I recall that in some movie (K-19?) after the reactor failure the sub doctor prescrived more red wine for the crew. That had me puzzled so I did some research.
I´m not certain about it, but one of the isotopes likely to be released is strontium 90, which is absorved in the bones because it´s chemically similar to calcium. So you end up with nuked bones cooking you up from the inside. Not good at all.
Wine, and apparently red in particular, contains strontium 85, non radioactive, so if you load up on booze you saturate the ammount of strontium you can absorb with the good stuff and thus the bad isotope just passes through without attaching to the bones.
At least that´s what I could piece together on my own. How effective it actually is in preventing radiation poisoning I have no idea.
Something similar is done with Iodine; it tends to accumulate on the thyroid gland in the neck, and a harmful isotope of iodine is generated by nuclear fission so in case of disaster one of the measures is to plop some iodine tablets to prevent the uptake of the radioactive isotope.