Choices we make with our children can strongly influence their odds of getting cancer for the rest of their lives. Food, Nutrition, Physical Activity, and the Prevention of Cancer: A Global Perspective, released in November 2007, is comprehensive analysis of over 7000 different scientific studies.
Based on these, the expert panel makes 8 core recommendations (and two special recommendations) for cancer prevention. Among other things, this is the first major report to recommend breastfeeding for preventing cancer in both mothers and their babies. The potential benefit from following all of these recommendations is huge (preventing as many as 1/3 of all cancers), but for many families they may feel overwhelming. Knowing the targets, though, may help to make some steps in the right direction. The report includes recommendations for all of us, but I will focus here on how their recommendations apply to children:
1) Get lean and stay lean. Aim for a body mass index (BMI) towards the lower end of the normal range throughout childhood and adolescence (and maintain this as an adult). This may be one of the most important ways to prevent cancer later in life. Excess fat increases levels of circulating hormones linked to cancer, and makes it more likely that cells undergo abnormal growth.
2) Get moving. Aim for 60 minutes or more of moderate activity, or 30 minutes or more of vigorous activity, every day. And limit sedentary habits such as watching television – especially where there is child-targeted marketing of junk food or sugary drinks.
3) Don’t think calories. Think calorie density. Calorie density is the number of calories per a certain weight of food (usually 100 grams). Watch out for calorie dense foods! Feed kids ‘fast foods’ sparingly, if at all. (By ‘fast foods’ they do not mean foods that are convenient, or ordered at chain restaurants, but foods that are high calorie density, eaten in large portions, and that easily become large parts of the diet — such as burgers, fried chicken pieces, French fries, shakes, or sodas. Avoid sugary drinks, and choose calorie-dense foods sparingly. Calorie-dense foods are those with 225 calories or more per 100 gm. The target is to have the diet average about 125 calories per 100 gm, with some foods lower and some foods higher than the average. Per 100 grams, fruits and vegetables usually have 10 to 100 calories; cereals and legumes between 60 and 150, and breads, lean meats, fish, and poultry between 100 and 225 calories.
4) Plant foods rock! — mostly. Kids should get at least 5 servings a day of fruits and non-starchy vegetables (more servings would be even more protective). Include whole grains or legumes at every meal (while limiting white rice or things made from white flour, such as bread, pasta, pizza, cakes, pastries, cookies or biscuits). Between the fruits and vegetables and the whole grains, most of the foods that children eat should be of plant origin.
5) Animal foods with caution. For those kids who do eat red meat, they should aim for less than 18 ounces a week. (Note: From my perspective, the issue with red meat is mostly the hormones found in conventional beef. Grass fed organic beef is far preferable.) Poultry or fish could be good options instead. It’s also best to minimize or avoid processed meats – especially those treated with nitrates, nitrites or other chemical preservatives. This would include many brands of ham, bacon, pastrami, salami, sausages, and hot dogs, as well as some hamburgers. The panel did not recommend reducing dairy, eggs, fish, or poultry for cancer prevention.
6) No alcohol for kids. Kids should not be exposed to alcohol, even before they are born. For cancer prevention, alcoholic drinks should be avoided entirely by children and by pregnant women. In addition, they recommend limiting alcoholic drinks to two per day for adult men, and one per day for non-pregnant adult women.
7) Manage molds and salt. Preservation, processing, and food preparation makes a difference. Limit salty foods, and processed foods with added salt. No one should get more than 2400 mg a day of sodium. (Kids shouldn’t get more than 1500 mg of sodium a day before age three, 1900 mg a day before age eight, or 2200 mg a day before age thirteen.) Don’t eat moldy foods made from grains or legumes, such as bread or peanut butter. Suspect hidden molds if these foods have been stored too long at room temperature.
8) Dietary Supplements. Aim to meet a child’s nutrition needs from real food. Except for Vitamin D supplements for exclusively breastfed babies, supplements have not been linked to cancer prevention in kids. (I recommend a multivitamin safety net for other purposes.)
Special Recommendation 1 – Breastfeeding. Aim to breastfeed exclusively for six months, and to continue breastfeeding as other foods are introduced. This has been shown to reduce the lifetime cancer risk for both the baby and for the mother.
Special Recommendation 2 – Cancer Survivors. The above core recommendations are all the more important for kids (and adults) who are cancer survivors. The report recommends that survivors receive the support of a trained nutrition professional to help them meet these goals for the future.
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