Diet versus cancer – does it work?

Can we avoid cancer by drinking green tea, eating beans, and using olive oil for everything? By following the dietary recommendations, will we be sure that we will never get sick? Some try to convince us that it is so. How much truth is there?

A professor of medicine once said, “I would like to live to be ninety and die from the bullet of a jealous spouse whom I have just eaten the horns of.” A beautiful vision. Each of us would like to live a long and healthy life, and then go away with gusto. However, will adherence to the four basic principles of lifestyle – eat healthy, be active, do not abuse alcohol and do not smoke – ensure our longevity and protect against possible cancers?

In the introduction to the report of the International Agency for Research on Cancer, WHO Director-General wrote that up to 80% of cancer cases may be caused by external factors, such as lifestyle and the environment. Research conducted by various centers and institutions confirms that a healthy diet can extend life – in the optimistic variant by up to 20 years, and in the more pessimistic one – by about 5 years. However, the more skeptical among scientists emphasize that this relationship is not so clearly defined.

Complicated dependencies

Food items are difficult to put into two tables: “Promote cancer” and “Prevent cancer.” – A diet to prevent cancer is very controversial. Much research is still ongoing and scientists have so far found little to be conclusive. The results so far are often contradictory – notes the drug. med. Katarzyna Bukol-Krawczyk, internist and nutritionist at the ENEL-MED Medical Center. Besides, what is probably the most important: it is impossible to assure people that by eating foods considered healthy, for example vegetables, fruit, fish, vegetable oils or foods rich in fiber, they will certainly avoid getting cancer. You can reduce the probability of a certain type of occurrence to some extent. And that is not guaranteed either. Cancer is a matter of complex processes that take place in the human body. – The problem is really complex. There are many risk factors. There is no certainty that by eating healthy you will not get cancer. After all, a cancer independent of the diet may attack us – says Katarzyna Bukol-Krawczyk.

Diet-dependent cancers include those that directly affect the gastrointestinal tract, ranging from the mouth, throat, esophagus, through the stomach, liver to colon, but also breast, prostate and lung cancer. For a change, the influence of diet is difficult to find in the genesis of melanoma. Brain tumors also have little to do with diet. But on the other hand, we must know that poor nutrition weakens the body’s natural defenses, and this already has a significant impact on the occurrence of diseases, including cancer. Following this lead, it can be concluded that each cancer depends to some extent on diet – concludes the doctor.

Simply put, it looks like this. We all carry cancer cells within us. Whether we let them grow or not depends on the state of our immune system. When it works properly, it is able to defend us against the enemy, which is cancer, but when it fails, it hardly recognizes cancer cells, which then make it much easier to “break out” from surveillance. Therefore, we act to our own disadvantage each time we provide the body with “fuel” in the form of large amounts of saturated fat, sugars and highly processed food, which is not a source of substances necessary for the proper functioning of the body. In addition, it is known that overweight people live shorter lives. Research shows that even if they do not develop obesity-related diseases, such as cardiovascular disease, it will most likely be cancer.

Toxic compounds residing in the body have the most significant influence on the occurrence of cancer, especially in the gastrointestinal tract. The longer they stay there, the greater their harmful effect. – That is why it is so important to eliminate them from the diet and remove them from the body as soon as possible – says the dietitian.

Uneasy research, uncertain conclusions

There is a wealth of research into the effects of diet and individual foods on cancer incidence. Although they have been conducted for quite a long time (the first took place in the 40s), not all of them clearly define the relationship between what we eat and the occurrence of cancer. Diet affects health, but it is difficult to clearly determine whether, for example, vegetables reduce this risk in each case, or only in certain types of cancer. Or maybe we overestimate their operation at all. For methodological reasons, obtaining 100% certain results is rather impossible.

On the other hand, one of the most reliable studies is the EPIC (European Prospective Investigation into Cancer and Nutrition) study. They were conducted for 10 years in most Western European countries on a group of 0,5 million people. It consisted in sending surveys to selected people regarding lifestyle, and above all, the diet. – Due to the size of the sample and the duration of the study, I believe that this is one of the most reliable studies on cancer prevention. Importantly, no pharmaceutical company took part in it – emphasizes Katarzyna Bukol-Krawczyk.

What helps and what harms?

What are the conclusions of the conducted research? In short: the fiber contained in whole grain cereal products reduces the risk of cancer of the gastrointestinal tract, especially of the colon (accelerates the removal of toxins). Vegetables and fruits have a similar effect on the digestive system, but its upper part. Active substances contained in them, incl. antioxidants work until they reach the stomach. In the further sections of the digestive tract, only fiber has a beneficial function. In the case of breast or prostate cancer, no relationship related to the consumption of vegetables or fruits was found. This is quite a subversive statement given the tremendous anti-cancer importance attributed to them.

What else is anti-cancer? Fish, and more precisely the omega-3 fatty acids contained in them. They reduce the risk of colon cancer, but also – most likely – lung, breast and prostate cancer. Other studies have confirmed this, concluding that eating fish at least twice a week significantly reduces the risk of cancer. The most omega-3 fatty acids can be found in tuna, mackerel, sardines and salmon. They are also found in linseed or fish oil, which has been known for a long time to increase immunity and thus constitute an effective barrier against cancer cells. However, there is a lot of discrepancy in milk and its products. The EPIC study showed that they have a strong preventive effect, mainly in the prevention of colon cancer. It is not known, however, whether it is related to the calcium present in it or CLA acid.

What is the harm? There is undoubtedly a different type of fat, saturated, especially trans fat, which we find in highly processed foods, as well as in margarines. They promote obesity and inflammation. The black list also includes alcohol (the toxic metabolites it contains have a significant effect on the gastrointestinal tract – from the esophagus to the large intestine), salt, red meat (increases the risk of stomach and colon cancer, as well as breast cancer). Research is also underway on the effects of sugar and white flour on the formation of cancer cells. Dr. David Servan-Schreiber, author of the book “Anti-Trauma”, is convinced of their disastrous action. When sugars are consumed, insulin is bursting, fueling inflammatory processes that stimulate cell growth and serve as fuel for tumors. American research confirms that excessive consumption of products with a high glycemic index promotes cancer, including breast and prostate, and is also associated with cancer of the pancreas, colon and ovaries.

Food combinations

The main problem with the anti-cancer diet is that: it is very easy to attribute beneficial effects to certain products (however, you need to have evidence for this) and it is difficult to guarantee their effectiveness. “I am against telling people that they will keep themselves healthy by eating garlic.” In my opinion, if we want to avoid cancer, we should follow the general recommendations: introduce as few toxins into the body as possible, avoid pesticides (wash vegetables, fruits), highly processed foods, buy products from proven sources, drink plenty of water (this is also a method of excretion) , provide fiber (accelerates intestinal transit) and antioxidants that destroy free radicals. It is recommended to consume 5 servings of 80 g of vegetables and fruit a day, limit alcohol (not eliminate it) and follow the guidelines contained in the current food pyramid (so-called Harvard) – recommends Katarzyna Bukol-Krawczyk.

Research also confirms that preventive actions cannot be limited to consuming one product. So let’s get rid of the illusions that one grapefruit a day or a cup of green tea will help us. Instead of catching up to press reports, not always confirmed, let’s try to provide the body with various products every day, which will systematically strengthen it.

Almost like a medicine:

1. green tea;
2. soy;
3. turmeric, curry;
4. ginger;
5. spices: mint, thyme, basil, marjoram, rosemary;
6. citrus;
7. Red wine;
8. grapes;
9. nuts, almonds;
10. peas, beans, lentils, sprouts;
11. cabbage;
12. tomatoes;
13. garlic, onion;
14. strawberries, raspberries, blueberries, cherries;
15. fish, olive oil;
16. dark chocolate;
17. celery;
18. vitamins A, C, E.

Reading for the inquisitive

More information on the principles of the anti-cancer diet can be found in the books: Anti-cancer by Dr. David Servan-Schreiber and The New Anti-cancer Diet by Dr. Johannes F. Coy and Maren Franz.