A list of the top 20 cancer beating foods – fruits and vegetables – has been compiled by the World Cancer Research Fund (WCRF).
The WCRF, a charity committed to cancer prevention, is publishing its findings in a report, Food Nutrition and the Prevention of Cancer, based on thousands of studies, being published in 2006. Eating more vegetables and fruit is the second most effective way to reduce the risk of cancer and the most effective way is not to smoke.
More than half the people questioned in a survey said they were unaware that diet could influence their risk of cancer
The 20 superfoods the WCRF identifies are vegetables, fruits, nuts, oily fish and whole grains – the familiar foods that it says “stand out in the nutritional crowd” because of their health-giving properties. They contain the highest levels of antioxidants, the vitamins and minerals that help protect the body from the damaging effects of oxygen-free radicals, the unstable molecules created by the body and produced by toxins that can be carcinogenic, such as tobacco.
Separately, the Royal Marsden Hospital in London is entering the fray with a book to be published next year called Cancer: The Power of Food.
This is the first time that the premier cancer-healing institution in Britain has offered advice to the public on cancer prevention, and the first time it has tried to cash in on the cookery book market.
Written by the hospital’s chief dietitian, Clare Shaw, the book contains recipes for dishes such as One-Pot Beef, with tips on the need to cook the beef slowly to “avoid the formation of heterocyclic aromatic amines”.
Cheesy Lentil and Vegetable Pie is a “high-fibre supper dish that is a good source of caretonids, folate and calcium”.
There’s useful advice on weight-loss regimes. Coyly avoiding any mention of the Atkins diet, the book asks whether a “high-protein, low-carbohydrate weight-reducing diet” will affect cancer risk.
“Yes, it might,” it says. “All the evidence for diet being protective indicates that it should contain plenty of starchy foods, fruit and vegetables, with small portions of animal protein.”
There are other valuable nuggets. Although it is assumed that raw fruit and veg are better than cooked, as some vitamins are destroyed in cooking, this isn’t necessarily true. The body absorbs beta carotene (which is converted in the body into Vitamin A) better from cooked carrots than raw.
Both the WCRF and the Royal Marsden try, in different ways, to refine the research evidence into advice that people can act on. Certain facts are established – such as the dramatic decline in stomach cancer in the west in the past century, thought to be linked with the advent of the fridge.
Refrigeration meant a switch in the diet to consumption of more fresh food and less preserved – salted or smoked – meat, which is known to increase the risk.
Stomach cancer remains high in countries where salty foods occupy a prominent place in the diet, such as Japan.
Bowel cancer is commoner in countries of the west, where more refined, processed food is eaten, and rare in the developing world, where the diet is high in whole-grain cereals, pulses and root vegetables. A high-fat diet also appears to increase cancers of the bowel, breast, prostate and lung.
But there is one problem with their thesis that has arisen too late for either organisation to address. The single most consistent piece of advice from the cancer epidemiologists in the past decade has been to eat more fruit and vegetables.
Southern Europe, where more fruit and vegetables are consumed, has lower rates of cancer of the mouth, throat, lung and stomach than northern Europe.
But what should we eat today? Those who have to cook tonight cannot wait for tomorrow’s research.
The only sensible answer is that a diet based on the WCRF’s 20 superfoods and the Royal Marsden’s recipes is unlikely to do harm, and probably offers the current generation the best chance of outliving their parents.