Want to know what to do to fight cancer? Then eat those veggies, especially broccoli and cauliflower, said a doctor speaking at the American Institute for Cancer Research on diet and nutrition.

Paul Talalay, MD, from Johns Hopkins University in Baltimore, Md., said that cauliflower and broccoli contain a compound that increases an enzyme called sulforaphane in the body. This enzyme helps protect cells and prevents their genes from turning into cancer.

Even though the former American Cancer Society research professor has been looking at diet and cancer for more than 20 years, only now has Talalay found that eating foods like broccoli and cauliflower cuts the risk of bladder cancer.

Also, he learned that if a mouse does not have the gene that "turns on" these enzymes, the mouse will have more tumors than a mouse with the gene. This shows how key these enzymes are in helping to prevent cancer.

Talalay also said that it is better to grow your broccoli at home. It has more of the enzymes than the broccoli you buy in the store. Broccoli sprouts also are better for you than full-grown broccoli, and contain more of the enzyme.