Frenzied Fluids

Space may sound glamorous, but living in space changes the way you look, and in space you should never stray too far from a bathroom. Gravity affects water and lymph, fluids found in our bodies. Lymph helps our bodies fight against sicknesses like the cold or flu and other infections.

A diagram showing fluid movement in the body.

On Earth, fluids are being pulled down by gravity, and our muscle movement helps to move them back up. In space, because body fluids aren’t pulled down by gravity, they collect around the chest and head.

The upper body swells, and astronauts get what’s called “puffy face.” Because fluids don’t move around the body as well as when on Earth, these pools of fluid fool the body, making it think it is carrying too much water. This makes the astronauts have to pee a lot. In space, astronauts pee more and drink less, so they can become dehydrated very easily.