Here is a lot more what you can do to protect yourself (incl. links to scientific studies):
Taking supplements may be helpful, but if you still have access to organic and uncontaminated vegetables & fruits, then changing your diet (slowly!) to a raw food diet (vegetables, fruits, nuts and (sprouted) seeds, honey) will be the best protection from radiation and cancer (and all other kinds of diseases).
I higly recommend to drink about gallon of steam-distilled water every day.
This will flush out all the garbage (incl. radioactive particles) from your system:
Distilled water will only leach inorganic minerals (= toxic garbage) from your body (and not the organic minerals).
– What You Should Be Doing NOW to Protect Yourself from Radiation (Washington’s Blog, Nov 10, 2013)