How does baking soda help with facial acne?

Acne is a common problem that can occur not only in adolescence, but at any age. It can be triggered by a lack of sufficient hygiene, the use of decorative cosmetics, a lack of vitamins, poor diet and hormonal imbalances.

Acne causes not only psychological, but also physical discomfort, since the affected areas of the skin are subject to acute inflammation.

To treat lesions in severe forms, potent pharmacological drugs are used, but in some cases you can limit yourself to safer means, including regular soda.

How can baking soda help get rid of acne?

The effectiveness of baking soda in treating facial acne is much lower than that of specialized skin care products or pharmacological drugs, but in the initial stages it can help solve the problem.

It is possible to achieve a positive result thanks to the following methods of influence:

Neutralization of acid-base imbalance in the upper layers of the epidermis, which is one of the common causes of acne on the face;
Antiseptic effect and suppression of inflammatory processes, which leads to the elimination of existing acne or a reduction in their number;
Drying the skin and removing excess fat produced by the sebaceous glands, which prevents clogging of pores and the subsequent development of inflammation;
Exfoliation of the upper layers of the skin and removal of dead cells, which becomes possible due to the special structure of the product obtained by mixing soda and water;
Evens out facial tone and eliminates excessive pigmentation.

How to treat acne correctly?

Inflammation is the primary link in the pathogenesis of acne18. It has been shown to precede follicular hyperkeratosis18. Treatment of acne that affects the pathogenesis links is considered effective, and the more of them the therapy affects, the better.

Unfortunately, there are currently no drugs that could have the same effect on the entire cascade of reactions that provoke rashes. Therefore, dermatologists practice combination treatment. For example, one combination prescribed for mild to moderate acne may be a topical antibiotic and azelaic acid or benzoyl peroxide28,18. This reduces the risk of developing antibiotic resistance28.

Clindovit® gel is a topical antibiotic; the main active ingredient in its composition is clindamycin phosphate6. The drug must be used twice a day6.

*acne

Precautionary measures

Baking soda is a relatively safe remedy for treating facial acne as long as you take precautions.

Which are as follows:

If your skin is hypersensitive, you should use topical soda with extreme caution , as it can cause redness, burning and other discomfort;
Regardless of skin sensitivity, it is recommended to pre-test soda to make sure there is no negative reaction from the body;
In the absence of an undesirable reaction, you still cannot use soda on a regular basis , since this can give the opposite result: a violation of the acid-base balance, leading to the growth of pathogenic microflora, the development of inflammation and an increase in the number of acne on the face;
The recommended frequency of topical application of baking soda on the face is 2 times a week.

What to do?

First of all, assess the condition of your skin. Too thin, dehydrated skin with peeling or scratches and wounds, this substance can burn and injure. It’s better to protect yourself and first apply the mask to your wrist, watch yourself: if after thirty minutes everything is fine, move on to your face.

Do not use the powder in its pure form. And remember the time: you can’t fall asleep with these masks on, they should be left on for a maximum of 10 minutes.

You should not abuse them and use them as a means for every day: you can use them no more than once a week or every two weeks. Doing it more often will only cause harm.

How to do an allergy test?

Even if you are not prone to an allergic reaction, it is recommended to first test the soda for an allergic reaction.

This is done quite easily according to the following scheme:

A small amount of baking soda is mixed with water to make a thick paste;
The resulting mixture is applied to a small area of skin on the back of the hand;
After 30-40 minutes, it is necessary to check the reaction : the absence of itching, burning, swelling, redness and other signs of allergy in the treated area is evidence of its absence.

After successfully passing the allergy test, you can safely apply baking soda to your face to get rid of acne.

Washing with baking soda

Washing with baking soda is the most effective facial treatment method for those with oily skin.

This technique can be practiced at the beginning of winter or spring for preventive purposes to create additional reliable protection of the facial skin from the effects of negative factors.

The procedure is carried out in accordance with the following instructions:

A teaspoon of baking soda is added to a glass filled with warm water , the liquid must be stirred until the product is completely dissolved;
You need to wash your face with the resulting soda water ; you should not wipe it after this, since the skin of your face must absorb the volume of liquid it needs;
10-15 minutes after the procedure, you need to wash your face with plain water to wash off the remaining soda from your face.

An alternative way to wash your face is to wipe your face with a cotton swab dipped in water with the addition of soda.

Particular attention should be paid to the area under the eyes - in these areas the tampon can be kept for 3-7 minutes, which will additionally help get rid of puffiness.

The frequency of washing depends on the current condition of the skin:

When undergoing a procedure for preventive purposes or for deep cleaning, washing with soda should occur no more than once a week so as not to disturb the acid-base balance;
If you have a large number of pimples on your face, washing with baking soda can be done up to 4 times a week, every other day. It is recommended to coordinate such treatment with a specialist.

Using baking soda in a targeted manner

One option for using baking soda against acne is using it as a spot treatment, which is a quick way to combat acne.

Detailed instructions for preparation and subsequent processing are given below:

Baking soda and warm water are mixed in equal proportions , usually a few tablespoons of each is enough to obtain a paste with a suitable thick structure;
Before undergoing the procedure, the face must be washed and cleansed in any usual way; you can use special products in the form of gel or milk;
The resulting product is applied pointwise with your finger to individual pimples . If there are open lesions, a short-term tingling may occur, which is a normal reaction and does not require immediate removal of the paste;
15 minutes after application, the soda paste is washed off the face with plain water;
You can apply the product to acne spots and leave it on your face all night and wash it off in the morning. The effectiveness of treatment in this case increases, but along with it the risk of excessive drying and peeling of the skin also increases;
After spot use of soda, it is recommended to additionally moisturize your face ; for this you can use a cream with the appropriate effect.

Useful tips and tricks

A soda mask for acne is an effective remedy, but to achieve maximum effect, follow a few rules:

Before procedures, use a cleansing gel or foam for washing.
When applying homemade mixtures, avoid the area around the lips and eyes - these are too sensitive areas.
Before exfoliating with soda for acne, make sure that you are not allergic to the components. To do this, apply it to the inner bend of your arm and wait an hour.
The products are not suitable for use on areas with open, purulent wounds, burns and other significant damage to the epithelium.
Apply the mixture only with gentle movements, otherwise you will damage the protective layer of the epidermis.

Not a single scrub, even the best one, will get rid of acne if you don’t follow a healthy lifestyle and eat right.

“Home cosmetologist” is an accessible and time-tested therapy, which, however, requires careful handling and strict adherence to instructions.

If allergies or hypersensitivity are detected, it is better to turn to other methods of combating acne.

Recipes for effective masks based on baking soda

A variety of face masks with the addition of baking soda allows them to be used to treat acne by those with any skin type.

General rules for applying soda masks to the face are given below:

Application of masks is allowed only on skin that has undergone preliminary cleansing;
The skin must be moisturized before applying the mask ; just sprinkle water on it;
The mask is applied with light finger movements ; unlike a scrub, it should not be rubbed in;
The duration of the procedure is 5-10 minutes ; in any case, it is not allowed to keep the mask on your face for more than 15-20 minutes, as this can cause side effects and aggravate the situation;
Frequency of applying masks to treat acne: once a week.

Baking soda mask with lemon juice

A mask that, in addition to baking soda, contains lemon juice and moisturizer, is well suited for treating acne for those with dry skin.

Method of preparation and use:

Soda is mixed with nourishing cream in equal quantities, usually 1 teaspoon of each component is enough;
A few drops of freshly squeezed lemon juice are added to the product;
After thorough mixing, the mask is applied to the face; the thickness of the layers can be increased in places with acne accumulation or severe inflammation;
After 10 minutes, rinse with warm water.

Soda-based mask with sour cream added

For dry skin, you can also use a sour cream mask, which effectively eliminates all skin rashes and has a moisturizing effect.

Method of preparation and use:

A teaspoon of sour cream of any fat content is mixed with half a teaspoon of soda.
The facial skin is not only cleansed beforehand, but also steamed.
Apply in thin layers, avoiding the area around the eyes;
The mask should be kept on the face for about 20 minutes, after which it can be washed off.

Egg soda mask

A soda mask with the addition of egg white is good for treating acne that occurs on oily skin.

Method of preparation and use:

The egg white is mixed with a teaspoon of baking soda, after which both components must be beaten with a mixer;
The product is applied to the face in even thin layers; rubbing into the skin should be avoided;
After 10 minutes, the mask can be washed off with warm water.

Universal mask based on soda

Below is a recipe for a mask that can be used not only for the face, but also for application to problem areas of various parts of the body.

This product is approved for use regardless of skin type, but it cannot be used more than once every 1.5-2 weeks.

Method of preparation and use:

A tablespoon of soda is mixed with the same amount of table salt;
The dry mixture is diluted with a tablespoon of a solution based on laundry soap;
Application is carried out in thin layers, after 10-15 minutes the mask can be washed off.

After using any soda-based mask, it is recommended to wipe the skin with a piece of ice and chamomile infusion.

Cleaning your face with baking soda

It has an abrasive, polishing effect, so it will be a good alternative to a store-bought facial scrub or peeling. Basic cleaning rules:

keep the mask for no more than 10 minutes;
Use boiled or purified water, mineral water, but without gases, is also suitable;
It is advisable to repeat the procedure every 10 days or a little less;
Before using a new recipe, do an individual tolerance test in a separate area;
Be sure to apply cream after cleansing.

Use only a freshly prepared mask, since baking soda may react with other components during storage.

Baking soda scrubs

Using baking soda, you can prepare scrubs that will become effective helpers in the fight against acne.

The following describes the process of preparing and using a product that can effectively cleanse oily skin:

Mix a tablespoon of table salt with a teaspoon of soda;
Dilute the dry mixture with a few tablespoons of warm water to obtain a paste that needs to be mixed thoroughly;
Rub the mixture into the skin of the face with light movements, rinse with warm water 5 minutes after completion of treatment;
The duration of the course is 10 days; with longer use of the scrub, the skin may become too dry.

Sometimes a small amount of coffee grounds is added to a scrub for oily skin - it provides the skin with a large number of useful microelements and nutrients. When using this component, you need to keep the scrub on your face for 10 minutes, otherwise the procedure is carried out according to the same scheme.

To treat acne when the skin tends to dry out, it is recommended to use the following scrub recipe:

Mix a teaspoon of cream, half a teaspoon of baking soda and a tablespoon of natural bee honey;
The components are thoroughly mixed to ensure uniformity of the structure, after which the mass is applied to the face;
The product is rubbed into the skin, the epidermis receives a set of necessary vitamins and nutrients contained in honey, but it must be taken into account that it can also cause an allergic reaction;
After 10 minutes, the scrub can be washed off the face with warm water.

Application for blackheads

Soda powder softens the epithelium and expands the pores during use, therefore effectively removing blackheads from the surface layer.

Scrub

This scrub removes about 80% of open comedones localized on the nose in one use. To prepare it, you should:

Grind rice or buckwheat flakes into flour;
Mix 15 g of soda and the resulting flour;
Add 7 cinnamon powder;
Add mineral water without gas to the dry mixture until a thick consistency is obtained;
Massage the mixture into the skin for several minutes;
Wash.

Mask

For old comedones that are difficult to remove, baking soda helps with blackheads. Step by step recipe:

In a convenient bowl, mix baking soda and filtered water until a thick, creamy mass is obtained;
Wash thoroughly and apply to the area prone to comedones;
Wash off with soap after 10 minutes;
Treat yourself with tonic.

Tonic

A significant advantage of this tonic is that it can be stored in the cold for a long time and there is no need to prepare a fresh portion each time. The drug not only gets rid of blackheads, but also brightens the face. To prepare you need:

Mix freshly squeezed lemon and purified water in equal proportions;
Add soda at a ratio of 15 g per ½ cup of the resulting solution;
Wipe your face with a cotton pad soaked in the composition 2 times a day.

Peeling based on baking soda

Soda peeling is considered one of the most effective cleansing procedures at home. With its help, you can get rid of existing skin problems and reduce the likelihood of recurrence of acne on the face.

During its passage, the effect is only on the upper layers of the dermis, so the procedure is painless and does not injure the skin.

Peeling with honey and soda

This peeling involves the joint use of baking soda and honey and helps get rid of blackheads.

Instructions for carrying it out are given below:

Both components are mixed in equal proportions; any type of honey will do; a prerequisite is that it is natural;
The soda-honey mixture is applied gently with massage movements;
After 10 minutes, rinse off without soap or gel;
It is recommended to do it weekly, repeat for a month, then take a break.

Soda here cleanses the dermis, honey restores and nourishes it. But it is worth remembering that honey is highly allergenic.

Peeling with cosmetics

Peeling can be done using facial wash or cosmetic gel; this option will help relieve inflammation, narrow pores and prevent drying out.

The instructions are given below:

The selected cosmetic product is poured into a separate container or palm, it must be foamed;
Add 10 grams of sea salt and 10 grams of baking soda, the mixture is thoroughly mixed;
The mixture is rubbed into the facial skin for 1-2 minutes, paying special attention to problem areas with acne accumulation;
After the procedure, you need to wash your face and treat your face with a cream with a moisturizing effect.

Peeling with hydrogen peroxide

This peeling can normalize the functioning of the sebaceous glands, eliminate their secretions and slightly dry out problem areas.

Peeling is carried out in accordance with the following instructions:

Soda in a volume of 10 grams is mixed with such an amount of 3% hydrogen peroxide to obtain a thick paste-like mixture;
To increase effectiveness, a few drops of tea tree essential oil are added to the composition;
The peeling mixture is rubbed into the face for a minute, after which it must be washed off;
After the procedure, it is recommended to additionally moisturize your facial skin.

Brutal peeling

Brutal peeling is practiced for deep and high-quality cleansing of pores, which helps prevent the recurrence of acne for a long period.

The procedure is carried out according to the following scheme:

Salt, soda and shaving cream are mixed in equal quantities, the components are mixed until a mass with a uniform structure is obtained;
The resulting product must be rubbed into the skin of the face with circular massaging movements, paying special attention to problem areas;
After 10 minutes, the mass is washed off the face with warm water; no need to use soap;
After the procedure, it is recommended to wipe your face with fresh lemon.

Steam facial cleansing at home

Before steam facial cleansing at home, wash the skin with gel or cosmetic milk, then apply a scrub, massage for several minutes, and then rinse off. The water should be warm, the scrub can be made at home or bought ready-made

It is important that the grains of the product are small and gentle

For effective steaming, hold your face over boiled water for 10 – 15 minutes. The bowed head should be covered with a terry towel. The effect of this method of facial cleansing at home is increased by medicinal herbs (mint, chamomile) added to boiling water.

The steamed skin is wiped with hydrogen peroxide, hands with some alcohol tincture. You should apply pressure with your fingertips, not your nails, so as not to injure the skin. To prevent infections, your index fingers can be wrapped in a bandage. You should not squeeze out unripe blackheads: it is better to leave them for next time.

During the procedure, the face is wiped with peroxide several times. After completing the manipulations, the pores must be narrowed using a tonic with alcohol, and then moisturize the skin with cream. Facial cleansing at home using the steam method is done once every two months.

Using Baking Soda for a Bath

Soda baths are not only a way to get rid of acne, but also a good procedure for general healing effects on the body.

Its use allows you to achieve the following positive results:

Elimination of acne not only on the face, but also on the back, shoulders, neck and other parts of the body;
Complex antiseptic effect, elimination or reduction of local inflammation;
Cleansing the lymphatic system and stimulating natural metabolism;
Stimulation of blood circulation processes and destruction of fungal microflora;
Providing a calming effect during nervous overstrain.

Baths with the addition of soda are recommended for people with oily skin to normalize the functioning of the sebaceous glands, as well as for those with rough skin, since the procedure will help soften it.

To obtain a positive result, you must take such baths in accordance with the following instructions:

The maximum water temperature during the procedure is +38°C;
To take a bath you will need 150 grams of baking soda, it is recommended to add 300 grams of sea salt to it;
All components are pre-mixed in a separate container and diluted with warm water; the resulting solution is then poured into the bath;
The duration of stay in water should not exceed 15 minutes;
After completing the procedure, it is recommended to wrap yourself in a warm robe or blanket and go to bed.

Baking Soda Recipes for Acne Spots

Homemade recipes with baking soda are effective not only in combating rashes, but also in combating their consequences. Let's look at the most effective recipes.

Anti-stain mask with baking soda and oatmeal

This method will require natural ingredients that are involved not only in skin whitening, but also have an additional positive effect on post-acne.

The process of its preparation and use is described below:

20 g of oatmeal are pre-ground in a coffee grinder , a teaspoon of soda and a little hot water are added to it;
The mixed composition, after swelling, is applied to cleansed skin with acne marks;
Leave for 10 minutes , and excess mask is removed with damp cotton pads.

This mask also perfectly relieves inflammation on problem skin.

Recipe with added baking soda and sugar

Sugar-soda product is intended for deep cleansing of facial skin. The presence of additional components in it allows you to saturate the deepest layers of the epidermis.

The process of its preparation and use is described below:

Dissolve a teaspoon of granulated sugar and the same amount of baking soda in a glass of warm water, mix all ingredients thoroughly;
The resulting mixture is applied to a cotton pad , which is then used to wipe the surface of the face containing acne marks;
Apply with light massaging movements for 3-4 minutes;
Wait until the product remaining on your face dries completely , then wash your face; it is recommended to use mild soap to enhance the main effect;
Let your face dry naturally , then wipe it with butter;
Wait 1 hour and wash again with warm water , this time you should stop using soap.

Adding baking soda to cosmetics

Baking soda can be used to add to various cosmetic products to increase their effectiveness in treating facial acne.

Suitable for these purposes:

Various lotions for facial skin care;
Tonics for the treatment of acne;
Ointments and other products for topical use with low density.

With such treatment, there is a combined effect, feeding the epidermis with care products and cleansing the skin with soda, and the soft structure reduces the risk of damage from soda particles.

You can prepare a product based on this component using the following instructions:

The selected cosmetic product in a volume that is usually taken for a single application is placed in a separate container;
A small pinch of baking soda is added to the cosmetic product , after which the mixture is thoroughly mixed;
Apply the product with the addition of soda to the skin of the face with light finger movements , while you need to make smooth massaging movements for deeper cleansing of the pores;
Additional moisturizing after treatment is not required ; such treatment can be carried out 1-3 times a week.

Reviews

Elena, 36 years old: “My daughter is now at the age when pimples and acne do not give her rest - a transitional age. She uses various expensive cosmetics, but they do not help. And then I remembered the product that I, my mother, and my grandmother used. And it turned out that this remedy is still relevant today. My daughter started using baking soda to wash her face, and her acne began to go away.”
Ekaterina, 30 years old: “Acne is my problem, and I have suffered from it almost all my life. I read a lot of reviews on the Internet about using baking soda for such cases. And I decided to try. After a month I saw the result, now I will use this product until the problem goes away completely.”
Nadezhda, 28 years old: “I use baking soda as a facial scrub. It cleanses the skin of acne and exfoliates. I do the scrub 3 times a week, but you can do it 2 times. After a month, my face became very clean, the effect was amazing. Before I started using this scrub, blackheads especially appeared in the forehead area, as well as all over my face. I tried a lot of gels and scrubs, their prices also varied greatly. But in the end it turned out that soda is both effective and worth a penny. Pimples stopped appearing. But it is worth noting that it is ideal for oily skin, but not so much for dry skin. You can simply dry out your face. Therefore, you need to know moderation in everything.”
Angelina, 45 years old: “Soda – how much is hidden in this word. The product is used both as a cosmetic and as a universal detergent. One day, after a hot summer, I noticed that my skin began to look simply terrible. I was so swamped with work that I had no time for self-care. The skin became oily, the pores became clogged, pimples and blackheads appeared. And this is where baking soda came to my rescue. Every day I applied a mask of baking soda and water to my face. After some time, the skin became clear, without acne, and the complexion improved.”
Natalya, 25 years old: “When acne appeared on my face, I, like all girls, began to buy a variety of products to overcome them. And then I was simply horrified to discover that I was allergic to the components contained in the care products. Now I was faced with the task of how to fight. I decided to try soda, because it definitely couldn’t get any worse. I started using a mask that also included hydrogen peroxide. The result I received exceeded all my expectations."

Can you drink baking soda as an internal remedy for skin problems?

In folk medicine, baking soda is used internally to solve many health problems. Such procedures are aimed at normalizing the acid-base balance and a general healing effect on the body, due to which the number of skin rashes also decreases.

Taking soda orally is carried out according to the following scheme:

Dissolve a teaspoon of baking soda in a glass of warm boiled water and stir the solution;
The product should be taken orally in small sips; it is recommended to do this in the morning before breakfast;
Reception is carried out on a daily basis, 1 time per day.

Contraindications for use

Despite the positive effect it has on the body, bicarbonate is a drug of chemical origin, and its abuse will lead to unpleasant consequences: nausea, irritation of the epidermis, burns of the mucous membranes. For this reason, treat the method with caution and under no circumstances exceed the dose (maximum 1 tbsp per day).
The substance is contraindicated for those suffering from dermatitis and psoriasis; patients with chronic ulcers, gastritis and diabetes, kidney, liver and gall bladder diseases.
The medicine should not be diluted with milk or dissolved in cold water.
After ingestion, it is not recommended to eat for half an hour.
“Home cosmetologist” is applied to problem areas only during the absence of pustules.

Important Application Tips

When using baking soda topically to get rid of acne on the face, consider the following recommendations:

Soda has contraindications even for external use , and their absence should be ensured before starting treatment;
Despite the safety of the product, you should not use it too often : once a week for preventive purposes, 3-4 times a week when treating acne;
When using baking soda more than 1-2 times a week, it is better to consult a doctor about such treatment;
Regardless of the frequency of use of soda, it is necessary to monitor the condition of the skin ; at the first signs of peeling or drying, use a moisturizing cosmetic product;
It is not recommended to use soda to treat acne on the face in the hot season , or to combine such procedures with visiting a solarium or beaches. Excessive thermal exposure increases the risk of drying out and microtrauma.

Compound

Baking soda is a powder with small grains. It is a sodium salt of hydrocarbonate acid. Of the useful minerals, it contains sodium and selenium.

The crystals are characterized as soft alkali. They are odorless, dissolve well, and taste slightly salty. Calorie content is zero due to the absence of proteins, carbohydrates and fats.

What contraindications does it have?

Topical use of soda to treat acne has a number of contraindications, including the following:

Open wounds and damage to the integrity of the skin in the treated area;
Inflammatory processes in the acute phase on the treated area;
Local varicose veins and the presence of burst vessels in the treatment areas;
Allergic reaction that occurs to the use of soda;
Dry skin type or tendency to dry out . In this case, soda is prohibited only in its pure form, but it can be added as an auxiliary component to a cream or gel with a moisturizing effect.

Causes of acne

Acne can appear for obvious reasons or come as a surprise.

Scientists distinguish several types of acne: comedones, papules, pustules, nodular cystic and fulminant acne. An individual approach is applied to the treatment of each type.

Main prerequisites for the development of the disease:

Adolescence (puberty) age. During this period, accelerated development of the body occurs - this greatly affects the functioning of hormones that do not have time to adjust to the desired pace. As a result, the sebaceous glands secrete too much sebum.
Hormonal disruption can also occur in adulthood: for example, in women, pregnancy and the menstrual cycle greatly affect the activity of hormones. In men, the disease is observed against the background of endocrine changes in the body.
Poor environment, dust and dirt can also cause acne. In this case, much attention is paid to daily cleansing of the cover.
Reaction to certain medications, such as weight gain steroids.
Working with acnegenic products (cosmetics, chemicals), leading to the formation of acne.
The susceptibility to the disease is influenced by genetics: everyone has different skin thickness, inherited from their parents.
Gastrointestinal diseases, metabolic disorders.

You can only fight ordinary, shallow comedones on your own.

Attention! Nodular-cystic and especially fulminant acne signal severe stages of the disease and require immediate attention to a specialist.

In other cases, it is possible to treat the disease at home using folk methods and cosmetics.

It is important to remember that traditional medicine is not a panacea, and organics are more effective as part of complex therapy.

Side effects

External use of baking soda to treat acne rarely causes side effects.

However, if the basic rules for using the product are not followed, it can lead to the following undesirable reactions:

Redness at the application sites , accompanied by itching and burning;
Drying of the skin , leading to peeling;
Increased activity of the sebaceous glands due to the removal of too much natural fat;
Violation of the acid-base balance due to the systematic use of soda;
The worsening of the situation and the appearance of even more rashes most often occurs when exposed pimples are treated with soda.

Benefits for skin

Sodium bicarbonate is widely used not only in the food industry, but also in medicine and cosmetology. With its help, you can cope with gastrointestinal pathologies, neutralize burns, and improve the functioning of the genitourinary system.

Main healing properties for acne:

Normalization of the pH balance of the upper layer of the dermis;
Regulation of the sebaceous glands;
Drying;
Calm;
Anti-inflammatory effect;
Restoring normal color;
Suppression of the activity of pathogenic bacteria;
Narrowing of pores.