Fruit and vegetables and cancer risk

• Published in: British journal of cancer Vol. 104; no. 1; pp. 6 - 11
• Main Author: Key, T J
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 04-01-2011; Nature Publishing Group
• Subjects: 692/499; 692/699/67; Alcohol; Biological and medical sciences; Biomedical and Life Sciences; Biomedicine; Cancer Research; Diet; Drug Resistance; Epidemiology; Esophageal cancer; Fruit; Fruits; Gastroenterology. Liver. Pancreas. Abdomen; Humans; Hypotheses; Larynx; Lung cancer; Medical research; Medical sciences; mini-review; Minireview; Molecular Medicine; Neoplasms - prevention & control; Oncology; Prostate; Risk Factors; Smoking; Stomach. Duodenum. Small intestine. Colon. Rectum. Anus; Tobacco; Tumors; Vegetables; lung cancer; breast cancer; colorectal cancer; vegetables; fruit; Lung disease; Rectal disease; Breast disease; Vegetables; Fruit; Nutrition; Respiratory disease; Lung cancer; Colorectal cancer; Breast cancer; Malignant tumor; Feeding; Colonic disease; Mammary gland diseases; Cancerology; Diet; Risk factor; Digestive diseases; Intestinal disease; Bronchus disease; Cancer
• ISSN: 0007-0920; 1532-1827
• DOI: 10.1038/sj.bjc.6606032

The possibility that fruit and vegetables may help to reduce the risk of cancer has been studied for over 30 years, but no protective effects have been firmly established. For cancers of the upper gastrointestinal tract, epidemiological studies have generally observed that people with a relatively high intake of fruit and vegetables have a moderately reduced risk, but these observations must be interpreted cautiously because of potential confounding by smoking and alcohol. For lung cancer, recent large prospective analyses with detailed adjustment for smoking have not shown a convincing association between fruit and vegetable intake and reduced risk. For other common cancers, including colorectal, breast and prostate cancer, epidemiological studies suggest little or no association between total fruit and vegetable consumption and risk. It is still possible that there are benefits to be identified: there could be benefits in populations with low average intakes of fruit and vegetables, such that those eating moderate amounts have a lower cancer risk than those eating very low amounts, and there could also be effects of particular nutrients in certain fruits and vegetables, as fruit and vegetables have very varied composition. Nutritional principles indicate that healthy diets should include at least moderate amounts of fruit and vegetables, but the available data suggest that general increases in fruit and vegetable intake would not have much effect on cancer rates, at least in well-nourished populations. Current advice in relation to diet and cancer should include the recommendation to consume adequate amounts of fruit and vegetables, but should put most emphasis on the well-established adverse effects of obesity and high alcohol intakes.