If we pay more and more attention in the everyday life to the role of food in terms of well-being, the link between food and the onset of cancer is an inexhaustible source of questions, often with claims to definitive answers on everything. Since there is a relationship between diet and cardiovascular diseases or cancers and that proper nutrition can prevent at least 30% of cancers, it is good, however, to take away easy illusions about miraculous foods, because a proper diet must, in any case, be included in a lifestyle that contemplates physical activity and abolishes factors such as smoking. In any case, it should be pointed out that there are no foods that are absolutely good or bad. Below is a review of some of the foods most affected by the clichés. We talked about it with Dr. Giovanna Masci, oncologist at Humanitas.
Diet and cancer, a few false myths to dispel
There are recent studies that have classified the red meat as probably carcinogenic and the processed meat as definitely carcinogenic, actually without indicating the degree of risk. However, the point is not to decide on the purification of the meat, but rather to reflect on the quantity that should be consumed, and preferably below three portions per week for red meat. It is also advisable to pay attention to cooking methods: steam and ovens are preferable to grills which, on the basis of some data, suggest a greater risk of cancer.
Seen as a health-promoting food, there is no irrefutable evidence to confirm its anti-cancer role. It is necessary to pay attention, especially for women of childbearing age and children up to 10 years of age, to mercury pollution, especially for large species (swordfish and tuna).
The alleged link between milk and dairy products and increased cancer risk is based mainly on the content of saturated fat and calcium in these foods. In fact, a higher risk for prostate cancer occurs for those who consume very high amounts of dairy products, while the same would have a protective effect against colorectal cancer. No health risk, therefore, if the consumption remains normal.
Fruits and vegetables
There is evidence and counter-evidence: if there are several studies that speak of their anti-cancer effect thanks to the fibers and active substances such as vitamins and antioxidants, it has been observed that people who follow poor diets of these foods are those most exposed to the risk of developing various types of cancer.
Sugar and sweeteners
There is no evidence of a direct correlation between sugar consumption and increased cancer risk, but there is a relationship, albeit indirect: excessive sugar consumption leads to an increase in body weight, in some cases even obesity which is a risk factor for over a dozen cancers (esophagus, breast, liver, stomach, kidney, pancreas, colorectal, bladder and uterus).
The body needs salt, but a too salty diet also damages the kidneys and bones, increasing the risk of osteoporosis, and also opens the way to stomach cancer.
There is evidence that the consumption of alcoholic beverages causes various cancers from the liver to those of the mouth, larynx, pharynx, esophagus, colorectal and breast for post-menopausal women. In detail, the WHO recalls that alcohol abuse causes 26 percent of oral cancers, 11 percent of colorectal cancers and 7 percent of breast cancers. Experts also point out that there are no differences in risk related to the type of alcoholic beverage, since what damages the cells is the amount of ethanol in these contents.
Researchers recommend that dietary supplements should not be used to prevent cancer. From an oncological point of view, the data show that high doses of beta-carotene supplements are associated with an increased risk of lung cancer in smokers, while calcium and multivitamin supplements may play a protective role against colorectal cancer. If, according to the experts, there are cases in which the use of supplements is justified: for example, vitamin B12 for people over the age of 50 who have difficulty absorbing the vitamin from natural sources or iron and folic acid for women who want to conceive or who are pregnant, the important thing is not to take supplements and lightly, but to rely on advice and prescriptions from specialists after appropriate analysis.
The word of Humanitas
“For a healthy and balanced diet it is important to follow a varied diet, consisting of both animal and vegetable products, without exceeding the doses, to avoid an excess of caloric intake – commented Dr. Masci -. In addition, it is recommended to take products that are not very elaborate and fresh, without the addition of additives and colorants”.