To stymie cancer, eat broccoli raw.

To stymie cancer, eat broccoli raw

Several studies have linked a reduction in cancer risk with diets featuring lots of vegetables from the Brassica genus -- such as cabbage, broccoli, cauliflower and brussels sprouts. But whether one eats them raw or cooked could make a big difference, suggest Lloyd D. Campbell and Bogdan A. Slominski of the University of Manitoba in Winnipeg.

Brassica vegetables contain relatively high levels of compounds called indole glycosinolates (IG). In animal studies by others, IG derivatives--including several that form when these vegetables are cut or heated -- not only prevented mammary tumors and precancerous forestomach lesions but also increased the activity of several key detoxifying enzymes. These beneficial compounds vary in potency, however. And which predominates in any given Brassica depends on how the veggie is prepared, the Canadian team reports in the September/October JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY.

The IG derivatives that predominated in cut or mashed raw vegetables were those that had proved the most potent tumor inhibitors in animals, the pair discovered. Moreover, they found that roughly half the IG derivatives that did form in boiled Brassicas escaped into the cooling water, never making it to the plate. The researchers conclude that Brassicas' role in preventing stomach and colon cancers "should be attributed primarily to the consumption of raw vegetables."