We've had various discussions about radiation on here and I just wanted to throw out that LifeExtension makes a supplement which reportedly mitigates the negative effect of imaging. You can
find it here. They have a longer article about it in their last issue of their magazine. Who knows if it really works, damage is only presumed since it's nearly impossible to prove at such low doses. the ingredients should be safe and it's not too expensive. I checked my CBCTs and they're in the range of 100-200uSv or about 20 days worth of background radiation, which isn't much, but wanted to throw it out there anyway for general knowledge.