Testing the Effect of the Broccoli Seed and Sprout Extract, Avmacol ES, on the Cancer Causing Substances of Tobacco in Heavy Smokers

This phase II trial tests whether broccoli seed and sprout extract works to break down cancer causing substances of tobacco in heavy smokers. Smokers are at increased risk for developing lung, head and neck, and other cancers. Broccoli seed and sprout extract may help break down and remove toxic substances caused by tobacco use and possibly produce substances that may protect cells from tobacco smoke-induced damage in current smokers.