Piperine is the active component in pepper that is believed to prevent the harm that free radicals can cause your body. Piperine also has the ability to enhance the absorption of other beneficial anti-cancer compounds in other foods.
When black pepper is ingested alongside green tea, the absorption of the anti-cancer compound EGCG present in green tea is highly increased. Also, the body’s absorption of curcumin (the compound in turmeric) increases by 2000% when you add black pepper!
Read more about curcumin here.