Do fruit and vegetables prevent cancer?

Posted by Josette Dunn on 7th April 2010

Many people believe that eating well, particularly eating more fruit and vegetables can reduce their risk of cancer, or even help to cure it.  A new study in the Journal of the National Cancer Institute has looked at whether or not fruit and vegetables really are protective against cancers. The study found only a “weakly protective effect” against cancer.

 According to the Cancer Council Australia, fruit and vegetables are high in nutrients that are potentially protective against cancer. They also play an important role in weight management.

Because obesity is a convincing risk factor for cancer of the colorectum, kidney, pancreas, oesophagus, endometrium and breast (in post-menopausal women), the Cancer Council advises that fruit and vegetables may also protect against cancer indirectly by helping to maintain a healthy body weight.

Although there has been a slight weakening of the evidence supporting the role of fruit and vegetables in reducing the risk of some cancers, overall the evidence is suggestive of a protective effect. Fruit and vegetables appear to protect against cancers of the digestive tract, such as cancer of the mouth, pharynx, larynx, oesophagus, stomach and colorectum. Fruit may also protect against lung cancer.

The recent study in the Journal of the National Cancer Institute found that eating more fruit and vegetables had a similar association with reduced cancer risk, as eating more vegetables only. Increased intake of fruit only, showed a weaker association with reduced cancer risk. 

Results also suggested a stronger reduction in cancer risk in heavy drinkers who increased their fruit and/or vegetable intake, than in non-heavy drinkers,  and was confined to cancers caused by smoking and alcohol.