In winter, every migrant worker who has been devastated by the cold wind on the commute probably has the same wish: to leave work early and go home to soak their feet in hot water to relieve the fatigue and cold of the day.
As a health regimen with the same name as "soaking goji berries in a thermos cup", hot water foot soaking seems to be a Xi habit that Chinese have followed for several generations, and many people feel that foot soaking can promote blood circulation throughout the body, not only can help sleep, but also treat various diseases. Various foot baths also use the addition of various supplements as a gimmick, claiming that they can strengthen the body.
But is the effect of foot soaking really so magical?
Soak your feet in hot water
It is true that you can sleep more soundly
In 2013, a paper published in the International Journal of Nursing Research pointed out that, according to a study conducted from 1996 to 2005, foot soaking can indeed help sleep in healthy people.
This is because as the temperature rises, the peripheral blood vessels in the legs and feet dilate, and the blood flow to the skin of the feet will also increase, allowing the core area to better dissipate heat and the body to better enter the state of sleep.
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However, it should be noted that for people with insomnia, foot soaking is not a one-time sleep aid.
Insomnia is caused by many factors, in addition to physical problems such as digestive disorders that can cause disorders in the internal environment, there are also psychological problems such as emotional overtension, anxiety and even depression. Only by prescribing the right medicine can you really alleviate sleep disorders.
The correct posture for foot soaking
First of all, pay attention to the temperature of the hot water, about 40 degrees Celsius, too high will damage the sebum film on the surface of the skin of the feet, causing chapping.
Secondly, you should also pay attention to the time of foot soaking to prevent low-temperature burns. According to the survey, the foot soaking time should not exceed 30 minutes, otherwise the local circulation is too fast, which will increase the burden on the heart. If you're using a thermostatic foot soaking bucket, it's best not to soak your feet while playing games, as this will lose track of time.
Most importantly, never test the temperature with your feet. Because the skin of the feet is thicker than the skin in other places, the sensitivity to temperature is far less than that of other human tissues, and the feet feel "just right", perhaps they are already hot.
Not everyone is suitable for foot soaking
However, not everyone is suitable for foot soaking. For some people, foot soaking will bring negative effects, and the following groups of people should pay more attention when soaking their feet.
child
Unlike adults, children before the age of 6 often have not fully developed the arch of their feet.
It is important to know that the arch of the foot is an important shock absorbing system of the human body. When doing a jumping action, it can slow down the shock and reduce the impact of landing on the bones and joints of the whole body and human organs. When you walk, the arch of the foot also cushions the downward gravity of the body and the rebound of the ground, so that the blood vessels and nerves in the plantar of the foot are not compressed for a long time.
Soaking your feet in hot water for a long time will make the plantar ligaments relax when exposed to heat and lack elasticity, resulting in flat feet and other effects.
Patients with varicose veins or arterial occlusion
As we mentioned above, soaking your feet in hot water increases local blood flow to your feet and legs.
Varicose veins are blood stasis angiomatas caused by venous valve insufficiency and poor venous blood return, which are more common in the anterior segments of the limbs, that is, the feet and hands.
Therefore, soaking the feet of a varicose vein patient is equivalent to injecting some more water into a stream with a closed valve. It is already crowded, which makes the burden of venous return even heavier.
The same is true for patients with arterial occlusion, and soaking the feet for a long time will not increase the supply and return of blood to the lower limbs, but will only make the problem worse.
Diabetics
According to the latest data, there are more than 140 million people with diabetes in China. For diabetics, foot soaking is especially important. This is especially true for people who already have diabetic foot, a complication.
Most patients with diabetic foot have nerve abnormalities in the distal lower extremities and varying degrees of vascular disease. To put it simply, their blood vessels do not expand or contract due to the temperature, and soaking their feet does not help blood flow. On the contrary, their perception of temperature is far less sensitive than that of ordinary people, and some people may feel that water is hot, but they may feel that it is normal. Burns are highly susceptible.
Moreover, the foot skin of diabetic foot patients is relatively fragile, and once burned, the consequences are much more serious than ordinary people, and if you do not seek medical attention in time, it can even lead to foot infection and ulceration.
Foot leper patients
Tinea pedis, also known as athlete's foot, is not just a fungal infection that people imagine "it smells like it has been stuffy for a long time". Many people with tinea pedis may feel soothing for a short time after soaking their feet, and believe that the hot water kills the fungus, but in fact, this is just drinking to quench their thirst.
Studies have shown that only boiling the fungus in water at 100 degrees Celsius for 10 to 30 minutes can inactivate the fungus and lose its pathogenicity. But the question is, who will take boiling water to soak their feet? Some people are Xi using their feet to test the temperature, and touching them with their toes is already very hot.
Conversely, hot water also dilates the capillaries in the feet, which can lead to secondary bacterial infections.
"Soaking your feet and adding medicinal herbs is more healthy"?
You don't have to!
Many people like to add a "foot bath bag" when soaking their feet, which contains various medicinal materials, thinking that this can make the effect of foot soaking better, but in fact, it is completely unnecessary.
For a drug to really affect the human body, it must pass through tissues such as skin or hair follicles to reach the dermis before it can be absorbed by capillaries. As we all know, your feet carry most of your weight most of the time, and many elders even have thick calluses on their feet. Those nutrients want to penetrate these and penetrate into the body, but it is difficult to reach the sky.
According to a survey, the absorption rate and penetration rate of the soles of the feet are the lowest compared to human tissues such as the scalp, back, and forehead. It is better to use the wolfberries in the foot soaking bucket than to drink them.
Foot bath bucket and foot bath bag. The stock copyright picture, reprinting and using may cause copyright disputes
One might ask, aren't those external ointments useless?
This leads to the concept that the stratum corneum of the skin is a lipid membrane, and the stratum corneum is the active epidermis of the aqueous tissue, in short, only the fat-soluble and water-soluble can be absorbed by the capillaries in the dermis.
Most of those external ointments will control the proportion of water and oil or add permeation enhancers, while substances such as wolfberry are almost water-soluble, and they cannot penetrate the first layer of the skin at all.
At the same time, soaking the feet will only allow the blood to circulate locally in a short period of time, and cannot directly affect the systemic circulation. The merchants' saying that "the hot water bucket is full of medicinal herbs, and soaking your feet can cure systemic diseases" is purely fantastical.
These problems occur in the feet
May be a sign of illness
In fact, the fundamental reason for the misunderstanding of "foot soaking" is that you don't know enough about your feet.
In order to sell various products, many marketing accounts will create the message that "cold feet are a sign of bad health", but in fact, this conclusion is not necessarily true. The human body has a temperature regulation mechanism, and when it is cold, in order to ensure the temperature of the internal organs, the blood will first supply other regions, so it is normal for the hands and feet to be cold.
However, the foot is indeed a very important organ of the human body, and it is still necessary to pay attention to it if there are the following situations:
Itchy feet
If you notice that your feet are itchy for no apparent reason, and this is not the season when mosquitoes are endemic, you need to consider two aspects. One is a fungal infection, and the other is a precursor to diabetic foot. Neither of these can be solved by soaking your feet, so you must seek medical attention in time and prescribe the right medicine.
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The soles are worn
It's not surprising that everyone walks with their shoes in contact with the ground, but when the wear deviates from the center of the forefoot and the outside of the heel, and the degree of wear is asymmetrical, it could mean that there is something wrong with your foot.
If the outside of the forefoot and the outside of the heel are more worn, it may be high arched feet, that is, the longitudinal arch of the foot is higher, try to think about the embarrassing thing, let the ball of the foot arch, is it the outside of the foot that touches the ground the most?
Of course, if you find that the wear of the sole is asymmetrical, if you exclude the element of not walking well, it is likely to be long and short legs. This must be paid attention to, whether it is a structural long and short leg (referring to the difference in length of the legs due to congenital heredity or acquired damage) or a functional long and short leg (referring to the absolute length of the legs is basically the same, but the long and short legs caused by the pelvis, arch and other problems), it will bring about an imbalance in the lower limbs, which is not something that Zhao Benshan can solve by flickering twice, or seek medical attention in time.
In short, the premise of scientific foot soaking is to scientifically understand your physical condition and treat your feet properly.
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Planning and production
This article is a work of popular science China-Star Project
Produced by the Department of Science and Technology of the China Association for Science and Technology
Producer: China Science and Technology Press Co., Ltd., Beijing Zhongke Galaxy Culture Media Co., Ltd
Author丨Li Mi is a popular science creator
Review丨Tang Qin, Director of the Science Popularization Department of the Chinese Medical Association, Researcher