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Men may be able to halve their risk of aggressive prostate cancer by adding large amounts of broccoli and cauliflower to their menu.
In a study of nearly 30,000 men, Dr Richard B. Hayes of the National Cancer Institute in Bethesda, Maryland, and colleagues found men who ate more than a serving of either vegetable each week had roughly half the risk of developing advanced-stage prostate cancer - that had spread beyond the prostate gland - compared with their peers who ate these vegetables less than once a month.
A number of studies have linked high fruit and vegetable diets with lower prostate cancer risk, but these results have been mixed. Few investigators have looked at advanced disease, Dr Hayes and his team note in the Journal of the National Cancer Institute.
The team looked at 29,361 men who were being followed as part of the Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial.
During more than four years of follow-up, 1338 of the men developed prostate cancer. Although there was no overall link between fruit and vegetable intake and prostate cancer risk, men who ate the most veggies had a 49 per cent lower risk of being diagnosed with prostate cancer that had advanced to stage III or IV (on a scale of I to IV), the researchers found.
Most of the effect appeared to be due to cruciferous vegetables, which include brussels sprouts, cabbage, broccoli and cauliflower; larger amounts of any vegetables in this family cut risk by 40 per cent.
Broccoli and cauliflower appeared to have the biggest impact.
Men who ate broccoli more than once a week had a 45 per cent lower risk of advanced prostate cancer than those who ate the vegetable less than once a month, while eating cauliflower often cut the risk by 52 per cent.
There was also a tendency toward reduced risk of aggressive disease among men who ate raw or cooked spinach at least twice weekly, compared with those who ate the vegetable less than once a month.
Cruciferous vegetables are rich in glucosinolates, the researchers noted, which can produce other chemicals with anti-carcinogenic effects.
The vegetables also are powerful antioxidants.
- Reuters
