Enoki mushrooms contain formaldehyde? Drinking milk causes cancer? Take stock of the May holiday science one by one

【Refute rumors】

Health-related news is emerging on the Internet, but the true and false "popular science" makes it difficult to distinguish
.
They may come from the "alternative" interpretation of a netizen, such as negative pressure wards that make it difficult for patients to breathe; Or the "warm tips" circulating in the circle of friends, such as enoki mushrooms containing formaldehyde; Or "research results" from professional journals, such as strong chewing ability is not easy to suffer from Alzheimer's disease, drinking milk causes cancer.
.
.

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

Drinking milk causes cancer? Truth: Without reliable science, milk is still a healthy food

The saying that "milk and dairy products cause cancer" has been widely circulated among the people, and a paper entitled "Chinese adult dairy intake is associated with cancer risk" seems to give this statement "scientific" support
.

The study, which was conducted on Chinese cohorts, followed 500,000 Chinese for 11 years
.
Relevant research data show a significant positive correlation between dairy intake and cancer risk – people who regularly consume 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 drinking milk causes cancer"
.

"There have been studies on 'whether milk causes cancer' in academic circles at home and abroad, and researchers generally believe that the benefits of drinking milk to the human body are the main one, and this view has the absolute upper hand
.
" So far, there is no reliable scientific basis for the claim that milk causes cancer, but the benefits of drinking it are clear
.
Professor Wang Huaqing, director of the Cancer Diagnosis and Treatment Center of Tianjin People's Hospital, said in an interview with a reporter from Science and Technology Daily 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 is a balanced diet
.
"To put it simply, it is best to eat more than 12 kinds of food every day and 25 kinds a
week.
Let's not demonize or deify a certain type of food
.
In China's dietary structure, the calcium intake of residents is generally insufficient, so the "Dietary Guidelines for Chinese Residents (2022)" that came out not long ago recommends a daily intake of 300 ml to 500 ml of milk or corresponding dairy products
.
He added
.

Enoki mushrooms contain formaldehyde? Truth: The pungent smell is produced by enoki mushrooms themselves

Enoki mushrooms are popular mushroom products, but recently there have been "popular science" articles
such as "it has a peculiar smell, contains formaldehyde, and vegetable sellers never eat it" in the circle of friends.
The article said that the enoki mushroom, which is common in the vegetable market, contains formaldehyde, which not only harms the liver and kidneys but also causes cancer
.

In this regard, Professor Ban Litong of Tianjin Agricultural College introduced in an interview with a reporter from Science and Technology Daily that some citizens may smell a pungent smell when opening the enoki packaging bag, which is not due to the addition of formaldehyde, but because of the temperature change during transportation, resulting in enoki mushrooms from aerobic respiration to anaerobic respiration, which in turn produces some volatile aldehyde gases
.

Some netizens said that adding formaldehyde to enoki mushrooms is for bleaching
.
In this regard, Ban Litong introduced that enoki mushrooms were indeed yellow, and the reason why they turned white was not the result of
bleaching with formaldehyde.
"Today, most of the enoki mushrooms on the market are new varieties of Japanese origin
.
Japanese researchers found the genetically mutated white enoki mushroom in the yellow enoki mushroom, and then kept it for cultivation
.
White enoki mushrooms not only have good color, but also grow fast and have high
neatness.
He said
.

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

Is chewing 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 damage to brain cells, which mainly affects the function of the brain, manifested as memory, daily living ability and other disorders
.
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 Weibo, a study pointed out that the risk of Alzheimer's disease can be predicted by chewing ability, and the younger the brain of the person with the ability to chew, the lower
the risk of Alzheimer's disease.

Although chewing ability and Alzheimer's disease may seem incompatible, it seems that someone has really found a basis
for "chewing healthier".
In 2012, a study
was published in the American Journal of Geriatrics.
The study, which surveyed 557 people aged 77 and over in Sweden, found that cognitive impairment was significantly higher
among people with multiple teeth falling out and difficulty chewing hard foods.

"The above study is only an epidemiological study, which can only show a correlation between chewing ability and Alzheimer's disease, but it cannot be said whether there is a causal relationship between the two, and its mechanism needs to be further verified
by scientific research.
" Zhou Yuying, chief physician of the Department of Neurology of Tianjin Huanhu Hospital, said in an interview with a reporter from Science and Technology Daily that the medical community has not yet identified the exact cause of Alzheimer's disease, but some risk factors have been confirmed
.
Increasing age is the biggest causative factor of Alzheimer's disease, and the risk of disease increases year by year with age
.

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

Zhou Yuying said that people who lack hobbies and have a boring and monotonous 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, "live to be old, learn to be old" can also continue to exercise the brain and prevent Alzheimer's disease
.

Can a negative pressure ward make it difficult for patients to breathe? Truth: The pressure difference between inside and outside the ward is extremely small and does not cause any discomfort

In many news reports involving the new crown pneumonia epidemic, a term
called "negative pressure ward" often appears.
In the process of treating new crown pneumonia patients, the negative pressure ward has played an important role and can be described as a "hero"
in the fight against the epidemic.
However, because of the lack of understanding of such wards, some people only understand it literally, so they conduct "science popularization" online, saying that "negative pressure will cause patients to have difficulty breathing"
.
What are the facts?

"A negative pressure ward is a ward where the air pressure in the ward is lower than the air pressure outside the
ward, which is mainly set up for patients with respiratory infectious diseases.
" Wang Yimin, chief physician of the Department of Critical Care Medicine of Tianjin TEDA Hospital, said in an interview with a reporter from Science and Technology Daily that the conventional atmospheric pressure is 1.
013×105 Pascals (pressure), while the barometric pressure difference
between the air pressure of the negative pressure ward and the conventional atmospheric pressure is only 25 Pascals.
"This difference in air pressure is difficult for ordinary people to detect, and patients will not feel any discomfort
in the negative pressure ward.
"

Since 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 exit the ward, it can ensure that fresh air from the 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 collected through special pipelines and discharged to a fixed place, and then discharged to the outside world after layers of filtration and disinfection
.

(Chen Xi)