"The primary benefit of soy comes from its isoflavone content. Isoflavones are antioxidants that combat damage caused by free radicals. In one study soy isoflavones reduced total cholesterol over 9% and LDL (bad) cholesterol almost 13%. The level of HDL (good) cholesterol increased over 2%. If you are battling high cholesterol, soy isoflavone may provide necessary support to lower cholesterol.