Is it easy to lose weight when frozen? Children with severe heating radiation are prone to leukemia? Exposing the ankle leads to a clever bag?
Just after first frost, a wave of cold air hit again. Some "precautions" about winter have also spread. For example, we often hear some old experiences, such as "protecting your head and preventing colds"; Cold can activate brown fat, so wearing less in winter is easy to lose weight; A WeChat article said that heating radiation should be paid attention to in winter, which may lead to leukemia. There is also an article saying that wearing ankle-length pants in winter or getting ovarian chocolate cyst … … Are these rumors really correct?
Myth 1: Cold can activate brown fat. Wearing less is easy to lose weight.
When the weather is cold, there is less exercise, and it seems more difficult to lose weight. Recently, an article said that the researchers did experiments on mice. After putting obese mice in an environment of 5 degrees Celsius for a week, they lost an average weight of 14%. So there are rumors that cold can make people thin, right?
"This statement is not scientific." Ma Jie, director of the Center for Prevention of Diseases of Sichuan Second Hospital of Traditional Chinese Medicine, said that under the stimulation of cold, human beings will use two ways to generate heat quickly to maintain their body temperature. One is shivering to produce heat, which is commonly known as "shaking", which provides heat through the contraction of skeletal muscle. The other is non-shivering thermogenesis, also known as metabolic thermogenesis, which is mainly accomplished by lipid decomposition and oxidation in brown adipose tissue.
"Although brown fat has the effect of burning fat, it only exists in a large number of babies or small mammals, such as mice. In adults, only a small amount of brown fat remains, mainly in the neck. Therefore, it is unscientific for adults to lose weight by stimulating brown fat with cold. " Ma Jie said.
Wang Chunxiang, director of the Nutrition Department of Zhongda Hospital affiliated to Southeast University, said that although it is called "fat", the function of brown fat is more like muscle. It is responsible for decomposing white fat that causes obesity, and converting glucose and white fat into carbon dioxide, water and energy, without storing calories. Brown fat has a high thermal efficiency. A small piece of brown fat can burn a lot of calories, and even white fat stored in other parts of the body can be used as its "fuel".
"But brown fat is rarely distributed in the adult body." Wang Chunxiang said, "For adults, brown fat only exists on both sides of the neck, on the upper back, around the clavicle and spine, and around the great blood vessels." In a normal adult’s body, there is about 60 grams of brown fat, and through CT and other imaging comparisons, the distribution of brown fat in obese people is less than that in thin people, and the distribution of brown fat in men is less than that in young women.
Myth 2: Severe heating radiation can lead to childhood leukemia.
Heating can be said to be the standard in northern winter. Recently, a WeChat article said that severe heating radiation may cause children to suffer from leukemia. Is this statement correct?
Ethan, director of hematology department of the Ninth Hospital of Xi ‘an, said: "I have been a doctor for more than 20 years, and I have never met or heard that floor heating causes children to suffer from leukemia in outpatient clinics and academic conferences. At present, the pathogenesis of childhood leukemia is generally recognized as physical factors, chemicals, ionizing radiation, genetic factors and so on. Among them, ionizing radiation includes nuclear radiation, X-rays, etc. It has been medically confirmed that it can cause bone marrow suppression, cause gene mutation, and lead to leukemia, but I have never heard of the statement that floor heating causes leukemia. "
Li Jieping, deputy chief physician of the Department of Hematology, Changsha Central Hospital, said that the exact cause of leukemia has not yet been fully clarified. Many factors are thought to be related to the onset of leukemia.
"Virus may be the main factor. The leukemia effect of RNA virus on animals such as mice, cats, chickens and cows has been affirmed. Most leukemia caused by this kind of virus belongs to T cell type. The second factor is genetic factors. People with chromosomal aberrations have a higher incidence of leukemia than normal people, as well as congenital aplastic anemia, and the probability of leukemia is much higher. " Li Jieping said that in addition, radiation and radiation are also the main factors. All kinds of ionizing radiation can cause human leukemia. The occurrence of leukemia depends on the dose absorbed by the human body. The whole body or part of the body can be induced by moderate or large doses of radiation. It is still uncertain whether low doses of radiation can cause leukemia.
"Chemical poisons or drugs and other factors can also induce leukemia. Benzene and its derivatives, chloramphenicol, phenylbutazone, ethyldimorpholine, alkylating agents, cytotoxic drugs, etc. can induce leukemia, such as breast cancer, ovarian cancer and lung cancer after chemotherapy. It is also prone to secondary leukemia. In recent years, there have been many reports that indoor decoration and furniture and toy pollution are a major cause of the increase in the incidence of leukemia among urban children. " Li Jieping said.
Myth 3: Exposing your ankles and getting cold easily leads to chocolate cysts.
Exposing ankles has become a feature of young people’s dressing. Recently, an article said, please put down your trouser legs! A 16-year-old girl, for the sake of beauty, has been wearing ankle-length pants in winter, but she got ovarian chocolate cyst.
However, there is no direct evidence that there is a causal link between ankle exposure and chocolate cyst. Xiangyang, chief physician of Obstetrics and Gynecology Department of Peking Union Medical College Hospital, said that ovarian chocolate cyst, also known as ovarian endometriosis cyst, is a pathological change of endometriosis.
Under normal circumstances, the endometrium grows in the uterine cavity and falls off once a month under the influence of female hormones in the body, forming menstruation. If the fragments of endometrium shed during menstrual period enter the pelvic cavity through the fallopian tube with menstrual blood countercurrent and are planted on the surface of the ovary or other parts of the pelvic cavity, ectopic endometrium is also affected by sex hormones, and it falls off and bleeds repeatedly with menstrual cycle. For example, if the lesion occurs on the ovary, there will be local bleeding during each menstrual period, which will enlarge the ovary and form a cyst containing old hematocele, that is, "ovarian chocolate cyst".
"Because the etiology is unclear, its histology is complicated and cannot be completely prevented. According to the possible etiology and epidemiological results, prevention can be carried out from the following aspects: preventing menstrual blood reflux; Drug contraception; Prevent iatrogenic ectopic endometrial implantation. " Xiangyang said.
Zhou Wei, an attending physician of obstetrics and gynecology in Xiangtan Maternal and Child Health Hospital, also said that the cause of ovarian chocolate cyst is not clear, but it is closely related to intrauterine surgery, which is mainly induced abortion. Therefore, the implementation of contraceptive measures and the elimination of induced abortion are helpful to prevent the occurrence of ovarian chocolate cysts.
Myth 4: It is easy to catch a cold without wearing a hat at most.
In winter, we often hear some old experiences, such as "protecting your head against colds". It is rumored that in winter, your head loses the most heat, and if you go out without a hat, you will obviously get colds and other diseases. Is this true?
"For adults, there is no necessary connection between wearing a hat and catching a cold. Wearing a hat has two functions, one is to prevent the head from catching cold, and the other is to prevent the sun from drying, which is not necessarily related to colds. " Zhang Xuan, the attending physician of the Affiliated Hospital of Zunyi Medical College, said that for children, the baby’s physique will not be affected by wearing a hat or not.
According to a survey made by American Pediatrician magazine, about 40%— 50% parents believe that low temperature will make their children catch a cold. However, according to the American Academy of Pediatrics, colds are common in cold weather because children will stay indoors more and have closer contact with other students at that time, which provides a more convenient channel for the spread of the virus.
The saying that "the head has more heat dissipation" can be traced back to the 1850s. The U.S. Army decided to conduct several tests in extremely cold conditions and then measure the heat lost from the body. The soldiers wore the latest polar survival equipment all over, but they didn’t wear hats. Later, the experiment found that the head did lose a considerable part of the body heat, but in this case of being fully armed and not wearing a hat, of course, the human body must first lose most of the heat through the head. So American Army scientists concluded that 40% of the human body & mdash; 45% of the heat is lost through the head.
However, according to an article published in the British Medical Journal, researchers from the Health Policy Center of Indiana University said, "If ‘ The head loses the most heat ’ The statement is really correct, then a person who goes out without a hat will obviously be as cold as a person who goes out without trousers, but we all know that this is obviously not the case. "
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