CANCER: BALANCED DIET AS BEST FORM OF PREVENTION

Q&A with Professor Attilio Giacosa
Head of Department of Gastroenterology, Policlinico di Monza, Italy
By Andrea Massa

Professor Giacosa, you are one of the most listened-to supporters of the preventive diet. What are the main pillars of this type of diet?
The first and very important pillar is the protective role of fruit and vegetables. This is an area for which we have the most consistent data. 

The success of prevention, therefore, starts from the plate, with fruit and greens holding extraordinary power. How do we know this?
Through epidemiological data and observations in population groups with cancer that were compared to age and sex matched groups without cancer. If we look at the diet and eating habits of both groups, case-control studies have irrefutably demonstrated a protective role of fruits and vegetables against many types of cancer in diverse social, environmental, geographic situations, especially for tumors of the lung, oral cavity, esophagus, stomach, and intestine.

Isolating the range of micronutrients from fruits and vegetables and reproducing them in the laboratory has more often than not been ineffective. Why?
Some types of vegetables, such as oranges, and also the cruciferae family, which includes cabbage, broccoli, cauliflower, and brussels sprouts, quite obviously protect from the risk of cancer. Many substances identified in these groups were found to be beneficial. We speak mostly of phytochemicals, products we call 'biologically active,' and polyphenols as well as other compounds. All have proven protective effects but we weren't able to use them to create a magic pill, a supplement able to replace the properties of vegetables. This is true for very complex compounds on their own and also applies to vitamins, like vitamin C or A. Why? Because it is the vegetable product on its own that is the optimal source to prevent tumors. 

The anticancerous properties of garlic are well known. Eaten raw, it is difficult to digest, and can make socializing awkward. How can we gain a maximum benefit with minimal discomfort?
The problem with garlic is that we have very interesting data but still no conclusive evidence as to all its beneficial effects. Garlic plays an important role in a preventive diet, as do onions, leek and as previously said, cabbage and all members of that family.

Another interesting family is the citrus family, which is particularly rich in vitamin C. But in analyzing the specific effect of single compounds, and here we are talking about garlic as well, we couldn't identify those compounds directly responsible for this protective and preventive function. Eating garlic is certainly a great way to prevent gastric tumors, as confirmed by data in different regions like China and Italy.

You have promoted the role of wine in the prevention of certain diseases, haven't you?
Of course. Wine is another kind of food, and I'm using the word food and not drink because wine is a product of the natural fermentation of grapes. Therefore, it contains in its final expression all the active principals of fruit, especially polyphenols -- a  component of great significance because even the very color of wine, the colour red or ruby, the flavors, the fragrances, are tied to specific compounds linked to polyphenols, themselves extremely beneficial to our organism.

Is there a difference between the bioactive principals and functional properties in red and white wine? What are the advantages for each? 
In red wine the benefits are definitely more pronounced. The index of protection of red wine is 10 times higher than in white wine. This is because the tannins in grapes, not those related to the barrel but those derived directly from the grapes, and the specific nutrients, particularly the resveratrol, carry out an antioxidant action and are therefore influential in cardiovasculary prevention.  But they are also very important in the oncological field.

The problem with wine is of course that it is an alcoholic drink, so the key word is quantity, i.e. the correct consumption like any other food. The end result translates into greater longevity. Subjects who consume wine according to traditional standards, like two glasses a day of wine for men and one for women, show not only greater longevity than the immoderate consumer but also than the abstemious. So, correct and regular consumption of wine represents an advantage over non-consumption.

Does limiting red meat and increasing the consumption of fish, which protects from breast and intestine cancer, reduce the risk of cardiovascular diseases? 
Fish and legumes are alternatives to meat. Why? Because legumes contain no fat, cholesterol or other kinds of fats, therefore it is a low-calorie food with a high protein content. As for fish, its fat contains calories but the great advantage is the amount of Omega 3 fatty acids present in great quantity in the fat tissue.
Omega 3 fatty acids play several important roles.

In the cardiovascular field, they help reduce tryglicerids in the blood, improving its flow, and also have an antiagregant function on plasma, which reduces the cardiovascular risk. At the same time, these fatty acids have an important function in the oncological field by working on the apostosi and protecting at different levels from cancerogenic development. But still, we shouldn't demonize meat consumption.

Data from vegetarian populations show that this group carries less fat sediments, saturated fats, but that they eat a lot of eggs and cheese. For this reason, I'd say that vegetarians aren't more advantaged in terms of protection than people with healthy and balanced diets, which include a fair amount of lean meat.

Professor, some of your colleagues suggest staying away from products grown in some countries where they are exposed to  preservatives and anti-cryptogamics with high levels of toxicity. Is there any way to protect ourselves from the globalization of the food industry?
This is very important. Today, we know that if anti-cryptogamic products are used in the right way and if food is rinsed properly, there's no evidence of related toxicity that would lead to an increased risk of cancer.

Food contaminated by aflatoxins like grain, various kinds of seeds and nuts coming from many regions is another story. These aflatoxins can really increase the risk of cancer but are not related to the consumption of anti-cryptogamic products. So there's no evidence that either the anti-cryptogamic products or food additives will trigger a cancerogenic action. But still, using an additive just as a cosmetic remedy, like for instance for making a certain fruit pinker, is nonsense.

By now, it's common to eat products out of season. Without wanting to scare consumers, can we link nutrient-poor food to the onset of neoplasms?
Some time ago I wrote a Decalogue of the Right of Vegetables. It argued many points. The optimal approach was to consume vegetables grown within zero kilometers, in the right season, and using proper tools like sharp knives, which reduce the waste of crucial essences.

Another chapter looked at cooking. For instance it's really important to promote microwaved and steamed cooking, two great techniques. We have to think about the benefits and risks of all produce. It's crucial that we try not to damage the potential protective characteristics of vegetables by over-hyping them. In Italy, for instance, there's a shyness in using the microwave even though all the oncology North-American societies recommend doing so.

Can the progress of biogenetics help improve the quality of food? Does any proof exist that using these products leads to an increase or reduction of risk of neoplasms?
To judge this in an absolute and rigorous manner would need a relatively long time. At the moment, we don't have definitive data. Biotechnology in the nutritional field is experiencing a real evolution and is undergoing profound scrutiny. In the future, like it or not, it will be a reality.

The GM path is very sophisticated and tends to accelerate procedures that were once traditionally slow. Let me remind you that ibridation techniques exist from time immemorial anyway.