Hello Agnese,
An excellent question... that is, I believe a slight, but real concern. There is however many ways to overcome these harmful effects with the appliance of science as used in our space stations, rockets and interplanetary vehicles. Our ancestors in documented ancient historical accounts around the world had to retreat to megalithic underground cites, with notable examples still to be in Turkey, West Asia. There are more to be found on every continent and many islands around the globe.
Read more about those incredible sites here
Following you now also :D