In the hot summer, take off the ＂popular science＂ coat of these rumors

◎ Our reporter Chen Xi

　　There are endless health-related news on the Internet, but it is hard to tell the true and false "popular science". They are either from an "alternative" interpretation of a netizen, such as negative pressure wards that make patients have difficulty breathing; Or "warm tips" circulating in the circle of friends, such as Flammulina velutipes containing formaldehyde; Or "research results" from professional journals, such as strong chewing ability, not easy to suffer from Alzheimer’s disease, and drinking milk causes cancer … …

　　Today, the reporter of Science and Technology Daily will take stock of these fake popular science rumors in May one by one to help you clear the fog and find the truth.

　　Drinking milk causes cancer? Truth: Without reliable scientific basis, milk is still a healthy food.

　　The saying that "milk and dairy products are carcinogenic" has been widely circulated among the people. Recently, a paper entitled "Dairy products intake of adults in China is related to cancer risk" seems to give this statement "scientific" evidence.

　　This study is aimed at the population in China, and it has followed up 500,000 people in Chinese for 11 years. Relevant research data show that the intake of dairy products is positively correlated with the risk of cancer — — People who regularly eat dairy products have a higher overall risk of cancer.

　　At the same time, the above research data also points out the health benefits of drinking milk, such as promoting growth and development, but it seems that many netizens only care about "drinking milk in Chinese causes cancer".

　　"Academic circles at home and abroad have been talking about ‘ Is milk carcinogenic ’ In recent studies, researchers generally believe that the benefits of drinking milk are the main ones, and this view has the absolute upper hand. Up to now, there is no reliable scientific basis for the claim that milk is carcinogenic, but the benefits of drinking it are very clear. " Professor Wang Huaqing, director of the Cancer Diagnosis and Treatment Center of Tianjin People’s Hospital, said in an interview with the Science and Technology Daily reporter that milk and dairy products are still recommended to the public as high-quality foods in the nutritional dietary guidelines of most countries in the world.

　　Wang Huaqing believes that the key to a healthy diet lies in a balanced diet. "Simply put, it is ‘ Flower ’ Try to eat, you’d better eat more than 12 kinds of food every day and 25 kinds every week. We should not demonize a certain kind of food or deify a certain kind of food. In China’s dietary structure, residents’ calcium intake is generally insufficient. Therefore, the China Residents’ Dietary Guide (2022), which was published not long ago, recommends taking 300 ml to 500 ml of milk or corresponding dairy products every day. " He added.

　　Flammulina velutipes contains formaldehyde? Truth: The pungent smell is produced by Flammulina velutipes itself.

　　Flammulina velutipes is a popular mushroom product, but recently, there have been "popular science" articles in the circle of friends, such as "it has an odor and contains formaldehyde, and vegetable sellers never eat it themselves". According to the article, Flammulina velutipes, which is common in the vegetable market, contains formaldehyde, which not only hurts liver and kidney, but also causes cancer.

　　In this regard, Professor Ban Litong of tianjin agricultural university introduced in an interview with the Science and Technology Daily reporter that some citizens may smell pungent smell when unpacking the packaging bag of Flammulina velutipes. This is not because formaldehyde is added, but because the temperature changes during transportation, which leads to Flammulina velutipes changing from aerobic respiration to anaerobic respiration, and then some volatile aldehyde gases are produced.

　　Some netizens said that formaldehyde was added to Flammulina velutipes for bleaching. In this regard, Ban Litong introduced that Flammulina velutipes was indeed yellow, and the reason why it turned white was not the result of bleaching with formaldehyde. "Today, most of the Flammulina velutipes on the market are new varieties from Japan. Japanese researchers found white Flammulina velutipes with gene mutation in yellow Flammulina velutipes, and then kept it for cultivation. White Flammulina velutipes not only has good color, but also has fast growth speed and high uniformity. " He said.

　　According to the data, China’s Food Safety Law and Agricultural Products Quality Safety Law clearly stipulate that formaldehyde shall not be used as a food processing aid for production and operation. In other words, it is illegal to add formaldehyde to food in any way.

　　Strong chewing ability is not easy to suffer from Alzheimer’s disease? Truth: over-interpretation, there is no causal relationship between the two.

　　Alzheimer’s disease, commonly known as "Alzheimer’s disease", is a chronic progressive brain disorder caused by the damage of brain cells, which mainly affects the function of the brain, and is manifested in memory, daily living ability and other aspects. According to the current clinical data, there is no effective radical cure for this disease. However, a recent hot search in Weibo has aroused widespread concern. According to this Weibo, a study pointed out that chewing ability can predict the risk of Alzheimer’s disease, and the younger the brain, the lower the risk of Alzheimer’s disease.

　　Although chewing ability and Alzheimer’s disease seem to have nothing to do with each other, it seems that someone really found the basis of "chewing is healthier". In 2012, the American Journal of Geriatrics published a study. The study surveyed 557 elderly people aged 77 and over in Sweden. The results showed that the probability of cognitive impairment was significantly higher in people with multiple teeth falling off and hard food chewing.

　　"The above research is only an epidemiological study, which can only show that there is a correlation between masticatory ability and Alzheimer’s disease, but it can’t explain whether there is a causal relationship between them, and its mechanism needs further verification by scientific research." Zhou Yuying, chief physician of tianjin huanhu hospital Neurology Department, said in an interview with Science and Technology Daily that the exact cause of Alzheimer’s disease has not been clearly defined in the medical field, but some risk factors have been confirmed. Age is the biggest pathogenic factor of Alzheimer’s disease, and the risk of Alzheimer’s disease will increase year by year.

　　"Instead of just exercising masticatory muscles to prevent Alzheimer’s disease, it is better to start with the whole lifestyle." Zhou Yuying said, first of all, a healthy diet can control blood pressure, blood lipid and blood sugar, which will have a certain effect on preventing Alzheimer’s disease. Secondly, studies have shown that exercise is very helpful to prevent Alzheimer’s disease, such as walking and running. Hand movements, such as playing the piano, tapping the keyboard and picking up beans, can also effectively stimulate regional cerebral blood flow, which is very helpful to prevent and slow down Alzheimer’s disease.

　　Zhou Yuying said that people who lack hobbies and lead a dull life are more likely to suffer from Alzheimer’s disease, so environmental stimulation is very effective in preventing this disease. Rich life content and social circle can effectively stimulate the cerebral cortex, and "never too old to learn" can also continue to exercise the brain and prevent Alzheimer’s disease.

　　Does the negative pressure ward make it difficult for patients to breathe? Truth: The pressure difference between the inside and outside of the ward is extremely small, which will not cause any discomfort.

　　In many news reports about the COVID-19 epidemic, a word named "negative pressure ward" often appears. In the process of treating COVID-19 patients, the negative pressure ward played an important role, which can be described as a "hero" in fighting the epidemic. However, due to the lack of understanding of this kind of ward, some people only understand it from the word, and then carry out "popular science" on the Internet, saying that "negative pressure will cause patients to have difficulty breathing". What is the truth?

　　"Negative pressure ward refers to the ward where the air pressure in the ward is lower than that outside the ward, which is mainly set for patients with respiratory infectious diseases." Wang Yizhen, the chief physician of the Department of Critical Care Medicine of Tianjin TEDA Hospital, said in an interview with the Science and Technology Daily reporter that the normal atmospheric pressure is 1.013×105 Pascal (pressure unit), while the pressure difference between the negative pressure ward and the normal atmospheric pressure is only 25 Pascal. "This air pressure difference is difficult for ordinary people to detect, and patients will not feel any discomfort in the negative pressure ward."

　　Because the air pressure in the negative pressure ward is lower than the air pressure outside the ward, the air can only flow in one direction, so that when medical staff enter and leave the ward, it can ensure that fresh air from outside can flow into the ward, but the polluted air in the ward will not spread outward. The polluted air will not be discharged at will, but will be collected through special pipes and put in a fixed place, and then discharged to the outside after being filtered and disinfected layer by layer.