Skin scaling and itching may be due to not taking a bath
Today, Xiaohan officially enters the "March 9" this Saturday.
As the temperature drops, skin problems of varying degrees such as dryness, desquamation, and itching also follow one after another.
But many people don't know that most of these skin problems are directly or indirectly related to bathing.
Today, let’s talk about how to take care of the skin in winter, especially the seemingly ordinary bathing. In fact, there are many misunderstandings.
Why are there so many skin problems in winter
In the north, the three factors of cold weather, dry climate and indoor heating can cause skin problems such as desquamation and itching.
Why is this?
In fact, there are a series of "moisturizing molecules" on the surface of healthy skin (including natural moisturizing factor NMF, glycerides, lipid molecules, etc.).
These moisturizing molecules can lock the moisture in the skin, build a normal skin lipid formation structure, and maintain the epidermal barrier function.
At the same time, a series of normal flora is colonized on the surface of healthy skin. These normal flora can form ecological competition with pathogenic microorganisms to protect the skin from infection.
Bathing, especially hot water bathing, will wash away the "moisturizing molecules" and colonizing microorganisms on the skin's surface while cleaning.
In summer, due to the humid and high temperature of the external environment, the sebaceous glands will produce more natural oils, and bathing will not bring too much negative impact on the skin.
However, in winter, factors such as dry and cold weather and indoor heating can significantly reduce air humidity, accelerate the loss of skin moisture, and cause rough, dry, itchy, chapped and burning skin in some people, and even damage the epidermal barrier.
In this case, if you take too much bathing, it may interfere with the normal hydration of the skin and cause damage to the microecological balance, which will aggravate skin desquamation and itching, and increase the chance of skin infections and allergic reactions.
Hot water + soap = dry "doubled"
In comparison, hot water is easier to take away the natural oils on the skin surface than warm water, aggravating dry skin, leading to scaling, itching, and skin breakage.
Therefore, it is recommended that everyone use warm water for bathing and cleansing.
The appropriate water temperature should be roughly equal to or slightly lower/higher than normal body temperature, and the water temperature range of 32°C-40°C is more appropriate.
If you feel that your skin is enduring irritation or redness during the bath, it means that the water temperature is too high and you need to adjust it.
When washing your face or bathing, it is not recommended to use soap or soap to clean your skin.
In winter, especially the elderly, people with sensitive skin and people suffering from eczema and dermatitis, the use of soap and toilet soap should be minimized.
As an anionic surfactant, soap has a relatively higher pH (9-10) and is alkaline, so it may affect the weakly acidic environment of normal skin and is more likely to induce skin irritation; soap can remove natural oils on the skin surface , Reduce skin hydration, more likely to cause dry skin; excessive use of antibacterial soap products may also destroy the normal flora of the skin and promote the growth of more drug-resistant microorganisms.
Fragrance and additives in some soap products may also induce irritation or allergic reactions.
Therefore, we recommend the use of soap-free cleansers with a neutral pH value, such as soap-free facial cleansers, body washes, and body oils.
In the northern regions, if you use "hot water + soap" for a long-term bath, it is likely to aggravate dry skin and induce dermatitis and eczema.
Rubbing the "mud" is very refreshing but the skin is uncomfortable
Many people have the habit of taking a bath, because they feel that they can be cleaned in this way.
So, what is the "mud" that is rubbed off in the bath?
Do I really need to scrub hard when I take a bath?
The “mud” that is rubbed during the bath is not all “dirty things”. Its main component is the stratum corneum of epidermal keratinocytes. It also incorporates the metabolites, oil, sweat and dust adhering to the outer layer of the skin. .
As a dermatologist, we do not recommend vigorous scrubbing for two reasons.
On the one hand, scrubbing vigorously will destroy the skin barrier, allowing irritating substances, bacteria/viruses, allergens, etc. to enter the epidermis through the tiny damaged surface, causing skin trauma, inflammation, and infection.
On the other hand, if part of the skin area has infectious damage such as flat warts, common warts, and molluscum contagiosum, scrubbing may cause a "homonymous reaction" (referring to normal skin undergoing non-specific injuries, such as trauma, scratches, surgical incisions, etc.) , Sun exposure, etc., can induce the same skin changes as an existing skin disease), so that the above-mentioned skin lesions can be spread more widely.
In addition, in public bathrooms, if the bath towels are not properly disinfected, it may also cause the spread of infectious skin diseases.
It is advisable to take a bath two or three times a week
Regarding the frequency of bathing, dermatologists cannot give a uniform standard due to differences in individual skin types. However, it is still recommended that the public appropriately reduce the frequency of bathing in winter. For example, it can be washed every other day or 2-3 times a week according to personal circumstances.
However, for people who are troubled by odor, exercise a lot or have skin infections, bathing 2-3 times a week may affect personal hygiene and interfere with normal social activities.
For those with a higher bathing frequency, you may wish to refer to the following suggestions for healthy bathing.
●Do not scrub excessively. People with dry skin and the elderly are not recommended to overuse a bath towel or bath brush. If necessary, use it at most once a month;
●Control the bathing time within 5-10 minutes;
●Close the bathroom door to increase the environmental humidity;
●Do not overheat the bath water, the best temperature is between 32℃-40℃;
●Use mild detergents such as shower gel and shower oil instead of soap and toilet soap, but beware of the risk of falling when the elderly use shower oil;
●The movement of drying the skin should be as gentle as possible;
●Apply a lot of oily moisturizing cream or ointment immediately after bathing to lock the skin moisture (dry skin is recommended to use ointment, cream or face cream instead of lotion);
●If you only need to clean a part, try not to take a bath as a whole.
In addition, it is important to talk about middle-aged and elderly people, who are the main people with dry and itchy skin in winter.
With age, the production of natural oils in human skin will gradually decrease. Photoaging and skin aging will also make the skin thinner, making it difficult to keep the skin moisturized like young people.
In clinical practice, most elderly people suffer from dry skin and itching, especially in areas with less sebaceous glands on the body, such as arms, hands, upper back and front of lower legs, which can even cause chronic eczema and dry dermatitis.
For the elderly, there is no need to take a bath every day, 1-2 times a week in winter is enough.
If you need further cleaning, wipe the part with a warm towel as the case may be.
The specific bathing method is basically the same as the above recommendations for people with higher bathing frequency. In summary, it is to be short, use less alkaline cleaning agents, use warm water, avoid vigorous scrubbing, and apply moisturizer after washing.
In addition, for patients with skin diseases such as eczema, dermatitis, and topical glucocorticoids, remember to use them after bathing and before applying moisturizers.
Because the skin that has just been washed is in a highly hydrated state, it helps to absorb the drug.
Wash in the morning or at night
Speaking of the habit of bathing, some people are accustomed to bathing in the morning and feel refreshed; some people are accustomed to bathing at night to relieve the fatigue of the day.
Is there a difference between "Early wash" and "Late wash"?
Which habit is better?
In fact, bathing in the morning or bathing at night has no difference in cleansing and hydrating the skin, but there are indeed some clinical phenomena that remind us that bathing at night will bring greater benefits.
First of all, similar to the principle of the biological clock, the skin also has its own circadian rhythm.
Studies have shown that facial sebaceous gland secretion can reach its peak in the afternoon. Residual substances accumulated in work, entertainment, and makeup will accumulate on the skin at night. Therefore, taking a bath at night can better ensure skin cleanliness and bed hygiene, and help prevent, Reduce the occurrence of acne.
Secondly, warm bathing before going to bed can increase the blood perfusion of the palms and soles of the palms and expand the skin temperature gradient between the distal and proximal ends, thereby reducing the core body temperature and simulating natural thermal regulation during sleep to maintain better sleep quality.
Of course, this is not to say that taking a bath in the morning is definitely not good. For people who have the habit of waking up in the morning to study and exercise, taking a bath in the morning may be more beneficial to keep their minds clear and keep their hygiene after exercise.
Physician reminded
Sun protection is necessary in winter
Many people pay great attention to sun protection in summer and when the sun is strong, and will ignore this in autumn and winter.
In fact, whether it is cloudy or cold, ultraviolet rays will still shine on our skin, causing photoaging and skin damage.
In snowy days, ice and snow can even reflect up to 80% of ultraviolet rays, increasing the risk of exposure.
Among them, UVA with a shorter wavelength can penetrate the deep layer of the dermis and mediate photoaging.
Therefore, it is necessary to protect against UV damage through physical and chemical sunscreen in winter. It is recommended to choose sunscreen products that can provide broad-spectrum UV protection and have an SPF of at least 30.
How to choose skin care products
Before choosing moisturizing products, understand the normal structure and hydration of the skin.
The normal epidermis is divided into several layers. The outermost layer is the stratum corneum, which is composed of flat, non-nucleated keratinocytes and various lipids between the cells.
Ideally, the stratum corneum contains 20%-30% water, and the skin will appear smooth, soft, and plump. If the water content of the stratum corneum is reduced, the skin will appear dry and desquamated.
Based on the above situation, an ideal moisturizing product should contain the following 4 types of ingredients: 1. Water, water is usually the first in various skin care ingredients, if you simply apply oily substances without replenishing water at the same time, the hydration of the stratum corneum will still not be Improved; 2. Moisturizers that help absorb water, including ceramide, glycerin, sorbitol, hyaluronic acid, etc.; 3. Oily substances that help retain water to cover the surface of the skin and prevent moisture from evaporating, Including petroleum jelly, lanolin, mineral oil, organic silicon such as polydimethylsiloxane, etc.; 4. Emollients, used to fill the cracks caused by dryness, smooth and soften the skin, such as mineral oil, palm oil, linoleic acid , Lauric acid, etc.
We recommend using mild, fragrance-free skin care products in the cold and dry winter, choosing ointments, creams or face creams.
Of course, for people with oily skin or who are prone to acne or acne, you can also choose lotion or gel moisturizer according to your skin type.
(Author: Li Yingyi, Chief Physician and Chief Physician of the Department of Dermatology, Beijing Tsinghua Chang Gung Memorial Hospital, Zhao Yi)