It sort of reek unsound doesent it? Like CRISPR-CAS in moderation is possibly good for you.

Remember that one time where the that massage felt like being kicked by a boxer in the back? The assumption for low-radiation beeing healthy goes like this:

We are creatures of a naturally radioactive environment. Actually the environment was much more radioactive in the ancient past - which is why we search living and deceased fossils for DNA-Repair mechanisms, as these creatures would have to be much more cancer resistant back then. But i digress...

DNA-Digression, that is what radiation inflicts - also known as damage. Now this is super obvious damage kicking alive the repair mechanism, which also fixes alot of other - not so obvious damages or kills the cell.