I. 14 Recommendations for Dietary Cancer Prevention
In order to summarize the past literature in the field of diet and cancer research around the world and to propose a set of global dietary guidelines for the prevention of human cancer based on the available scientific evidence, two private academic institutions, the American Institute for Cancer Research (AlcR) and the World Cancer Research Foundation (wcRF), organized 16 leading experts in nutrition, epidemiology and oncology from eight countries to collectively write a special report entitled “Food, Nutrition and Cancer Prevention” over three years. The book was published in English in 1997. In May 1999, the Chinese Anti-Cancer Society and the World Cancer Research Foundation (wcRF) jointly organized the launch of the Chinese version of the report “Food, Nutrition and Cancer Prevention” and a symposium in Beijing. In the report, 14 recommendations were made for diets, the main contents of which are as follows.
1. consume a diverse diet rich in nutrients and mainly plant-based foods: choose a plant-based diet rich in various vegetables and fruits and legumes, but it does not mean a vegetarian diet, rather plant-based foods should occupy more than 2/3 of the meals.
2. Maintain appropriate body weight: the average body mass index of the population, i.e., body mass index, BMI = weight (kg)/height (m).2 Maintain BMI between 21 and 25 throughout adulthood, while individual BMI should be between 18.5 and 25 to avoid underweight or overweight, and limit weight gain throughout adulthood to 5 kg. Adults below 18.5 are considered underweight, and Greater than 24 is overweight, and more than 30 is obese.
3, adhere to physical activity: if engaged in light or medium physical activity occupation, should be about l hours of brisk walking or similar exercise every day, but also arrange at least l hours of more vigorous sweating exercise every week, walking, cycling, playing ball, swimming, climbing stairs, rowing, room hygiene, etc. can be, but to exercise to the extent of sweating is better.
4. encouraging more vegetables and fruits throughout the year, so that the calories they provide reach 7% of the total energy: eat a variety of vegetables and fruits daily throughout the year, up to 400-500 grams of vegetables and 100-200 grams of fruits daily.
5, choose 300 to 500 grams of plant foods rich in starch and protein, and 45% to 60% of the total energy: such as cereals, beans, starchy bananas, roots and tubers, potatoes, refined sugar should be limited to 10% of the total energy provided, the individual daily intake of starchy foods should reach 600 grams to 800 grams, should also try to eat roughly processed food, the less processed food is the better ;.
6, do not drink alcohol, especially against excessive alcohol consumption. Even if you want to drink, men should be limited to 2 cups, women within 1 cup (l cup is defined as 250 ml of beer, 100 ml of wine, 25 ml of white wine), pregnant women, children and adolescents should not drink alcohol.
7, meat foods: the intake of red meat (referring to beef, lamb, pork and their products) should be less than 10% of the total energy, and should be less than 80 grams per day, preferably choosing fish, poultry or meat from non-domestic animals as the best.
8, total fat and oil should provide 15% to 30% of the total energy, limit the fat content, especially animal fat more food, vegetable oil should also be moderate, and should choose vegetable oil containing monounsaturated fat and low hydrogenation.
9. salt restriction: adults should not consume more than 6 grams of salt per day from all sources, including a variety of foods with salt curing restrictions.
10, proper storage of food: try to reduce the contamination of food by mold, should avoid food contaminated by mycotoxins or stored at room temperature for too long, and preserve food to avoid mold.
11, food preservation to preserve quality and freshness: easily perishable food at the time of purchase and at home should be refrigerated or other appropriate methods of preservation, incomplete food is best kept frozen.
12, additives and residues in food: additives and residues in food and various chemical contaminants should be developed and monitored for their safe dosage, and strict management and monitoring methods should be developed. Additives, contaminants and residues in food when the content is below the level specified by the state, their presence is harmless, but the indiscriminate or improper use may affect health, can be taken to flush, peel, soak, heat methods to reduce the harm.
13. nutritional supplements: taking nutritional supplements cannot reduce the risk of cancer, most people should obtain various nutrients from their diet and rely on but not use nutritional supplements, vitamins and trace elements are not more than necessary, and excessive consumption may bring toxic side effects.
14. food preparation and cooking: cook meat and fish at a lower temperature when eating them, do not consume burnt meat and fish, and do not frequently consume sizzling, smoked and smoked meat and fish, and occasionally consume them mixed with fresh vegetables and mixed food.
The above recommendations, if achieved, can reduce the risk of cancer by 30% to 40%. If you add non-smoking, the risk of cancer can be reduced by 60% to 70%. Dr. T.colin.cam pben, scientific advisor of the International Foundation for Research on Cancer, considers the report “Food, Nutrition and Cancer Prevention” a milestone in scientific research in the food and nutrition industry, and the 14 dietary recommendations are applicable to all countries in the world and will play an important role in guiding people to improve their health. The report “Food, Nutrition and Cancer Prevention”, in addition to the above 14 recommendations for diet, also recommends not to smoke and chew tobacco, and discourages the production, promotion and use of tobacco in any form.
II. Overview of our diet for cancer prevention
(I) Daily diet and cancer
1. High-fat diet: Several research results prove that fat accumulation can lead to the body’s insensitivity to estrogen and elevated estrogen content, which is a hormone closely related to colon cancer and breast cancer and prostate cancer. Compared with Americans, Chinese recipes are relatively low in fat and high in fiber. The incidence of breast and rectal cancer is higher in American women than in Chinese women, and prostate and bowel cancer is higher in American men than in Chinese men. Moreover, there are more fat people than thin people among cancer patients. In addition, some scholars believe that too much fat in food will increase the incidence of testicular and uterine cancer.
2.Protein imbalance: common breast, colon, rectal and pancreatic cancers are associated with protein imbalance. The relationship between protein imbalance and cancer is more complicated. The proportion and composition of protein in various foods are very different, and the content of essential amino acids is also different. Generally speaking, the protein eaten every day should not only meet the needs of the body, but also be in proper proportion. In general, the daily protein intake should not only meet the body’s needs, but also be in the right proportion. Long-term protein deficiency or excess may promote cancer. Many people, such as those who have lost too much weight and are basically vegetarians, may be induced to develop cancer due to insufficient protein in their bodies. In order to meet the protein needs of human body, some lean meat, fish, shrimp, eggs, milk and other foods can be consumed appropriately. If you eat too little meat food, you can eat more bean products to supplement the protein deficiency.
3, carbohydrate imbalance: carbohydrates are the source of heat energy to provide the body, involved in a variety of metabolic activities in the human body. Carbohydrates are sugars. It includes monosaccharides, disaccharides and polysaccharides. Carbohydrates are directly related to pancreatic cancer and breast cancer. In particular, deeply processed and beautifully made carbohydrate-containing foods lack vitamins, inorganic salts and fiber needed by the body, which are extremely detrimental to the body’s fight against diseases. In addition, the growth of cancer cells relies on the anaerobic enzymatic action of sugar rather than the oxidative breakdown of sugar to provide energy as in normal cells. Excessive consumption of sugar may provide certain conditions for the growth and reproduction of cancer cells.
4.Low vitamin: Fiber can not only stimulate intestinal peristalsis, but also absorb and dilute carcinogens in the intestine, so that toxic substances can be discharged from the body in time. Too little fiber in food can lead to slow intestinal peristalsis and retention of toxic substances, which will increase the reabsorption of these toxic substances from the intestine by the body. Finely processed food contains less fiber, and long-term consumption of fine meals can slow down intestinal peristalsis and make feces stay in the intestine for too long, which is not conducive to the elimination of toxins in the body, thus inducing colon cancer. Therefore, it is important not to neglect brown rice, wheat bran, coarse noodles, celery, leek, rape, kelp, nori, mushrooms, etc., which contain a lot of fiber, and to eat more consciously to prevent the occurrence of colon cancer.
5.Vitamin deficiency: vitamin is an indispensable and important substance in human body. Insufficient vitamins can not only lead to the occurrence of many diseases such as ulcers and skin diseases, but also increase the incidence of tumors. Vitamin A, C and E play an important role in the prevention of tumors. Vitamin A can promote the immunity of the body, and vitamin C and E can block the formation of nitrosamines, while playing a role in cancer prevention. Vitamins are widely found in foods such as fresh vegetables and fruits. Research proves that eating vegetables and fruits rich in carotenoids can reduce the occurrence of lung cancer.
6.Trace element deficiency: trace elements account for a small proportion in human body, but their role in the body cannot be ignored. In recent years, more and more studies have found that trace elements have a close relationship with the occurrence of cancer. In some areas of China with a high incidence of lung cancer, it is found that the blood selenium content of healthy people is low, while the blood selenium content of cancer patients is even lower, and in areas with a high incidence of liver cancer, it is found that there is a lack of iron and manganese in water and soil, and when the human body lacks these two elements, it will lead to a decline in immune function and thus induce liver cancer. It has been reported that the lack of molybdenum in the diet can lead to the development of esophageal cancer; iodine deficiency increases the chance of breast cancer, etc. Therefore, it is important to pay attention to the intake of micronutrients in the diet to prevent the occurrence of cancer
(II) Suggestions for cancer prevention diet
1. Maintain proper weight, quit smoking, strengthen exercise, and choose reasonable recipes.
2.Food should be diversified because the content of various nutrients in food is very unbalanced, and the combination of various foods should be reasonable, not picky and not partial, not to eat fixed and unchanging food, but to match meat and vegetables and to combine coarse and fine. And cooking should be reasonable.
3, reduce the intake of total fat, the intake of animal and plant fatty acids should be a certain ratio of scientific ratio should be 2:1, so that the amount and ratio of saturated fatty acids and unsaturated fatty acids to meet the needs of the body.
4, improve the intake of high-fiber foods like cereals, beans, fruits, vegetables, especially the amount of vitamin-rich green leafy vegetables, to ensure that the daily intake of not less than 500 grams.
5, try to reduce the use of alcohol, carbonated beverages, try not to eat or eat less pickled, smoked or fried food
6, life should be regular, the pace of life is appropriate, meals should be regular, not binge drinking easy to overeat, the amount of meals in the right proportion.
(C) daily life diet cross tips
According to the recommendations of the Chinese Nutrition Society and the American Health Food Guide, a reasonable diet can be summarized into two sentences and ten words: one, two, three, four, five, red, yellow, green, white and black.
”One” refers to the daily consumption of one bag of milk (or yogurt) containing 250 mg of calcium, which can effectively improve the generally low dietary calcium intake in China.
”Two” refers to the daily intake of carbohydrates 250 to 350 grams, equivalent to 6 to 8 taels of staple food.
”Three” refers to the daily consumption of three portions of high-protein food, each portion refers to: 1 tael of lean meat; or 1 egg; or 2 taels of tofu; or 2 taels of chicken and duck; or 2 taels of fish and shrimp.
”Four” refers to four phrases: coarse and fine (coarse and fine grains together); not sweet and not salty (6 to 7 grams of salt per day is the best for Guangdong type diet, 8 to 9 grams for Shanghai type is the next best.) (3, 4, 5 meals), 7 or 8 minutes full.
”Five” refers to 500 grams of vegetables and fruits per day.
”Red” refers to a small amount of red wine 50 to 100 ml per day to help increase high-density adiponectin and blood circulation to prevent atherosclerosis.
”Yellow” refers to yellow vegetables, such as carrots, sweet potatoes, pumpkins, tomatoes, etc., which are rich in carotenoids and have the function of improving immunity for children and adults.
”Green” refers to green tea and dark green vegetables. Green tea has a clear anti-tumor, anti-infection effect.
”White” refers to oat flour or oatmeal. It can lower blood cholesterol and triglycerides, and has a significant effect on diabetes.
”Black” refers to black fungus, which can reduce blood viscosity and blood cholesterol, and help prevent thrombosis.