Why does yogurt not cause cancer?

Flour fermented into steamed bread is easy to digest and absorb, and milk fermented into yogurt has the same effect. During fermentation, about 20% of sugar and protein in milk are broken down into small molecules (such as galactose and lactic acid, small peptide chains and amino acids). The fat content in milk is generally 3% ~ 5%. After fermentation, the fatty acids in milk can be increased by 2 times compared with raw milk. These changes make yogurt easier to digest and absorb, and improve the utilization rate of various nutrients. Yogurt is fermented from pure milk. Lactic acid bacteria can not only retain all the nutrients of fresh milk, but also produce various vitamins necessary for human nutrition during fermentation, such as VB 1, VB2, VB6, VB 12, etc. Even for people with lactose indigestion, eating yogurt is not easy to cause bloating, flatulence or diarrhea. Fresh milk is rich in calcium, and minerals such as calcium will not change after fermentation, but lactic acid produced after fermentation can effectively improve the utilization rate of calcium and phosphorus, so calcium and phosphorus in yogurt are more easily absorbed by human body.

Yogurt is a rich source of probiotics. Probiotics refer to a kind of intestinal physiological bacteria beneficial to human life and health, such as Bifidobacterium, Lactobacillus acidophilus, Lactobacillus casei and other lactic acid bacteria. At present, there are many kinds of yogurt products on the market, including solidified yogurt, stirred yogurt and juice yogurt with different juices, which are sweet and sour and suitable for different tastes. No matter what kind of yogurt it is, it is characterized by containing lactic acid bacteria. These lactic acid bacteria will secrete substances beneficial to human health when they propagate in human intestine, so yogurt has more benefits to human body: First, it can decompose lactose and protein in milk, making it easier for human body to digest and absorb; Second, yogurt can promote the secretion of gastric juice, increase appetite and strengthen digestion; Third, lactic acid bacteria can reduce the production of some carcinogens, so they have anti-cancer effects; Fourth, it can inhibit the reproduction of spoilage bacteria in the intestine and weaken the toxins produced by spoilage bacteria in the intestine; Fifth, it has the function of lowering cholesterol, especially suitable for people with hyperlipidemia; Sixthly, generally speaking, patients take or inject a lot of antibiotics to treat diseases or prevent infection, which makes the intestinal flora change greatly, and even some beneficial intestinal bacteria are suppressed or killed, resulting in flora imbalance. Yogurt contains a lot of lactic acid bacteria. Drinking 250 ~ 500ml a day can maintain the normal intestinal flora balance and adjust the beneficial intestinal flora to a normal level.

The research results of graphic yogurt in Yongchuan, Japan, generally show the nutritional efficacy of fermented yogurt. Yogurt contains a growth active factor, which can enhance human immune function, and is beneficial to health, disease resistance and anti-aging.

The surface of pickled cabbage is often covered with a white mold coating, from which a mold can be isolated, which can promote the carcinogenesis of methylbenzyl nitrosamine on mouse stomach and rat esophagus in animal experiments. Amines are not only abundant in nature, but also molds can often increase the content of secondary amines in food. Therefore, frequent consumption of sauerkraut provides the necessary conditions for the synthesis of nitrosamines. That is to say, pickled cabbage contains a lot of nitrosamines, which can be synthesized in the gastrointestinal tract under appropriate conditions after entering the body, causing cancer, mainly digestive tract cancer and gastric cancer.

Nitrite used as a preservative in meat products has always been regarded as a carcinogen, but scientists at the National Institutes of Health recently discovered that this carcinogen can be made into drugs to treat sickle cell disease and heart disease. This discovery is shocking.

/kloc-for 0/00 years, scientists thought that nitrite had no benefits, but today, scientists have discovered its value. According to a report by NBC on September 5th, Dr. Mark T. Gladwin and Dr. Richard Cannon, a cardiologist, accidentally discovered the medicinal value of nitrite when they were studying a compound related to nitrite-nitric oxide. Nitric oxide can dilate blood vessels and increase blood flow, but it cannot be used as medicine. Nitrite, which is often used as a food preservative, is similar to nitric oxide and can be used as medicine, so two scientists thought of nitrite.

Subsequently, scientists conducted clinical trials. They injected a small amount of nitrite into healthy volunteers, and as a result, the blood flow of volunteers tripled. When volunteers exercise, the content of nitrite in the body immediately drops linearly, indicating that the body is actively using nitrite. Therefore, scientists believe that nitrite can be used as a drug to treat sickle cell disease, heart disease, cerebral aneurysm and other diseases related to blood flow.

In this regard, Dr. Gladwin joked, "We regard human organs as hot dogs. Adding nitrite is equivalent to adding protective measures to protect the heart, lungs and brain from death due to lack of oxygen."

However, it is worth noting that high doses of nitrite will still produce great toxicity. Eating nitrite by mistake will lead to nitrite food poisoning, and long-term use will even lead to esophageal cancer and gastric cancer.

From the perspective of food hygiene, nitrite, as a food additive, can be used in the production of sausage, meat dishes, dog meat and other meat products. Its main function is to keep meat products bright red, inhibit bacteria and enhance flavor, but the scope and dosage should be strictly controlled. The national standard GB5009.3396 stipulates that the nitrite content in meat products should not exceed 30 mg/kg and should be properly kept. According to the statistics of 9398 cases of food poisoning in Laicheng District Food Supervision Office, there have been four cases of nitrite food poisoning in recent five years, accounting for 40% of the total number of people, of which three cases were caused by poor management, accidental addition and accidental consumption of nitrite by meat producers. In addition, due to the chemical composition of the soil, some vegetables such as celery, leek, spinach, cabbage and lettuce contain a lot of nitrate, especially in pickled or rotten vegetables, which is reduced to nitrite by intestinal bacteria in human body, causing harm to human body. Therefore, in addition to the strict management and control of nitrite consumption by meat producers, food supervision agencies also remind consumers not to eat meat products with abnormal color, spoiled vegetables and pickled pickles, and it is strictly forbidden to drink bitter well water. ?

The causes of nitrite poisoning are as follows: First, nitrite and other items are placed near food, kitchen utensils and drinking water, and chefs accidentally mix nitrite into food. The second is to eat rotten vegetables or other foods. Generally speaking, food contains trace amounts of nitrate. If it is stored for too long or improperly, bacteria will multiply and nitrate can be converted into nitrite. In rotten vegetables and rotten food, nitrite will rise a hundredfold. Leftovers can also produce nitrite. Pickled vegetables and pickles can also produce nitrite, but the peak of nitrite production appears on the seventh day of pickling. If you eat it after half a month, the nitrite in it will be greatly reduced.

Nitrite poisoning not only has serious poisoning symptoms in the near future, even life-threatening, but also may have a certain cumulative carcinogenic effect, so we must be vigilant and take effective preventive measures. First of all, let the masses, especially the chefs and managers in restaurants and canteens, have common sense to prevent nitrite poisoning and avoid eating nitrite by mistake. The place where nitrite is stored should be strictly separated from food, cooking utensils and drinking water. Secondly, we should strictly follow the requirements of food hygiene, do not eat rotten vegetables and rotten food, and resolutely throw away overnight dishes and stale leftovers. Third, we should eat fresh vegetables and fresh meat. Food should not be stored in the refrigerator for too long. It's best to buy and eat now, and resolutely don't eat bad food with peculiar smell. Once nitrite poisoning is found, it should be sent to the hospital for emergency treatment immediately to minimize the adverse consequences. (Guangming Daily)

Nitrite will not volatilize due to high temperature cooking. Although it is soluble in water, its properties are relatively stable. So boiling and heating are impossible to eliminate.

China residents have a long-standing habit of eating sauerkraut, especially in the cold and rainy areas in the north. There were not many fresh vegetables in the past. For a long time, eating sauerkraut has become a traditional eating habit. However, from the investigation of preventing esophageal cancer in Taihang Mountain area, it is found that eating sauerkraut is related to the occurrence of esophageal cancer. Some surveys show that people who eat sauerkraut in large quantities for a long time have a higher chance of developing esophageal cancer. Feeding concentrated sauerkraut water to experimental mice is also easy to get esophageal cancer and precancerous lesions. This reminds people that eating a lot of pickled and fermented food often may lead to cancer.

Some people found that the precursors of nitroso compounds are nitrite and nitrate when studying the carcinogenic mechanism. They exist widely in nature, and some of them are inevitable. Such as drinking water, radish, Chinese cabbage, beet and so on. They all contain a lot of nitrate, and the nitrogen fertilizer widely used in farmland is also based on nitrate. The problem is how to prevent these components from becoming nitrosamines and reduce the intake of nitrite. At present, in order to preserve corrosion and enhance color, some preservatives are added to food, such as nitrite in finished products made of bacon, ham, sausage, fish and meat. If it is within the dose range allowed by the state, it will generally not affect health, but if it is added excessively or eaten excessively, it will be harmful to health. Secondly, the synthesis of nitroso compounds in vivo should be avoided. Some people think that under certain circumstances, nitrate may be reduced to nitrite in the stomach and combined with protein decomposition products in the stomach to form nitrosamines, which are easy to cause cancer over time. In this way, it is necessary to maintain the health of your gastrointestinal tract, such as maintaining normal bacterial activities in the mouth and stomach, avoiding insufficient gastric acid, and not letting too much gastric acid. Then eat less preserved and stale food. There are pickled vegetables, pickles, pickles, fish and shrimp sauce in the south, all of which contain nitrosamines, so it is not advisable to eat more. The nitrite in the leftovers at room temperature will increase rapidly with the passage of time, so it is not suitable for eating from the perspective of cancer prevention.

Vitamin C plays an important role in blocking the synthesis of nitroso compounds in the stomach. Green leafy vegetables, kiwifruit, pineapple, oranges and other fruits all contain a lot of vitamin C. Eating more fresh vegetables and fruits is good for cancer prevention. Other studies have shown that malt, almonds and walnuts contain more vitamin E, which is also good for blocking carcinogens. "The road is one foot high and the magic is ten feet high." Although the food we eat every day will inevitably contain precursors of carcinogens, some carcinogens are hard to prevent, and some research needs to be further studied, but as long as we take it seriously, it will be good for health. Kimchi is preserved by pure lactic acid bacteria.

Kimchi is also a traditional food that we often come into contact with, but many kimchi often have the quality problem of nitrite exceeding the standard. Recently, some pickle processing plants in Yinxian, Ningbo are transforming their processing technology to solve this problem.

There are many kinds of pickles, including local pickles, sauerkraut and pickles, as well as northern pickles and pickles. In the past, people in Hangzhou pickled vegetables in this way: after washing and drying vegetables, they pickled them with a lot of salt, then put them in jars or clay pots for a while, and then fished them out to become pickled vegetables.

According to Professor Ying, this pickling process is mainly caused by beneficial bacteria such as lactic acid bacteria, but there will also be a large number of other bacteria and microorganisms in contact with vegetables. In the special physical and chemical environment of pickling, some microorganisms can reduce nitrogen compounds in vegetables to nitrite. Nitrite can combine with hemoglobin, which reduces the oxygen transport capacity of red blood cells. If the intake is too high, it will cause acute poisoning.

Experts said that the new technology is to add cultured lactic acid bacteria as strains at the beginning of pickling, and then ferment vegetables under sealed aseptic conditions. Because the number of lactic acid bacteria added is tens of thousands of times that of the original fermentation by the traditional process, the fermentation process can be effectively controlled, and the growth of other fungi and microorganisms can be inhibited, thus reducing the generation of nitrite.

It is understood that in addition to preserves and pickles, at present, China has also begun to transform traditional food processing technologies such as ham and kimchi. However, while the safety of these foods is improved, the taste is slightly different.

For example, the taste of Yuhang candied fruit processed by new technology is basically the same as that of traditional candied fruit, but the taste of traditional candied fruit is softer. Professor Ying explained that this is because the drying process is nearly one week shorter than the sun drying process. However, with the further improvement of new technology, there is still room for improvement in taste.

Similarly, Professor Ying, who has tasted the new technology of kimchi, also said that the kimchi processed by the old technology will have better flavor and fragrance. This may be because a few beneficial bacteria have an influence on the aroma and flavor of kimchi, but they have not been found yet, so they cannot be added to the new technology for the time being.

Nitrate is a common substance, which is widely used as color developer and preservative in food processing industry. It has three functions: first, it makes meat products appear beautiful bright red; Second, meat has a unique flavor; Third, it can inhibit the reproduction and toxin secretion of harmful botulinum.

Generally speaking, as long as the content is within a safe range, it will not cause harm to people. Eating 0.2-0.5 grams of nitrite at a time will cause mild poisoning, and eating 3 grams will cause severe poisoning. Poisoning leads to hypoxia in human tissues, and even leads to death in severe cases.

Nitroso compounds are rarely found in natural foods, but they are often hidden in some foods that have undergone special processing-pickling, waxing and fermentation. Such as pickles, bacon, salted fish, bacon, bacon, cheese, sauerkraut, soy sauce, vinegar, beer, etc. , may produce nitroso compounds. Long-term intake of nitrite can also lead to nitrite poisoning.

To reduce the harm of nitrite and nitroso compounds, experts suggest that on the one hand, we should reduce our intake, including eating more fresh vegetables and meat; Eat less or no pickled products and sauerkraut; Do not eat pickles with curing time within 24 hours; Pepper, pepper and other spices are packaged separately from salt; Don't drink the water left over from the steamer that has been boiled for a long time. On the other hand, it is necessary to block the transformation of nitrite into nitroso compounds. Such as preserving food at low temperature, reducing protein decomposition and nitrite generation; Eat more vegetables and fruits rich in vitamin C and vitamin E, as well as garlic, tea and vinegar.