring different glasses prescriptions. Despite these challenges, the exploration of space is considered worthwhile.

What are some of the physical changes that occur to the spine in space?

Describe how vision can be affected by being in space.