Question: What is the impact of travelling in space on the human body? How can we reduce the impact?

Beth Healey answered on 13 Oct 2015:

Hello, 934trn27! This is Adrianos from Greece, I am Beth’s predecessor as a research doctor for the European Space Agency in Antarctica and I am filling in for her today due to connectivity problems over there.

Our bodies face a series of challenges in space: We have evolved to live on the surface of the Earth, so the lack of gravity in space affects us in many ways: Our immune system gets weaker and we get sick more easily. The blood in our body, which is normally distributed evenly from head to toes, tends to accumulate in the upper part of our body, as there is no gravity to “pull it downwards”! Our bones become less dense as well. Last but not least, there is always a risk of being exposed to higher levels of radiation (from the sun or from the universe) when you are in space, because there is no atmosphere above you to filter the harmful rays.

Now what could we do for all that? Should we abandon space exploration? Far from it! What we try to achieve is provide the astronauts with effective “countermeasures”. For example, intense physical training in space can help reduce the loss of bone density. We can use medication to battle the effects of radiation or build a special “shelter” in the spaceship for astronauts to use in case of a radiation wave heading their way. The good thing is that our bodies tend to adapt to change, so for example, blood gets re-distributed again in a more even way across our body after staying a few days in space, the body “learns to adapt”. What we need to do is assist it and plan ahead!