37 has long been considered normal body temperature in humans, and this standard body temperature dates back to the 19th century.
In 1851, a German physician named Karl Wendelich collected 2Nearly a million axillary temperature measurements for 50,000 patients, with a range of 362℃-37.5. Take its intermediate value, and finally conclude that the normal body temperature of the human body is 37, and this measurement standard is widely recognized around the world and has been used for more than 100 years.
However, in recent years, more and more studies have pointed out that in the past 100 years, the normal body temperature of human beings has been declining, what causes the human body temperature to drop, and what does the drop in body temperature mean?
1. Stanford University study: 37 is no longer the standard body temperature of the human body
Due to the epidemic, everyone took their body temperature frequently in the early two years, and if you look closely, you will find that basically the body temperature measured is 365 or so. This makes people wonder, doesn't it mean that the normal body temperature is 37?Why is my body temperature less than 37?
In fact, about the drop in human body temperature, researchers at Stanford University School of Medicine have worked in《elife》A study was published in which it was found that the standard body temperature of humans today is about, not 37 that was measured 200 years ago and is still in use today.
The study collected:A total of 677423 body temperature data from three different historical periods in the United States: Veterans with a record of service between 1862 and 1930, population temperature data from the 1971 and 1975 National Health and Nutrition Surveys, and adult data from 2007 to 2017 in the Stanford Translational Research Integrated Data Environment. The researchers used this to build a linear model that visually reflects changes in a person's body temperature.
After comparative analysis, it was found thatMales born in the 21st century are compared to the 19th centuryInitial, body temperatureDeclinenow；of the beginning of the 21st centuryFemaleCompared to the 90s of the 19th century, the body temperature has decreased。On average, human body temperature is in the following areas0. Every 10 years03℃speed inDeclineToday's average body temperature is about 366 or so.
Why does the average body temperature of modern people drop?Scientists have put forward the following speculations:
The health and dietary environment has improved substantially
The medical conditions of modern people are much better than before, and it is rare to be infected with malaria, tuberculosis and other diseases because of eating food, even if they are unfortunately infectedMedications**The chance of fever is relatively reduced, the body temperature will also drop.
With the improvement of sanitary conditions, modern peopleExposure to microbes and bad weather is also greatly reduced, in vivoImmune cellsTraining opportunities are coming and goingThe less。Many people will take strong medicine to alleviate their condition in the early stage of illness, and the body will not have the opportunity to have a fever at all, and the body temperature will become lower and lower because of this.
Living conditions have changed dramatically
Most modern people can ensure that they have enough food for three meals a day, clothing, air conditioning, heating, etcAll kinds of heating equipmentIt can ensure the body temperature. As a result, the brain's thermoregulatory center is no longer sensitive to the outside temperature, and the body's ability to generate heat will also decrease.
The amount of exercise of modern people is declining
Modern people's office environment is mostly indoors, and there is a lack of exercise every day, so the body's basal metabolic rate will decrease, and energy consumption will also decrease, which will lead to a decrease in basal body temperature.
Life is stressful
Long-term exposure to high-pressure living conditions will secrete cortisol hormones in the body to break down muscles and promote fat storage, so that the body's metabolic ability will decline and the body temperature will become lower and lower.
2. For every 1 drop in body temperature, immunity will drop by 30%.
It is rumored that the lower the body temperature of the human body, the worse the immunity, which makes many people feel scared, is there any scientific basis for this statement?
The statement comes fromJapanese MD Ishihara Yutsu365 degrees determines health", which is called body temperature in the bookEvery drop of 1Will letThe body's immunity decreases by 30%.。Conversely, for every 1 increase in body temperature in a sub-healthy state, immunity can be increased by 5 to 6 times, provided that the body temperature remains within the normal range.
In this regard,Wang Xiaochuan, deputy director of the Department of Pathophysiology, Tongji Medical College, Huazhong University of Science and TechnologyRepresentation: For nowThere is no clear research to confirm thisThe relationship between a drop or rise in body temperature and a rise or fall in immunity. ButNormal body temperature rangeIt is true that the higher the body temperature, the better the immunity. Because high body temperature can activate more immune cells, so that they can better annihilate invading foreign viruses and bacteria.
How do you think it's better to have a high or low body temperature?Professor Hu Bijie, Director of the Department of Infectious Diseases, Zhongshan Hospital, Fudan UniversityHe said that some studies have found that in the same operating room with a constant room temperature, compared with patients who use blankets and hot water bottles to maintain a body temperature above 36, patients who wear less clothes and have a body temperature lower than 35 have a greater chance of postoperative wound infection, which proves to some extent that people with high body temperature will indeed have higher immunity within the normal body temperature range.
However, I want to rely on itIt is not reliable to raise body temperature to boost immunity. Beijing Association for Science and TechnologyIt has been published that hyperthermia can easily lead to a decrease in the activity of NK cells, and will interfere with the normal physiological functions of the digestive system and nervous systemIrritability, decreased appetite, decreased ability to fight infectionsand so on.
3. Who has a stronger immune system between people with fever and those who don't?
There is a saying on the Internet that people who do not have a fever for a long time have an immune system that is not trained, and not only has poor immunity but is also more likely to develop cancer
People areConstant temperatureAnimals, normally, are called in the brainHypothalamusThe nerve centers are responsible for regulating the body's temperature and keeping body temperatureMaintained at 36 37Between. When the cells in the human body are subjectedViruses, bacteriaWhen attacking, it produces a thermogen, which allows the thermoregulatory center to move the body temperature upwards to promote heat production in tissue cellsFever
People who have not had a fever for a long time, to some extent, a reflectionGood physical fitnessWhen germs and viruses do not enter the blood circulation, they are killed by immune cells, so they will naturally not get hot, but it may also be because of daily lifeThe protective measures are betterViruses and bacteria have no chance to take advantage of them.
It is true that there are some people in life who do not have a fever for a long time, but they are found to have cancer after a check-up
People who do not have a fever for a long time may also have some minor illnesses in their daily life, such as low-grade fever, cough, etc., they will feel that it is not a problem at all, and it will pass quickly, and the people around them will naturally have no impression. When it comes to a real serious illness, there will be a clear contrast, giving people the illusion that either they are not sick or they are seriously ill. This does not mean that people who do not have a fever are susceptible to cancer, and there is no necessary connection between the two.
Nowadays, the general trend of body temperature drop, what we can do is to maintain good living habits, keep exercising, and exercise the body's thermoregulatory center as much as possible to maintain the body temperature within a relatively normal range.
References: 1] "37°C becomes history, and the standard body temperature of human beings is gradually decreasing!".》.Digital Beijing Science Center 2022-03-02
2] "37 is no longer the standard normal body temperature of the human body?".Is it better to have a low body temperature or a high temperature?》.Shangguan News 2021-09-15
3] "Who has the strongest immune system between people with fever and those who don't?".》.Health Times 2023-01-06
Permission without the author's permission is prohibited**.