[refute the rumor] Online health-related news emerge in endlessly, but the true and false "popular science" is difficult to distinguish. They may come from the "alternative" interpretation of a netizen. For example, the negative pressure ward will make patients have difficulty breathing; Or "warm tips" spread in the circle of friends, such as Flammulina velutipes containing formaldehyde; Or "research results" from professional journals, such as strong chewing ability, not prone to Alzheimer's disease, drinking milk and cancer Today, the reporter of science and Technology Daily will make an inventory of these false popular science rumors in may one by one to help you get rid of the fog and find the truth. Drinking milk causes cancer? Truth: milk is still a healthy food without reliable scientific basis The saying that "milk and dairy products cause cancer" has been widely spread among the people. A recent paper entitled "the intake of dairy products in Chinese adults is related to cancer risk" seems to have "scientific" evidence for this saying. The study is aimed at the Chinese population. It has followed 500000 Chinese people for 11 years. Relevant research data show that there is a significant positive correlation between dairy intake and cancer risk - people who often eat dairy products have a higher overall risk of cancer. At the same time, the above research data also pointed out the health benefits of drinking milk, such as promoting growth and development, but it seems that many netizens only care about "Chinese people drinking milk causes cancer". "There have been studies on 'whether milk causes cancer' in academic circles at home and abroad. Researchers generally believe that the benefits of drinking milk to the human body are the main, and this view has the absolute upper hand. So far, there is no reliable scientific basis for the claim of milk causing cancer, but the benefits of drinking it are very clear." Professor Wang Huaqing, director of tumor diagnosis and treatment center of Tianjin People's Hospital, said in an interview with science and Technology Daily that therefore, in the nutritional dietary guidelines of most countries in the world, milk and dairy products are still recommended to the public as high-quality food. Wang Huaqing believes that the key to a healthy diet is a balanced diet. "To put it simply, it is better to eat more than 12 kinds of food a day and 25 kinds a week. We should not demonize or deify a certain kind of food. In China's dietary structure, residents' calcium intake is generally insufficient. Therefore, the recently published dietary guide for Chinese residents (2022) recommends consuming 300 ml to 500 ml of milk or corresponding dairy products a 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 from the circle of friends, such as "it has peculiar smell and contains formaldehyde, and vegetable dealers never eat it themselves". The article said that the common Flammulina velutipes in the vegetable market contains formaldehyde, which not only hurts the liver and kidney, but also causes cancer. In this regard, ban Litong, a professor of Tianjin Agricultural College, introduced in an interview with the reporter of science and Technology Daily that some citizens may smell a pungent smell when opening the Flammulina velutipes packaging bag. This is not due to the addition of formaldehyde, but because the temperature changes during transportation, which leads to the Flammulina velutipes from aerobic breathing to anaerobic breathing, resulting in some volatile aldehyde gases. Some netizens said that adding formaldehyde to Flammulina velutipes is for bleaching. In this regard, ban Litong introduced that Flammulina velutipes was indeed yellow. The reason why it turned white was not the result of bleaching with formaldehyde. "Nowadays, most of the Flammulina velutipes on the market are new varieties from Japan. Japanese researchers found the mutated White Flammulina velutipes in the Yellow Flammulina velutipes, and then kept it for cultivation. The White Flammulina velutipes not only has good color, but also has fast growth speed and high uniformity." He said. The data shows that the food safety law and the agricultural product quality safety law clearly stipulate that formaldehyde shall not be used as food processing aids for production and operation. In other words, it is illegal to add formaldehyde to food in any way. Strong masticatory ability, not prone to 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. It mainly affects the function of the brain and is manifested in the impairment of memory, daily living ability and so on. According to the current clinical data, there is no effective radical cure for this disease. However, a recent hot search on Weibo has attracted widespread attention. According to the microblog, a study pointed out that chewing ability can predict the risk of Alzheimer's disease. The younger the brain of people with stronger chewing ability, the lower the risk of Alzheimer's disease. Although chewing ability and Alzheimer's disease seem different, it seems that someone has really found the basis for "chewing is healthier". In 2012, the American Journal of geriatrics published a study. The study surveyed 557 people aged 77 and over in Sweden and found that people with multiple teeth falling out and difficulty chewing hard food were significantly more likely to have cognitive impairment. "The above study is only an epidemiological study, which can only show that there is a correlation between chewing ability and Alzheimer's disease, but it can not explain whether there is a causal relationship between the two. The mechanism needs to be further verified by scientific research." Zhou Yuying, chief physician of Neurology Department of Tianjin Huanhu hospital, said in an interview with science and Technology Daily that at present, the medical community has not determined the exact cause of Alzheimer's disease, but some risk factors have been confirmed. Age is the biggest pathogenic factor of Alzheimer's disease, and the risk will increase year by year with age. "Instead of just exercising masticatory muscles to prevent Alzheimer's disease, it's better to start with the whole lifestyle." Zhou Yuying said that first of all, a healthy diet can control blood pressure, blood lipid and blood glucose, which will have a certain effect on the prevention of Alzheimer's disease. Secondly, studies have shown that exercise is very helpful to prevent Alzheimer's disease, such as walking, running and so on. 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 interests and hobbies and live a boring and monotonous life are more likely to suffer from Alzheimer's disease, so environmental stimulation is very effective in preventing the disease. Rich life content and social circles can effectively stimulate the cerebral cortex, and "never too old to learn" can also continue to exercise the brain and prevent Alzheimer's disease. Can negative pressure ward make patients have difficulty breathing? Truth: the pressure difference inside and outside the ward is very small and will not cause any discomfort In many news reports about the COVID-19, the word "negative pressure ward" often appears. In the process of treating patients with COVID-19, the negative pressure ward has played an important role and can be described as a "hero" of anti epidemic. However, due to the lack of understanding of such wards, some people only understand them from the word, so they "popularize science" on the Internet, saying that "negative pressure will cause patients to have difficulty breathing". What are the facts? "Negative pressure ward refers to the ward where the air pressure in the ward is lower than that outside the ward. It is mainly set up for patients with respiratory infectious diseases." Wang Yimin, chief physician of Critical Medicine Department of Tianjin TEDA hospital, said in an interview with science and Technology Daily that the conventional atmospheric pressure is 1.013 × 105 Pascal (pressure unit), while the pressure difference between the negative pressure ward and the conventional 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 that outside the ward, the air can only flow in one direction. In this way, when the medical staff enter and leave the ward, it can ensure that the external fresh air 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 discharged to a fixed place, and then discharged to the outside after layer by layer filtration and disinfection. (outlook new era)