Those who are still worried can protect themselves by increasing their intake of antioxidants. Foods such as fresh green vegtables, tea and coffe are all anti-oxidants. Fruit such as berries (the darker the skin - the better) also work well. Products from these are also efficeint in combating the free radicals produced by ionizing radiation which can cause DNA damage.
Personally, I follow the advice given by the Russian Navy. The reactors on the old Soviet submarines are so leaky, the submariners are given a ration of 250ml of red wine a day!
Another glass of protection anyone?