NEW YORK (Reuters Health) - Eating raw, but not cooked, cruciferous vegetables may help protect against the development of bladder cancer, according to research reported today during the Sixth Annual International Conference on Frontiers in Cancer Prevention, sponsored by the American Association for Cancer Research.
Cruciferous vegetables, such as broccoli and cabbage, "are chock full of isothiocyanates (ITCs), which are a well-known class of cancer prevention agents especially promising in bladder cancer chemoprevention," the researchers explain in their abstract.
But it's been unclear how much one needs to eat to reap the protective benefits or if cooking alters the chemoprotective punch of cruciferous vegetables.
Dr. Li Tang and colleagues from Roswell Park Cancer Institute in Buffalo, New York, collected detailed dietary information from 275 individuals diagnosed with primary bladder cancer and 825 individuals without cancer.
They found that eating three or more servings a month of raw, but not cooked, cruciferous vegetables, such as broccoli, cabbage and cauliflower, reduced the risk of bladder cancer by roughly 40 percent overall.
"Most importantly, smokers, even heavy smokers, may also benefit from eating raw cruciferous vegetables," Tang said. The risk reduction associated with eating at least three servings of raw vegetables per month for the smokers and heavy smokers was around 40 to 54 percent, Tang reported.
The reduction in bladder cancer risk was greatest -- 73 percent risk reduction -- among non-smokers eating three or more servings per month of raw cruciferous vegetables.
La réduction du risque du cancer de la vessie a été la plus grande -73% - parmi les non-fumeurs qui mangent 3 ou + portions de légumes crucifères crus par mois
"Cooking can substantially reduce or destroy ITCs in vegetables," Tang added, "which is why you need to eat raw cruciferous vegetables to receive the food's maximum benefit."