The eight biggest food rumors in 2014, how many did you believe?

There is never a shortage of rumors in life, especially in today's information age, where the generation and spread of rumors are far more intense than the refutation of them. Driven by new mobile media, the food industry has become the area that is most likely to attract attention and where rumors are most likely to arise. 2014 is about to end, and we have invited authoritative food experts to select the hottest rumors in the food circle this year and interpret them one by one.

1. Small molecule collagen anti-aging

Rumor tracking: At the beginning of the year, artist Jimmy Lin became a hot topic because of his "reverse growth". Among the products launched by his company, there is a collagen drink with "small molecule collagen" as the main raw material. Jimmy Lin said that the secret of his eternal youth lies in this.

Expert opinion: Yun Wuxin, a Ph.D. in food engineering from the Department of Agriculture and Biology at Purdue University in the United States, said that there is no evidence that hydrolyzed collagen (or the so-called "small molecule collagen") can help with beauty and skin care. Hydrolyzed collagen is equivalent to carrying out part of the human digestion process outside the body, so the digestion and absorption speed is faster after ingestion. In addition, many dipeptides and tripeptides in hydrolyzed collagen are directly absorbed into the blood, but they cannot enter cells as raw materials for protein synthesis. In other words, they are indeed absorbed into the blood, but cannot be used and are finally excreted from the body.

2. Oxygen-enriched water can “replenish oxygen”

Rumor tracking: Drinking water can "replenish oxygen", and the dissolved oxygen content is 6 to 10 times that of ordinary drinking water... At the end of February, Hangzhou Wahaha Group launched an oxygen-rich weak alkaline water called a "revolutionary drink", claiming that drinking a bottle of oxygen-rich water can absorb the high concentration of oxygen in the water through the digestive tract mucosal permeation

Expert opinion Yun Wuxin said that first of all, oxygen-rich water is not magical. It will release oxygen when the bottle is opened. Secondly, absorbing oxygen by drinking water is not very realistic. The water we drink enters the digestive system. Although some "scientists" have proposed the theory of "absorbing high-concentration oxygen in water through infiltration of the digestive tract mucosa", it has not been recognized by the scientific community. Replenishing oxygen by drinking water is not theoretically feasible. Finally, the oxygen content in the water is too low compared to what we can breathe. Even if all the oxygen in oxygen-rich water can be absorbed by the human body, the amount is negligible compared to breathing.

3. Genetically modified foods are harmful

Rumor tracking: In early March, many websites launched a documentary about GMOs shot by TV host Cui Yongyuan in the United States, which received a large number of views and reposts. At the CPPCC meeting, he proposed a proposal to ban the commercialization of genetically modified staple foods and immediately terminate the genetically modified projects of seed companies.

Expert opinion Luo Yunbo, dean of the College of Food Science and Nutritional Engineering at China Agricultural University, pointed out that so far, no adverse effects of approved genetically modified foods on human health have been found. Genetically modified organisms only change the genes of crops. When these changed genes are eaten by the human body, they will be digested along with other genes and will not change human genes. Genetically modified foods must undergo strict safety evaluation before entering the market. It should be said that the genetically modified foods we can buy are safe and can be eaten with confidence.

4. Fruit and milk cannot be eaten together

Rumor tracking: Various taboos regarding drinking milk are widely circulated among the people. In a TV show this year, an expert told everyone through an experiment of "pouring orange juice into milk to produce flocculent precipitation" that you should not eat sour fruits within 1 hour before and after drinking milk.

Expert opinion: Hu Changli, a doctor from the Key Laboratory of Functional Dairy Products of China Agricultural University, said that precipitation when exposed to acid is the basic property of "casein" in milk. Even if you don't drink milk with juice, it will settle in your stomach. Because there is a large amount of gastric acid in the stomach, its main component is hydrochloric acid, which is much more acidic than the fruit acid in fruits. After milk enters the gastrointestinal tract, it will first come into contact with gastric acid and flocculate before further digestion and absorption. From another perspective, fruit and milk are a good match, and the nutritional content of the two is a perfect match.

5. Microwave heating causes cancer

Rumor tracking: The claim that microwave ovens cause cancer has been around for a long time. This summer, a post titled "Stop using microwave ovens, it causes cancer!" was widely circulated on WeChat. The post claimed that food heated in microwave ovens can produce carcinogens, which once again aroused people's concerns.

Expert opinion: Fan Zhihong, associate professor at the College of Food Science and Nutritional Engineering of China Agricultural University, pointed out that microwaves only heat water molecules in food. The food itself does not undergo chemical changes and will not produce carcinogens. Lu Jianguo, director of the Comprehensive Inspection Department of the National Household Appliance Quality Supervision and Inspection Center, also said that microwave ovens of qualified quality have undergone rigorous testing and repeated experiments, and their microwave leakage and radiation generated are within the standards prescribed by the state. Under normal use, they will not cause harm to the human body, nor will they cause harm through the food they heat.

6. Mushrooms are rich in heavy metals

Rumor tracking: In October this year, an article titled "Eat less mushrooms" circulated on WeChat. The article said that a doctor from the University of Zurich in Switzerland who studies fungi said that although mushrooms are good, they have a strong ability to accumulate heavy metals such as lead and mercury, up to more than 100 times.

Expert opinion: Professor Lin Xinying from the Institute of Nutrition and Food Hygiene at Shandong University told reporters that compared with some foods, mushrooms do have a higher ability to accumulate heavy metals. However, whether the heavy metal content of mushrooms exceeds the standard is mainly related to their growing environment. Most of the mushrooms sold on the market now are grown in culture media prepared with agricultural and forestry by-products such as cottonseed hulls and bran. Therefore, the chance of them coming into contact with heavy metals is very small, let alone exceeding the heavy metal standard. In addition, mushrooms contain polysaccharides, which can inhibit the dissociation of heavy metals, making them unable to become ions in the body and therefore difficult to be absorbed by the intestines. Therefore, even if people eat mushrooms, the impact on the human body is relatively small.

7. “Jicao” has magical effects

Rumor tracking: Jicao 5X Cordyceps sinensis, a product that claims to be able to be "eaten by mouth" and has the effects of improving human immunity and anti-tumor, is well known to everyone due to its high price and frequent advertisements. In November this year, Wang Hai, a well-known anti-counterfeiting expert, sent Jicao 5X Cordyceps Classic Lozenges for inspection, and the results showed that the lozenges did not contain cordycepin.

Expert opinion: There is no evidence in Western research to support the miraculous effects of Cordyceps, and the research conclusions tend to be "negative." In scientific literature, most of the research on Cordyceps is done by Chinese people, and the research level is basically at the level of "ingredient identification". It can be said that the research on Cordyceps still has a long way to go before it can be shown to be effective in human trials. There are currently no scientific test results to show that Cordyceps lozenges are easier to absorb or have better effects.

8. Brewing tea in a stainless steel cup is toxic

Rumor tracking: After the winter came, some media filmed a video saying that after making tea in a stainless steel cup for 72 hours, the cup became "corroded". Because stainless steel contains toxic heavy metal chromium, which will be released into the tea

Expert opinion Yun Wuxin said that it is not easy to corrode stainless steel. Stainless steel needs to be soaked in strong corrosive conditions for a long enough time before visible corrosion results may occur. Tea water is nearly neutral and has a very low ionic strength, making it almost non-corrosive, let alone causing visible corrosion within dozens of hours. The most likely possibility is that tea stains have deposited on the cup and are considered "corrosion". In addition, stainless steel will only corrode under certain circumstances, and some chromium will be dissolved, but the content is extremely small. There is no need to worry about using stainless steel tableware that meets national standards in daily life.