Tuesday Nov 18, 2008 (foodconsumer.org) -- Broccoli and other cruciferous vegetables may help protect against lung cancer in smokers, according to a new study presented at the American Association for Cancer Research’s Seventh Annual International Conference on Frontiers in Cancer Prevention Research.

Cruciferous vegetables have already been known to confer a protective effect against a number of cancers.   But this is the first study to report the benefits for smokers, according to lead author Li Tang, Ph.D., a post-doctoral fellow at Roswell Park Cancer Institute.

"Broccoli is not a therapeutic drug, but for smokers who believe they cannot quit nor do anything about their risk, this is something positive," Tang said. "People who quit smoking will definitely benefit more from intake of cruciferous vegetables."

The researchers found that the protective effect from cruciferous vegetables in smokers was a reduction of 20 t 55 percent in the risk of lung cancer depending on the type of vegetable consumed and the duration and intensity of smoking.

For current smokers, only consumption of raw cruciferous vegetables was correlated with risk reduction of lung cancer.   General vegetables and fruits were not associated with the risk.

The strongest risk reduction was found among patients with squamous or small-cell carcinoma, which are more strongly linked with heavy smoking.

"These findings are not strong enough to make a public health recommendation yet," said Li. "However, strong biological evidence supports this observation. These findings, along with others, indicate cruciferous vegetables may play a more important role in cancer prevention among people exposed to cigarette-smoking."

Cruciferous vegetables include kale, collard greens, cabbage, Brussels sprout, broccoli, cauliflower, Chinese cabbage, turnip, radish and watercress, according to Wikipedia.

Quitting smoking is the best way to prevent lung cancer, which is diagnosed in 215,020 men and women and kills 161,840 in 2008, according to the National Cancer Institute.