Anti-Neocons

I've always heard green tea was the best for our health because of all the anti-oxidants. Of course, some claims are quite outrageous like those who claim drinking green tea will prevent cancer. It will help fight off free radicals which are what causes cancer but it won't necessarily prevent cancer, only lower the risk. Another drink that I've read about recently is colloidal silver. Does anyone know what it does for one's health?