Can cauliflower prevent prostate cancer? A prospective study of 29,361 men showed that those who ate cauliflower more than once a week were 52% less likely to develop aggressive prostate cancer than those who ate cauliflower less than a month. Broccoli was almost as protective as cauliflower, reducing the risk of prostate cancer by 47%. Cabbage, Brussels sprouts and turnips were also found to be protective.
Source: http://jnci.oxfordjournals.org/content/99/15/1200.short