July 2022 "Science" Rumor List: Heat stroke only occurs outdoors? Wearing a mask causes lung nodules to grow larger?

The July 2022 "Science" Rumor List is Announced!

Does heat stroke only occur outdoors? Can wearing a mask for a long time cause lung nodules to grow? Does ice cream melt slowly because it has glue? Let's see the truth.

The monthly "science" rumor list is guided by the Beijing Association for Science and Technology, the Beijing Municipal Cyberspace Administration, and the Capital Internet Association, and jointly released by the Beijing Science and Technology Journalists and Editors Association and the Beijing Regional Website Joint Rumor-Refuting Platform, and is supported by the Science and Technology Journalists and Editors Professional Committee of the China Science Writers Association, the China Evening News Science Editors and Journalists Association, the Shanghai Science Communication Association, and the Institute of Science and Technology Information of the Beijing Academy of Science and Technology.

1. Heat stroke only happens outdoors

gossip:

Heat stroke is caused by excessive exposure to sunlight and only occurs outdoors, so you don't have to worry as long as you stay indoors.

the truth:

Heat stroke is not exclusive to the outdoors. In summer, high temperatures outdoors and stuffy indoor temperatures and lack of ventilation can all cause heat stroke.

Heat stroke is the most serious of the heat-related emergencies, namely severe heat stroke. It is caused by the imbalance of the body's regulatory function when exposed to high temperature and high humidity, and the heat production is greater than the heat dissipation, which leads to a rapid increase in core temperature of more than 40°C, accompanied by burning skin, impaired consciousness (such as delirium, convulsions, coma) and multiple organ dysfunction. It is a serious and fatal disease. It is the most serious type of heat stroke. Once it occurs, the mortality rate is extremely high. According to the cause of the disease and the susceptible population, heat stroke can be divided into non-exertional heat stroke (also known as classic heat stroke) and exertional heat stroke. The former is common in young people, pregnant women and the elderly, while the latter is common in people who exercise vigorously in summer and those who engage in high-intensity physical activities. A considerable number of these high-intensity physical laborers are workers, including outdoor workers such as construction workers and sanitation workers, as well as indoor workers such as decoration workers and workshop workers.

Although it is possible to get heat stroke indoors, outdoor workers are at a higher risk of worsening heat stroke than indoor workers. According to relevant studies, outdoor patients are more likely to have their condition worsen than indoor patients. After treatment, more than 80% of outdoor heat stroke patients eventually died or could not recover consciousness. In terms of exposure time, the average exposure time (high temperature and high humidity environment) of outdoor patients is 2.3 hours less than that of indoor patients.

The key to reducing the mortality rate of heat stroke is prevention. The most effective preventive measures are to avoid high temperature (high humidity) and poorly ventilated environments, reduce and avoid risk factors for heat stroke, ensure adequate rest time, and avoid dehydration, thereby reducing the incidence and mortality of heat stroke.

2. Wearing a mask for a long time can cause lung nodules to grow larger

gossip:

The meltblown fabric in the middle layer of the mask is a petroleum product. The tiny particles in it can enter the human lungs through the respiratory tract. Long-term wearing will cause the lung nodules to enlarge.

the truth:

When a mask is worn within its normal period of use, it will not produce any particles, nor will it cause the enlargement of lung nodules.

In addition to textile materials such as cotton, wool, linen, silk, and regenerated cellulose fibers, many synthetic fibers, including meltblown fabrics, are made from petroleum-based materials. Polypropylene, as the main petroleum-based material, has a very wide range of applications. The meltblown fabric used to make masks is an ultra-fine fiber nonwoven material made from polypropylene polymer materials.

After being processed into meltblown cloth, this polymer material has a certain strength and very good filtering performance. As long as it is not exposed to the sun and does not exceed the service life, it will not produce fine particles.

3. You won’t get fatty liver if you only eat vegetarian food

gossip:

Since eating too much meat can easily lead to fatty liver, sticking to a vegetarian diet can help you avoid the disease.

the truth:

Eating too much meat can indeed lead to fatty liver, but it is not only eating too much meat that can lead to fatty liver. Even eating only vegetarian food can lead to fatty liver. In contrast to overnutrition-type fatty liver, long-term malnutrition and lack of protein intake can lead to "nutrition-deficiency-type fatty liver."

Long-term vegetarians may suffer from protein deficiency due to unbalanced nutrition. The liver needs protein to transport fat, so this will cause fat transport obstacles and cause fat to accumulate in the liver.

In addition, compared with people who eat a balanced diet, vegetarians tend to feel hungry more easily, and the human digestive system will stimulate the body to eat more carbohydrates such as white rice, bread, and biscuits to increase satiety. These carbohydrates have a lot of calories, which can be converted into fat and stored in the liver, increasing the risk of fatty liver disease. In addition, excessive drinking may also lead to alcoholic fatty liver. Therefore, eating greasy food and eating a lot of meat are not the only factors that lead to fatty liver.

4. Stop using the meat grinder, otherwise it will damage the liver

gossip:

Doctors recommend stopping the use of meat grinders, as this can damage the liver. If the meat grinder is not cleaned properly, it will become moldy and produce aflatoxin, which can damage the liver and cause cancer.

the truth:

This statement is alarmist. Aflatoxin is indeed very toxic and consuming a certain amount may cause liver damage, but meat is not a food that is easily contaminated by aflatoxin. As long as you pay attention to hygienic operation when using a meat grinder in daily life, there will be no safety issues.

According to the results of global food safety risk assessment, aflatoxin mainly contaminates grains, nuts and seeds, as well as milk and other foods. Among them, corn and peanuts are the most common and serious contamination, mainly because grains and other foods are infected by toxin-producing fungi such as aflatoxin before being harvested in the field and produce toxins. So far, there have been no cases of meat poisoning caused by aflatoxin contamination.

5. Ice cream melts slowly because it contains toxic glue

gossip:

A certain brand of ice cream did not completely melt even after being left at around 31 degrees Celsius for an hour. This is because it contains "glue" (thickener). If consumed in excess, it can cause gastrointestinal diseases and even affect the development of children's nervous system.

the truth:

There are many factors that affect the melting speed of ice cream, mainly related to the ingredients. Ice cream left at 31°C for one hour will definitely melt, but because the protein and thickener (soluble fiber) in the dry matter of ice cream are large molecules, they can form a scaffold-like spatial structure, so it can help it maintain its "shape" after melting.

Thickeners are very common in popsicles and ice creams. Their main function is to change the ice crystal structure and form a soft texture. Thickeners can also enhance the stability of the product texture and slow down the melting rate. As long as they are added properly, there is no need to worry.

Among the thickeners currently approved for use by the state, there are about 20 with the word "glue" in their name, of which the majority are from plants (especially leguminous plant seeds). The majority of these "glue" ingredients are "polysaccharides" and "soluble dietary fiber" that are beneficial to health. However, it is not enough for these "glue" manufacturers to add a little more, because if too much is added, it will not be ice cream/ice cream, but jelly, so "long-term large quantities" and "excessive intake" are not realistic.

6. Sitting on a hot stone block can cure dysmenorrhea

gossip:

High-temperature stone pillars can be used to treat dysmenorrhea. Just sit on a stone pillar exposed to the sun and the dysmenorrhea will be relieved immediately.

the truth:

Sitting on a hot stone block cannot cure dysmenorrhea. Some people feel that their symptoms are relieved after sitting on a hot stone block. On the one hand, it is because the stone block is very hot, which may affect the body's senses and thus divert attention from dysmenorrhea; on the other hand, sitting on a hot stone block may improve the local blood circulation of the body to a certain extent, so that the local prostaglandin level decreases with blood circulation, which is similar to the principle of a heat pad or a hot water bottle.

However, the surface temperature of the stone pier can reach 60-70 degrees Celsius after being exposed to the sun. Sitting on the stone pier for a long time may cause burns, so it is not recommended to try.

7. Looking up to play with your phone can prevent cervical spondylosis

gossip:

Keeping your head down for a long time is not good for your cervical spine, so you can tilt your head back when playing with your phone in bed, which can relieve the pressure on your cervical spine.

the truth:

Many people feel uncomfortable after working with their heads down for a long time, and they often consciously pay extra attention to their necks in the hope that the discomfort or pain will be relieved. However, the pressure on the cervical spine from looking up or looking down for a long time is similar, just in different directions.

So, how to protect the cervical spine scientifically? First of all, you can move your neck appropriately, exercise the strength of your neck muscles, try to maintain a good sitting posture when working, keep the cervical spine in a neutral position, and do not overuse it. Secondly, if you have symptoms of cervical spondylosis, you should seek medical attention in time. If the symptoms cannot be relieved by non-surgical treatment within three months, you need to consider surgical treatment. Although there are certain risks in surgery, cervical spondylosis surgery is minimally invasive and the medical technology is relatively mature. It can directly relieve nerve compression and fundamentally solve the problem. If it has reached the point where surgery is needed, the sooner you undergo surgery, the better the recovery effect will be.

8. Straight and long bananas are injected with hormones and cannot be eaten

gossip:

Don't buy straight and long bananas, as they may be "hormone bananas" that have been grown and ripened prematurely and treated with chemicals. Round and curved bananas are naturally ripe.

the truth:

There are many types of bananas, and the fruit shapes are also different. Most bananas are crescent-shaped or half-crescent-shaped. Plantains and red bananas are straighter, while pink bananas are slightly curved. The straightness or curvature of bananas is also related to the position of the banana and the growing season. In other words, there is no scientific basis for simply relying on the straightness or curvature of bananas to identify whether they are edible.

Bananas are subtropical fruits. Freshly picked bananas are hard in texture and can only be sold and eaten after a period of storage and ripening. However, if they are left to ripen on their own, it will take a long time, the ripening will be uneven, and the fruit stalk and fruit axis will be easily rotten. Therefore, bananas must be artificially ripened after being harvested, which can not only shorten the period of bananas being put on the market after being harvested, but also help improve the quality of the fruit.

There are many ways to ripen bananas, among which ethephon is widely used because of its safety, convenience and high efficiency. Ethephon is a common plant growth regulator currently sold and used in the market. The structure and function of plant growth regulators are different from animal "hormones". They mainly act on plant cells and will not have negative effects on human growth and development.

With the promotion and application of modern agricultural technology, preservatives, food additives and plant growth regulators are not harmful to human health as long as they are allowed to be used in accordance with relevant national standards and at the prescribed dosage.

9. Blood pressure drops in summer, indicating that hypertension is gradually being cured

gossip:

After the summer, some patients with hypertension unexpectedly found that their blood pressure had dropped and even reached normal levels, indicating that their hypertension had been "cured".

the truth:

In the hot summer, the blood vessels of the human body expand, and the peripheral vascular resistance decreases, which leads to a drop in blood pressure. In addition, in a high temperature environment, the human body sweats more, drinks less water, and has a reduced blood volume and a decreased cardiac output, which can easily lead to a drop in blood pressure. Therefore, the blood pressure of many hypertensive patients in the summer seems to reach normal levels, not because the hypertension is really "cured".

It should be noted that "normal" blood pressure in summer does not mean that you can stop taking medication. Blood pressure measurements are usually taken during the day, and the hot weather in summer causes many people to have poor sleep quality at night, which can affect the regulation of the neuroendocrine system, increase blood pressure at night, and lead to large changes in blood pressure during the day and night, which in turn increases the risk of myocardial ischemia and stroke.

Therefore, the blood pressure situation cannot be judged solely based on the results of daytime measurements. 24-hour blood pressure monitoring and other necessary examinations are required. Hypertensive patients need to use medications in a standardized manner under the guidance of a doctor, reduce the dosage as appropriate, and must not stop taking antihypertensive drugs without authorization.

10. Get a rabies vaccine once, and you don’t need to get another one within two years

gossip:

The rabies vaccine is effective once and lasts for two years. After taking the vaccine once, you don’t have to worry about rabies if you are bitten by an animal within two years.

the truth:

This is a misunderstanding. Rabies vaccine does not complete the entire course of immunity with just one injection, so don't take chances.

Rabies is the infectious disease with the highest mortality rate in the world, with about 59,000 deaths per year. If not properly treated after exposure, once clinical symptoms appear, the mortality rate is almost 100%, so it should not be taken lightly.

If you are bitten by a dog after vaccination, you should handle it according to different situations. According to the "Technical Guidelines for Rabies Prevention and Control (2016 Edition)", if the re-exposure occurs during the vaccination process, continue to complete the full vaccination according to the original procedure, and there is no need to increase the dose; if you are exposed again within six months after the full vaccination, you generally do not need to be vaccinated again; if you are exposed again within six months to one year after the full vaccination, you should receive 1 dose of vaccine on days 0 and 3; if you are exposed again within 1-3 years, you should receive 1 dose of vaccine on days 0, 3, and 7; if you are exposed again for more than 3 years, you should receive the full vaccination.

11. Don’t flush toilet paper directly

gossip:

After using the toilet, you cannot throw the toilet paper directly into the toilet and flush it away, otherwise it will cause serious consequences such as blockage.

the truth:

Whether you can flush toilet paper down the toilet depends on what paper you use. In most cases, you can flush toilet paper down the toilet.

Historically, horse manure paper and wrinkled toilet paper were widely used. The raw materials were varied and the workmanship was relatively rough. The paper fibers were thick and strong. If you throw them directly into the toilet, it is indeed easy to clog. Therefore, the small wastebasket in the bathroom in the past did play the role of "guarding" the toilet.

The commonly used toilet paper rolls today are easily "broken into pieces" under the impact of water flow. The national standard for toilet paper GB/T 20810-2018 "Toilet Paper (including toilet paper base paper)" currently being implemented also has a test on the dispersibility of paper. Basically, a certain amount of paper is put into a plum blossom tube filled with 5 liters of water, and then rotated and ventilated. The paper is qualified only if it breaks within 40 seconds. Therefore, toilet paper that meets the relevant standards can be flushed away directly without putting too much pressure on the toilet.

But other types of paper may not be suitable for toilets. For example, tissue paper and paper towels are often thicker and more flexible. This is usually because the fibers used in this type of paper are longer and contain ingredients that can maintain strength after being soaked in water. In addition, kitchen paper towels and chemical fiber non-woven fabrics must not fall apart or break when wet. Throwing such "paper" in the toilet will really "add to the clog".

On the other hand, the toilet and pipes are also important factors that affect whether flushing can be done. Today's flush toilets are quite powerful, and the pipes are usually thicker, so there is no problem with toilet paper. But if it is an old bathroom, the toilet may have weak flushing power, and the pipes may have become narrower and rougher due to sedimentation and corrosion. In this case, flushing directly may also have hidden dangers.

(Sources of this issue: The Paper, "Healthy China" WeChat public account, Beijing Science and Technology News, Qianlong.com, "Dietary Reference" WeChat public account, Tencent Jiuzhen, Science Popularization China, Beijing Xuanwu Hospital, "Healthy Beijing" WeChat public account, Yangcheng Evening News, Science Refutes Rumors)

Produced by: Science Central Kitchen

Produced by: Beijing Science and Technology News | Beijing Science and Technology Media

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