What to Eat to Prevent Cancer?
Here are some anti-cancer diet rules from research.
The causes of cancer are plural, but diet plays directly or indirectly an important role. By taking care of your diet, you can also reduce your risk of cancer. And even though epidemiological studies can not lead to cause-and-effect linkages, there is a convincing case for certain foods and certain ways of eating when they are compared with experimental evidence.
What diet to adopt in cancer prevention? Here are some simple, safe but non-exhaustive rules that can be drawn from current knowledge.
Rule # 1: favor vegetables
Fruit, oilseeds, vegetables, and legumes all have many cancer protective substances. Indeed, plants to grow well must protect themselves from many aggressors. And the phytochemicals that protect them are also those that slow down the processes involved in cancer.
Against cancer, we should ideally consume 7 to 10 servings of vegetables and fruits a day, making sure to vary the colors: white, red-pink, blue-violet, yellow-orange, green. Some families may be privileged:
The cruciferous family
Cruciferae (Brussels sprouts, broccoli, watercress, cauliflower, Chinese cabbage, cabbage, turnip, radish …) contain two families of exceptional compounds that help evacuate carcinogens before they have had the time to cause damage in the body: isothiocyanates (including sulforaphane, well known) and indoles. According to the research, the cabbage family is one of the main contributors to the anticancer effects of plants. And those who eat the most are those who are most protected against the disease.
- Of the crucifers, broccoli and Brussels sprouts appear to be the most protective .
- To benefit from the virtues of cruciferous, it is better to cook them as little as possible (cooking al dente) in a minimum of liquid because the protective substances are soluble in water and sensitive to heat. Steam or wok cooking are therefore recommended.
- Also make sure to buy them and cook them fresh, as well as chew them well.
- 3 to 4 servings a week seem to be a good dose of protection from the studies.
Red fruits (strawberries, raspberries, blueberries, blackberries, cranberries) help to detoxify the body and help reduce free radical damage thanks to a phytonutrient: ellagic acid, from the polyphenol family. They are also rich in anthocyanidins and proanthocyanidins, other polyphenols with anticancer potential.
- It is in raspberries, strawberries and blackberries that ellagic acid is the most assimilable.
- These berries can be eaten all year round using frozen (preferably) or dried products.
- Add them to yogurts, desserts, porridges, mueslis… You can also eat them raw for pleasure.
- A consumption of 100 to 200 g per day seems the most protective.
The case of soy
Asians suffer less from prostate cancer or breast cancer than Westerners. An effect that would be attributable to their high consumption of soy (while in the West we eat very little). The anti-cancer properties of soybeans are thought to be due to its isoflavones that have a structure similar to that of sex hormones and could, by binding to receptors, interfere with the development of hormone-related cancers, such as breast or prostate cancer. . Experimental studies are sometimes contradictory, but the epidemiological studies taken collectively do not show that women who consume soy have a higher risk of breast cancer, and they could even benefit from it, especially after a diagnosis of cancer. prevention of recidivism.
- It does not seem risky, and it may be a good thing to consume soy, for example by targeting 50g of whole food per day.
- In particular, favor soybeans in the form of beans (fresh beans called edamame are eaten directly in their husks after cooking, the dry ones are cooked like lentils).
- Specialists advise to stick to, for example, 1 or 2 daily servings: for beans: 100 to 200 g; for soy milk (tonyu): 1 to 2 glasses; for tofu: 30 to 60 g.
- Supplements based on isoflavones are not recommended.
Rule # 2: Use the right fats
The typical Western diet may be too rich in potentially inflammatory fats (linolenic acid sunflower oils, corn, soy and its derivatives of the omega-6 family) compared to neutral or low inflammatory fats (oleic acid, alpha-linolenic acid and its omega-3 derivatives). An inflammatory medium is indeed conducive to the development of cancer. Omega-3s may also have a positive effect directly on cancer cells.
Olive oil would be naturally anti-inflammatory . In addition, experimentally several polyphenols of olive oil have anti-cancer properties. According to the PREDIMED study, adding olive oil to a Mediterranean diet (which already contains it) could increase the anti-cancer effects of this diet. This effect is due in particular to two of the polyphenols of olive oil:
– Oleocanthal which, according to experimental studies, has antioxidant, anti-inflammatory, neuroprotective and inhibitory properties of cell proliferation …
– Hydroxytyrosol, a powerful antioxidant that also has antiproliferative and anti-inflammatory properties. It is also present in red wine.
- Omega-3s are found in flaxseed, walnuts, canola oil, flaxseed oil, camelina oil and fatty fish (sardines, mackerel, tuna, salmon…). According to a study in late 2017, it would be better to focus on omega-3 fish than flaxseed when we want to prevent cancer, but there is no consensus on the subject. Use olive oil and rapeseed oil (virgin, organic) for salads (you can also heat the olive oil without excess) at a rate of 2 to 4 c. to s. per day.
2 apriori favorable eating habits
Although the formal evidence is not yet fully established, there are still many good quality studies indicating that the Mediterranean diet would help reduce the risk of cancer, including breast and prostate cancer. Rich in vegetables, fruits, whole grains, legumes, olive oil, and limited in dairy products and meat, this food mode is anyway close to the recommendations given in this article.
Vegetarian eating also seems to be a good way to protect oneself from cancer, which is logical since this mode of feeding emphasizes protective plants while excluding two families of foods known to favor its appearance: red meat and meat. delicatessen.
Rule # 3: Little salt and lots of spices in the kitchen
Garlic, onion, chives and their cousins shallot and leek contain sulfur molecules that help protect genes from deleterious mutations and may reduce the risk of developing cancer (especially those of the digestive system).
Garlic also has a specific protective effect against nitrites and nitrosamines (compounds found in over-grilled meats and deli meats). But members of the Allium family would also have the ability to prevent the growth of cancer cells.
Another advantage of herbs and spices: they reduce the amount of salt without losing flavor. There is indeed a consensus among researchers to recommend not swallowing more than 6 g of salt per day (ie 2400 mg of sodium). Excess salt is linked to an increased risk of stomach cancer.
- The protective molecules of these foods are released by mechanical breaking: it is therefore necessary to chop or crush them (garlic) so that they are effective.
- Add chopped garlic or onion in raw vegetables to other steamed vegetables, wok or soups daily.
- A daily serving equivalent to 2 cloves of garlic and 1 onion or 2 shallots chiseled seems the most protective.
- Freshly crushed garlic mixed with a little olive oil seems the best source of anti-cancer compounds, so it should be preferred to supplements.
Side spices, you can use turmeric (associated with pepper) and ginger, two spices “weak”. Spices are a kind of concentrate of protective nutrients (especially antioxidants). All are good to add to the dishes but two of them have proven to be particularly interesting against cancer, because they have in addition to strong anti-inflammatory properties: turmeric and ginger. Turmeric and its curcumin, in vitro and on animals, can prevent tumors or block their growth. But there is no confirmation in humans.
- Prefer spices from organic farming, because spices and aromatics concentrate pesticides.
- In order to increase the assimilation of turmeric, it must be mixed with a little pepper and fat (olive oil, for example). 1 teaspoon per day is the ideal dosage to benefit from its virtues.
- Raw turmeric has a taste but its flavor fades on cooking, so it can be easily integrated into most dishes (vinaigrettes, soups, marinades, cereals …).
- Grated or chopped fresh, ginger delicately perfumes dishes made from fish, meat or vegetables (it is traditionally used in wok dishes). It can be used also marinated with fruits and lime or herbal tea.
- Consume about 10 g of fresh root (ie 1 to 2 g of ginger powder) per day to get the best of its virtues.
Rule # 4: Choosing your carbohydrates
Many studies show that the explosion of sugar consumption contributes to the epidemic of obesity and cancer. What relationship can there be between consuming too much sugar and the propensity to develop cancer? Three major elements: the high secretion of insulin, inflammation and overweight which is a risk factor for diabetes and associated cancers. Eating less added sugar (sodas, cookies, confectionery, of course, but also beware of ultra-processed foods!) And choosing the best carbohydrates would help limit your risk of cancer.Basically, it is preferable carbohydrates that have the least aggressive effect on insulin levels, that is to say those with low glycemic index: whole grains, legumes, sweet potato …
- Avoid ultra-processed foods , and cook as much as possible at home.
- Avoid sodas, fruit juices with added sugar, and limit fruit juices
- More practical tips in The New GI Diet.
Rule # 5: Drink Green Tea
As for drinks, there are good choices to make. Drinking tea could be a good strategy against cancer.
Both black and green teas are very rich in antioxidants, but green tea has an additional advantage against cancer: it contains large amounts of epigallocatechin gallate (EGCG), a polyphenol.
Green tea helps detoxification and allows experimentally to stop the growth of cancer. In vitro, EGCG inhibits the growth of several cancer cell lines (leukemias, kidney, skin, breast, mouth and prostate cancers).
- Focus on Japanese green tea, richer in EGCG than Chinese.
- Infuse for 8 to 10 minutes to be sure to take advantage of its anti-cancer properties.
- Drink every day 3 cups of 250 ml.
Rule # 6: limit red meat and cold cuts
The World Cancer Research Fund (WCRF) advises to limit the consumption of red meat: no more than 500 g per week, and even more that of deli meats. In observational studies, red meat is associated with a moderately increased risk of digestive cancers. This risk is more pronounced with cold cuts, because of the presence of preservatives (nitrates and nitrites), which can give birth in the presence of iron to carcinogenic compounds, nitrosamines.
- Replace red meat with white or fish.
- Prefer white hams without nitrites (there are now some) and for dry hams, buy only those with only two ingredients: ham and salt (this also exists!). Traditional sausages are also likely to contain less additives.
Rule # 7: reduce toxins by favoring mild cooking
While it is difficult to avoid environmental pollutants, if carcinogens can not be completely avoided, there are protective actions in the kitchen that reinforce the effects of the preventive diet described here. This happens mostly in cooking.
Cooking at high temperatures causes the creation of molecules that are toxic to the body and increase the risk of cancer.
- Steam cooking should be preferred as much as possible. The wok, allowing a short cooking, can also be an interesting mode.
- If you can not give up the prospect of a barbecue, it is better to marinate the meat before in oil, spices and onions and garlic.
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