This is the most definitive review of the science to date [as of 2007], and the most authoritative basis for action to prevent cancer worldwide. It is co-published by World Cancer Research Fund and American Institute for Cancer Research. These are the recommendations based on expert judgements of systematic reviews of the world literature. This is the result of a five-year examination by a panel of the world’s leading scientists. This is from the Second Expert Report of the Food, Nutrition, Physical Activity, and the Prevention of Cancer: a Global Perspective.
- Eat plant foods: Eat mostly foods of plant origin. Eat at least five portions/servings (at least 400 g or 14 oz) of a variety of non-starchy vegetables and of fruits every day. Eat relatively unprocessed cereals (grains) and/or pulses (legumes) with every meal. Limit refined starchy foods. People who consume starchy roots or tubers as staples also are to ensure intake of sufficient non-starchy vegetables, fruits, and pulses (legumes).
- Limit animal foods: Limit intake of red meat and avoid processed meat. People who eat red meat are to consume less than 500 g (18 oz) a week, very little if any to be processed.
- Limit foods and drink that promote weight gain: Limit consumption of energy-dense foods. Avoid sugary drinks. Consume energy-dense foods sparingly. Consume fast foods sparingly, if at all.
- Avoid body fatness: Be as lean as possible within the normal range of body weight. Ensure that body weight through childhood and adolescent growth projects towards the lower end of the normal BMI range at age 21. Maintain body weight within the normal range from age 21. Avoid weight gain and increases in waist circumference throughout adulthood.
- Limit preservation, processing, preparation: Limit consumption of salt. Avoid mouldy cereals (grains) or pulses (legumes). Avoid salt-preserved, salted, or salty foods; preserve foods without using salt. Limit consumption of processed foods with added salt to ensure an intake of less than 6 g (2.4 g sodium) a day. Do not eat mouldy cereals (grains) or pulses (legumes).
- Breastfeed babies: Mothers to breastfeed; children to be breastfed. Aim to breastfeed infants exclusively up to six months and continue with complementary feeding thereafter.
- Be Physically active: Be physically active as part of everyday life. Be moderately physically active, equivalent to brisk walking, for at least 30 minutes every day. As fitness improves, aim for 60 minutes or more of moderate, or for 30 minutes or more of vigorous, physical activity every day. Limit sedentary habits such as watching television.
- Limit Alcoholic drinks: If alcoholic drinks are consumed, limit consumption to no more than two drinks a day for men and one drink a day for women.
- Avoid Dietary supplements: Aim to meet nutritional needs through diet alone. Dietary supplements are not recommended for cancer prevention.
- For Cancer survivors: Follow the recommendations for cancer prevention. All cancer survivors to receive nutritional care from an appropriately trained professional. If able to do so, and unless otherwise advised, aim to follow the recommendations for diet, healthy weight, and physical activity.
For a further explanation of the above, see the Summary, Food, Nutrition, Physical Activity, and the Prevention of Cancer: a Global Perspective. They have a great matrix table showing the strength of the evidence relating causation of 61 foods and lifestyle activities to 18 cancer types and obesity. For example, by looking at the column for pancreatic cancer, you can see that foods containing folate offer probable decreased risk, and body fatness has convincing increased risk. Also, you can see that alcoholic drinks are bad for 6 particular cancers.
This is from World Cancer Research Fund / American Institute for Cancer Research. Food, Nutrition, Physical Activity, and the Prevention of Cancer: a Global Perspective. Washington, DC: AICR, 2007