Does a vegetarian diet prevent cancer?

Bad news for those of you hoping to reduce their cancer risk by eating a diet rich in fruits and vegetables: it doesn't seem to work. The results of a decade-long epidemiologic study in the British Journal of Cancer (link) seem to suggest there is no protective effect between fruit and vegetable consumption and several of the most common cancers- such as lung, breast, colorectal or prostate cancer.

Initial studies in the 1990s appeared to show that those with a low intake of fruit and vegetables were at greater risk of developing cancer. More specific follow-up studies, however, have concluded that larger intakes of fruit and vegetables do not offer greater protection.

This study, from Oxford University, recommends that we should continue to include "at least a moderate amount of fruits and vegetables" based on basic nutritional principles, but that increasing this level would not have much effect on cancer rates. Instead, the study's author suggests that we need to really look at the adverse effects of obesity and high alcohol consumption rates.

However, my vegan friends need not despair: in a separate study, the incidence of coronary heart disease or stroke was 30% lower for those consuming five or more servings per day compared with those eating less than 1.5 servings of fruits and vegetables per day.

So once again, mom was right: an apple a day is a good thing. It just doesn't prevent cancer.