How much does cancer have to do with diet?

According to the report "Diet, Nutrition, Physical Activity and Cancer: A Global Perspective (3rd Edition)" published by the World Cancer Research Fund (updated every 10 years), an unhealthy diet increases the risk of many cancers.

A study published in the international medical journal Nature Communications systematically evaluated the 860 observational studies involved in the report and analyzed:

There is a definite association between food or nutrient intake and the risk of morbidity or mortality from 11 primary malignancies, providing strong evidence for the relationship between diet and cancer risk.

What dietary habits are "accomplices" of cancer? What kind of diet can prevent cancer?

01

"Cancer from the mouth" has a solid scientific basis

Researchers from the World Health Organization's International Agency for Research on Cancer and Imperial College London, UK, found that:

Overall, diet and nutrition may account for 25%~0% of the global cancer burden.

Among them, about 5%~0% is attributed to obesity factors caused by high-calorie diet and lack of physical activity; About 0% is attributed to alcohol, and about 0% is attributed to specific dietary factors, such as red meat, processed meat.

Pork, beef, etc. are foods that often appear in the daily diet, so the saying that "red meat causes cancer" may cause fear and anxiety in many people.

However, in fact, meat, especially red meat, is not carcinogenic, and an important premise of this statement is that it is eaten in large quantities over a long period of time and is not cooked properly.

For example, frying, frying, and grilling meat will produce some carcinogens and induce cancer. If you don't eat too much every day, try to avoid frying and smoking, you don't have to worry about carcinogenicity."

Moreover, compared with people in European and American countries, the average intake of red meat and processed meat in China is relatively low.

Cancer is a disease that is not caused by a single factor, and in addition to diet, genetics, environmental characteristics (exposure to toxic substances or hormonal disorders, etc.) are important factors.

The intake of milk and dairy products and calcium mentioned in the report is negatively correlated with cancer risk, and relevant experts believe that the anti-cancer effect of milk and dairy products is mainly due to the calcium in it:

1. Calcium binds free bile acids and free fatty acids to reduce their toxic effects on the colorectum;

2. It can also reduce the spread of cancer cells and promote cell differentiation by affecting different cell signaling pathways. In addition to calcium, lactic acid bacteria in dairy products are also beneficial for the prevention of colorectal cancer; Casein and lactose may increase the bioavailability of calcium.

02

5 Bad Diets Are "Accomplices" to Cancer

In fact, research on diet and cancer has been one of the hot topics in the field of epidemiology in recent years.

In addition to the latest research evidence from the previous research, there are 5 types of poor diets that have been recognized as carcinogenic "accomplices":

Deep-fried, smoked food

Repeated frying or smoking of food at high temperatures, especially charred food, can produce a large number of carcinogens.

Starchy foods, such as French fries, are prone to produce carcinogens such as acrylamide and polycyclic aromatic hydrocarbons when cooked at a high temperature of 120°C.

Grilled fish, barbecued meat and sausages grilled over an open flame or charcoal fire are high in benzopyrene, which can induce cell mutations and cause cancer.

Repeated high-temperature heating of edible oil will cause fatty acids to oxidize, crack and polymerize to produce more carcinogens, including polychlorinated biphenyls and malondialdehyde.

Pickled and processed meat

Many studies at home and abroad have shown that eating a lot of preserved foods or processed meats, such as salted fish, sausages, bacon, bacon, etc., will increase the risk of stomach cancer.

Researchers believe that nitrite contained in pickled foods can turn into nitrite amine when it enters the body, which is a strong carcinogen that increases the chance of cancerous transformation of digestive organs such as the stomach, intestines, and pancreas.

In addition, some pickled foods are high in salt, which may increase the risk of Helicobacter pylori infection and induce stomach cancer.

Due to high temperature, high salt and other processing methods of processed meat, the intake of carcinogens such as heterocyclic amines, polycyclic aromatic hydrocarbons, and N-nitro compounds has increased.

Hot food, hot drinks

The World Health Organization's International Agency for Research on Cancer (IARC) classifies hot beverages above 2°C (such as coffee, tea, etc.) as a category 0A carcinogen, saying that it has an increased risk of esophageal cancer.

Epidemiological investigations suggest that esophageal cancer, cardia cancer, and oral cancer in some areas may be related to the habit of eating hot food. Long-term eating of hot food will lead to repeated damage to the mucosa of the digestive tract, which may cause chronic inflammation and promote tumorigenesis.

Studies have found that the most suitable eating temperature for the human body is 60°C~0°C, and the maximum temperature generally tolerated is 0°C~0°C.

Moldy and spoiled food

Food mildew not only deteriorates the food sensory, but also produces strong toxins, causing people to get food poisoning, illness or cancer.

Yellow yeast yeast toxin is a metabolite of yellow yeast mold, usually seen in moldy nuts, grains and fermented foods, it is a carcinogen that can not be killed at 20 °C for 0 hours, with strong stability, long-term trace continuous intake of food containing yellow yeast yeast mycotoxin, which is considered to be an important cause of liver cancer, stomach cancer, intestinal cancer and other diseases.

Surveys and studies in Africa, Southeast Asia and other regions or countries have shown that the incidence of liver cancer is very high wherever food is seriously contaminated with aflatoxin.

alcohol

In addition to damaging the liver, there is growing evidence that alcoholic beverages increase the risk of many types of cancer.

Among them, there is sufficient evidence that alcoholic beverages are one of the causes of oral cancer, laryngeal cancer, esophageal cancer (squamous cell carcinoma), liver cancer, colorectal cancer, and breast cancer.

The association of alcohol with the risk of multiple cancers may be related to a variety of mechanisms:

Evidence suggests that the active metabolites of alcohol, such as acetaldehyde, are carcinogenic; Alcohol can be used as a dissolution to promote the entry of carcinogens into cells; Heavy alcohol consumption can lead to a lack of certain nutrients in the diet, making tissues more sensitive to carcinogenic effects, etc.

03

What kind of diet can prevent cancer?

There is no specific and exact single food when it comes to cancer prevention, but there are dietary rules to follow. On the basis of maintaining your eating habits and hobbies, you can try to achieve the following 4 points.

1) There are "trade-offs" in daily diet

Intentionally increase the intake of protein (eggs, milk, fish, meat, beans) and vegetables; Steaming, boiling, and simmering cooking processing methods are mostly used.

House: Reduce the intake of red meat and processed meat, and try to use less frying and stir-frying, especially grilling; Reduce carbohydrates with a high glycemic load, such as alcohol, refined sugar, refined rice noodles and their products; Avoid or limit alcohol consumption.

2) Eat a varied and balanced diet

Food diversity determines the diversity of gut bacteria, which determines the health of the human body; Make sure to eat a variety of foods every day – fruits, vegetables, whole grains, protein and dairy products, among others.

Be conscious of eating foods that you don't like to eat or eat less. Eat plenty of fruits and vegetables, especially those of the cruciferous family:

Such as cabbage, broccoli, cauliflower, kale, cabbage, bok choy, etc., they are rich in a variety of vitamins, minerals and some antioxidants, and sulforaphane will also promote the expression of tumor suppressor genes and reduce the incidence of tumors.

Some vegetables that can be eaten raw, preferably raw, can reduce the destruction of vitamins and folic acid by thermal processing.

3) It is better not to go to extremes in diet

Neither vegan nor meat-only is a healthy diet.

Current nutritional recommendations for cancer prevention include increasing the intake of fruits and vegetables, especially foods rich in various vitamins and dietary fiber, which may reduce the risk of digestive tract cancer, breast cancer, etc.

Meat, especially red meat, is rich in iron, protein, zinc, niacin, vitamin B12, thiamine, riboflavin and phosphorus, which are essential nutrients for the human body, and it is recommended that everyone consume them in moderation every day.

4) Arrange the eating time reasonably

Nutritional physiognomy studies have found that eating the same amount or calorie meal at different times has very different nutritional and health effects.

For healthy adults, it is recommended to eat full and good breakfast and lunch, and eat less and early dinner; Distribute the total food intake of each day according to the proportion of 4%, 0% and 0% in the morning, noon and evening, respectively; Don't eat supper, don't eat extra meals, and try to avoid eating 0 hours before going to bed.