What will happen to your body if you frequently soak your feet in hot water? These 4 types of people should never soak their feet in hot water!

In winter, every worker who suffers from the cold wind on the way to work probably has the same wish: to get off work early, go home and soak their feet in hot water to relieve the day's fatigue and cold.

As a health-preserving method that is as famous as "soaking wolfberries in a thermos cup", hot water foot bathing seems to be a habit that Chinese people have inherited for generations. Many people think that foot bathing can promote blood circulation throughout the body, not only help sleep, but also treat various diseases. Various foot bathing centers also use the gimmick of adding various supplements, claiming that it can strengthen the body.

But are the effects of foot soaking really that magical?

Hot water foot bath

It really helps you sleep better.

In 2013, a paper published in the International Journal of Nursing Research pointed out that according to a survey conducted from 1996 to 2005, foot soaking can indeed help sleep for healthy people.

This is because as the temperature rises, the peripheral blood vessels in the legs and feet expand, and the blood flow to the skin of the feet also increases, allowing the core area to dissipate heat better and the body to enter a sleep state better.

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However, it should be noted that for people with insomnia, foot soaking is not a permanent method of helping them sleep.

Insomnia is caused by many factors, including physiological problems such as digestive system diseases that cause internal environmental disturbances, as well as psychological problems such as excessive tension, anxiety, and even depression. Only by taking the right medicine can sleep disorders be truly alleviated.

The correct posture for foot soaking

First of all, pay attention to the temperature of the hot water, which should be around 40 degrees Celsius. Too high a temperature will damage the sebum film on the surface of the foot skin and cause cracks.

Secondly, you should also pay attention to the time of soaking your feet to prevent low-temperature burns. According to surveys, the soaking time should not exceed 30 minutes, otherwise the local circulation will be too fast, which will increase the burden on the heart. If you are using a constant temperature foot bath, it is best not to soak your feet while playing games, otherwise you will forget the time.

Most importantly, never use your feet to test the temperature. Because the skin on your feet is thicker than the skin on other parts of the body, and is far less sensitive to temperature than other human tissues, if your feet feel "just right", they may already be too hot.

Footbath is not suitable for everyone

However, foot soaking is not suitable for everyone. For some people, foot soaking can have negative effects. The following groups of people should pay more attention when soaking their feet.

1. Children

Unlike adults, children under 6 years old often have their arches not yet fully formed.

You should know that the arch of the foot is an important shock absorption system of the human body. When jumping, it can reduce the shock and reduce the impact of landing on the bones, joints and organs of the whole body. When you walk, the arch of the foot can also buffer the downward transmission of body gravity and the rebound force of the ground, so that the blood vessels and nerves in the sole of the foot are not compressed for a long time.

Soaking your feet in hot water for a long time will cause the ligaments on the plants to become loose and lack elasticity due to the heat, resulting in flat feet and other effects.

2. Patients with varicose veins or arterial occlusion

We mentioned above that soaking your feet in hot water will increase local blood flow to the feet and legs.

Varicose veins are blood vessel swellings caused by blood congestion due to venous valve insufficiency and poor venous blood return. They are more common in the front part of the limbs, such as the feet and hands.

Therefore, when patients with varicose veins soak their feet, it is equivalent to injecting more water into a stream with a closed valve. The venous return burden is further increased in this way because the stream is already crowded.

The same is true for patients with arterial occlusion. Soaking your feet for a long time will not increase blood supply and return to the lower limbs, but will only aggravate the problem.

3. Diabetic patients

According to the latest data, the number of people with diabetes in China exceeds 140 million. For diabetic patients, foot soaking is particularly important, especially for those who have already developed diabetic foot, a complication.

Most patients with diabetic foot have abnormal distal nerves in their lower limbs and varying degrees of vascular disease. Simply put, their blood vessels will not expand or contract due to temperature, and soaking their feet will not help blood circulation. On the contrary, their perception of temperature is far less sensitive than that of ordinary people. Some people may feel that water is very hot, but they may feel that it is normal. It is very easy to get burned.

Moreover, the skin on the feet of patients with diabetic foot is relatively fragile. Once burned, the consequences are much more serious than those of ordinary people. If medical treatment is not sought in time, it may even lead to foot infection and ulceration.

4. Patients with tinea pedis

Tinea pedis, also known as athlete's foot, is not just "smelly because it has been stuffy for a long time" as people imagine, but a fungal infection. Many tinea pedis patients may feel relieved temporarily after soaking their feet, and believe that hot water kills the fungus, but in fact this is just a temporary solution.

Research shows that only by boiling the fungus in 100 degrees Celsius water for 10 to 30 minutes can the fungus be inactivated and lose its pathogenicity. But the question is, who would use boiling water to soak their feet? Some people are used to testing the temperature with their feet, and they would feel extremely hot if they touched it with their toes.

On the contrary, hot water will also dilate the capillaries in the feet, thus leading to secondary bacterial infection.

“Foot soaking with medicinal herbs is more beneficial to health”?

No need to!

Many people like to add a "foot bath bag" with various medicinal materials when soaking their feet, thinking that this can make the foot soaking effect better, but it is actually completely unnecessary.

In order for drugs to really affect the human body, they must pass through the skin or hair follicles and other tissues to reach the dermis and be absorbed by the capillaries. As we all know, your feet bear most of your weight most of the time, and many elders even have thick calluses on their feet. It is extremely difficult for those nutrients to penetrate these and penetrate into the body.

A survey mentioned that the absorption rate and permeability of the soles of the feet are at the bottom compared with the scalp, back, forehead and other human tissues. It is better to drink wolfberry than to use it in a foot bath.

Foot bath bucket and foot bath bag. Copyright image library, reprinting and use may cause copyright disputes

Some people may ask, are those topical ointments useless?

Here we have to introduce a concept: the stratum corneum of the skin is a lipid membrane, and inside the stratum corneum is the active epidermis of water-based tissue. In short, only substances that are both fat-soluble and water-soluble can be absorbed by the capillaries in the dermis.

Most of those topical ointments will control the water-oil ratio or add penetration enhancers, while substances such as wolfberry are almost all water-soluble and cannot penetrate the first layer of skin barrier at all.

At the same time, soaking your feet will only allow blood to circulate locally for a short period of time and cannot directly affect the body's circulation. The merchants' claim that "hot water buckets are full of medicinal materials and soaking your feet can cure systemic diseases" is pure fantasy.

These problems with the feet

Could be a sign of disease

In fact, the fundamental reason for the misunderstanding about "foot soaking" is the lack of understanding of your feet.

In order to sell various products, many marketing accounts will create the message that "cold feet are a sign of poor health". In fact, this conclusion is not necessarily true. The human body has a temperature regulation mechanism. When it is cold, in order to maintain the temperature of the internal organs, blood will first supply other areas, so it is normal to have cold hands and feet.

However, the foot is indeed a very important organ of the human body. If the following conditions exist, it is still necessary to pay attention to it:

1. Itchy feet

If you find your feet itchy for unknown reasons and it is not the season for mosquitoes, you should consider two aspects. One is fungal infection, and the other is the precursor of diabetic foot. Neither of these can be solved by soaking your feet. You must seek medical attention in time and take the right medicine.

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2. Wear on soles

Everyone's shoes come into contact with the ground when they walk, so wear and tear is not surprising. However, when the wear area deviates from the center of the forefoot and the outside of the heel, and the degree of wear is asymmetrical, it may mean that there is a problem with your feet.

If the outer side of the forefoot and the outer side of the heel are worn more, it may be a high arch foot, that is, a high longitudinal arch of the foot. Try to think of something embarrassing. If you arch your foot, is the outer side of the foot in contact with the ground the most? If it is the opposite, it may be a flat foot, with the sole of the foot completely flat on the ground, causing inversion of the foot.

Of course, if you find that the wear on the soles is asymmetrical, if you exclude the factor of not walking properly, it is likely that you have leg dysplasia. This must be taken seriously. Whether it is structural leg dysplasia (referring to the difference in length of the two legs due to congenital inheritance or acquired injury) or functional leg dysplasia (referring to the absolute length of the two legs being basically the same, but the leg dysplasia is caused by problems such as the pelvis and arch of the foot), it will cause imbalance in the force on the lower limbs. This is not something that can be solved by Zhao Benshan coming and fooling around. You still need to seek medical attention in time.

In short, the prerequisite for scientific foot soaking is to scientifically understand your physical condition and treat your feet properly.

References

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[6] HuQ, ZhuW, ZhuY, ZhengL. Acuteeffectsofwarmfootbatharterialstiffnessinhealthyyoungandolderwomen.EurJApplPhysiol.2012Apr;112(4):1261-8.

[7] Diagnosis and treatment of tinea pedis in China: Expert consensus of the Mycology Group of the Dermatology Branch of the Chinese Medical Doctor Association. Journal of Clinical Dermatology (04), 270-271.

[8] Liu Yanfeng, Zhou Xiang, & Wang Lijuan. (2014). Preliminary study on the characteristics of human skin temperature adaptability and vertical distribution. Journal of Environment and Health, 31

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[10] China Sleep Research Society. (2022). China Sleep Big Data Report.

This article is a work of Science Popularization China-Starry Sky Project

Produced by: Science Popularization Department of China Association for Science and Technology

Producer｜China Science and Technology Press Co., Ltd., Beijing Zhongke Xinghe Culture Media Co., Ltd.

Author: Li Mi, popular science creator

Reviewer: Tang Qin, Director and Researcher of the Science Popularization Department of the Chinese Medical Association