Introduction to Cancer Prevention

The distribution of the different types of cancer is not the same in all countries. This indicates that in the onset of cancer there is environmental factors. More than 90% of cancers in industrialized countries can be attributed to lifestyle, such as smoking and diet, and to environmental influences, such as environmental pollutants. About a third (or slightly less) of cancers are related directly with food.

In some specific cases of cancer it is known that there is clearly a genetic effect or a genetic predisposition. But, even in these cases, in its appearance.

Therefore, changes in our eating pattern will also play a very important role in cancer prevention.

And, on the other hand, diet is also a key point once cancer has been detected. Correcting the poor nutritional status caused by the disease or caused by the treatments against it will have a decisive influence on the final response to the disease. treatment and healing.

What do we know about cancer

By the term cancer we mean a abnormal mass of tissue characterized by uncontrolled cell growth that compose it, and that as it grows it expands locally and remotely, causing the death of the individual who suffers from it. The growth of cancerous tissue is autonomous and competes with normal tissue for energy supplies and nutritional substrates.

cancer is born from a single cell, which has "transformed" and is then capable of grow and multiply endless until giving a more or less large mass, which is what we detect. At the origin of this transformation is the appearance of defects in the genetic material of the cell that are sometimes known and sometimes not.

Some viruses, ionizing radiation and certain chemical substances are the three main groups of agents with the potential to transform a normal cell into a cancer cell; are known as substances carcinogenic or carcinogenic. In the diet, the presence of chemical carcinogens that are cause of cancer.

The carcinogens Chemicals found in food work by damaging the genes of the cell and "turning" it into a cancer cell by a generally indirect mechanism. This means that carcinogens (better to call them procarcinogens) require the change of their structure within our body; Thus new substances are formed, which are the final carcinogens (proper carcinogens). It should be considered that, although different agents are considered separately in this text, many of them can act as a team and potentiate the effects of other carcinogens.

cancer and diet

To produce cancer, not only the presence of the carcinogen in the body is necessary. There must be other circumstances, such as the presence of high enough doses carcinogen in the body, the presence of substances (called promoters) that help the carcinogen make its cell damage and as this damage progresses, the ability to regenerate the damage produced by the damaged cells themselves and cells of the immune system (lymphocytes), and the presence or absence of anticarcinogenic substances that can also come from food. To this we must add the genetic predisposition of the individual.

Promoters are usually hormones that we manufacture ourselves, for example androgens and estrogens, or as herbicides or certain drugs such as phenobarbital; But there are also promoters in the foods we eat, for example phorbol esters (from herbal teas) or safrole (from saffron and black pepper). Promoters do not have the potential to cause cancer on their own.

In summary, there are three aspects of diet that we must consider due to their relationship with cancer and which will be discussed in other chapters:

Carcinogens and anticarcinogens may or may not be nutrients, as they are sometimes present in food but lack nutritional value.

Carcinogenic substances

Some carcinogens are formed during food handling, either for conservation or during cooking. This is the case of meat and fish that have been prepared grilled or smoked and that contain polycyclic aromatic hydrocarbons such as benzopyrene, which is also present in roasted coffee. Nitrosamines are other carcinogens that appear by reaction between food amines and nitrites that are used as food additives.

Polycyclic aromatic hydrocarbons, in addition to being present in foods that have been grilled or smoked, are also present in foods that have been grown in areas with high levels due to the combustion of petroleum or coal derivatives.

Carcinogens can also be substances produced by industrial activity, such as artificial sweeteners, or nitrites that are used as food additives.

Others are simply substances that are incorporated into food through air or water or microorganisms that can grow in them. This is the case of aflatoxin B1, produced by fungi that grow in storage places for corn, peanuts, etc.

Finally, some carcinogens are natural products, which are naturally in food. Some examples are: alcohol; methylxanthines (caffeine, theobromine) from coffee, tea, cola and cocoa; the phorbol esters found in herbal teas; nitrates from spinach; hydrazines from mushrooms; safrole in saffron and black pepper; and potato alkaloids.

Anticarcinogenic substances

In the diet we also find anticarcinogenic substances, which are of vital importance in the prevention of cancer. The abundant intake of fruits and vegetables or foods with has a protective effect against cancer. They correspond, in general, to foods rich in antioxidant vitamins, in other antioxidants, in certain minerals and in fiber. These include folic acid, vitamin C, vitamin E, ß-carotenes and selenium. However, it has been observed that this protective effect demonstrated by food disappears when the isolated nutrient is provided (vitamin C, for example, as a supplement in pill form) and may even be responsible for undesirable adverse effects such as increasing the incidence of cancer.

In conclusion…

In summary, we must not panic. It is true that substances with carcinogenic potential have been described in the food we eat: nitrates from spinach, hydrazines from mushrooms, alkaloids in potatoes ... but none of them pose a risk when there is a moderate consumption of these foods and if the diet is varied. Thus, we must be in favor of a balanced and healthy diet, in which the foods are varied, are in moderate quantities, where the fruits and vegetables, whole grains, and legumes play an important role, where reduce intake of animal fats, smoked and salted, and where all this is accompanied by physical activity, smoking is eliminated, alcohol is reduced, and obesity and overweight are reduced. Internal Medicine specialist

Deborah Blasco Nutritional Nurse Specialist