スキンケアの乳酸の肌への効果と注意点

The effects of lactic acid in skin care products on the skin and precautions

Is lactic acid Cleopatra's beauty secret?

Lactic acid is used for exfoliation. It has a "peeling" effect, which anyone interested in beauty has probably heard of at least once. In fact, did you know that this "peeling" has a very long history?

Its origins lie in ancient Egyptian medicine.
A 1550 document states that peeling was a centuries-old practice.

Speaking of ancient Egypt, there is Cleopatra, who is said to be one of the three most beautiful women in the world. She also took baths in spoiled milk to maintain her youthfulness.
I was surprised to learn that spoiled milk contains lactic acid, which can help remove dead skin and reduce blemishes and wrinkles.

By the way, it seems that the ancient Greeks and Romans also used decayed limestone and other materials to pursue youth in a similar way.

Is lactic acid the secret to Cleopatra's beauty?

What is Lactic Acid?

The raw material for lactic acid is lactose, a carbohydrate contained in milk, which is then fermented to produce lactic acid.
Not only in ancient times when Cleopatra was alive, but even today it is used in many skin care products as a beauty ingredient with peeling effects.

Lactic acid is an alpha hydroxy acid (AHA) . There are several AHAs, including glycolic acid. Among them, lactic acid is said to have skin benefits that other AHAs do not have.

The effects of lactic acid on the skin

Exfoliating Care

Lactic acid is said to promote cell turnover, which means it helps remove dead skin cells that build up on the epidermis (the top layer of skin).

Wrinkles

Higher concentrations, such as 12%, are expected to result in overall smoother skin and less fine lines and wrinkles , as they penetrate deeper into the skin.

However, because it has such a high penetration power , it can also be very irritating to the skin. Therefore, people with sensitive or weak skin should use it at a low concentration of around 5%. However, you can still expect the same effect on the surface of the skin.

Stains

Lactic acid also works on skin pigmentation, making age spots and pores less noticeable.

Acne

For acne-prone skin, exfoliation with lactic acid can be too harsh. However, dermatologists often prescribe lactic acid in combination with antibiotics because it is effective. A study of 22 acne sufferers showed the following results:

  • Patients were asked to apply a 5% lactic acid lotion to their entire face twice a day.
  • After one year of treatment, most patients saw a 50% to 100% reduction in acne.

This means that my acne symptoms have disappeared or have healed by about half.
The study also noted that acne tends to worsen during hot and rainy weather, and that the results were consistent with the use of antibiotics in addition to lactic acid lotion.

Can it be used on sensitive skin?

What people with sensitive skin should be careful about when using lactic acid

Lactic acid is the mildest of the AHAs. It is said to be safe for use on sensitive skin at the appropriate concentration. However, if you have sensitive skin, it is best to pay attention to the following three points.

1. Make sure the concentration of lactic acid is 10% or less . The concentration is often not listed on the ingredient list. If you are unsure, it is best to ask the manufacturer.

2. Be careful about how often you use it . There is a risk of damaging the skin's barrier function by exfoliating too much. It is best to limit your use to at least once every two days.

3. Do not use with cosmetics containing retinol or scrubs
Using these products at the same time puts too much strain on the skin. In severe cases, inflammation may occur and cause pigmentation.
If you put too much stress on your skin, it will produce extra melanin, and the resulting pigmentation may take a long time to fade.

Be careful of UV rays when using lactic acid

After using lactic acid to exfoliate your skin, you are at higher risk of skin damage from UV rays. Whether you are outdoors or indoors, be sure to apply a sunscreen with SPF 30 or higher. If you are exposed to direct sunlight, don't forget that you need to take extra precautions against UV rays, such as reapplying sunscreen every two hours.

How to choose a sunscreen: Why you should choose a sunscreen that is free of UV absorbers

The risks of using lactic acid in skin care

When using cosmetics containing lactic acid or other AHAs, it may cause unexpected skin reactions. If you are trying lactic acid for the first time, here are some things to keep in mind:

  • Redness
  • swelling
  • Burning and tingling sensation
  • Tingling sensation
  • Severe itching
  • Peeling or turning of the skin

If you experience any of these reactions, consult a dermatologist as soon as possible and stop using any cosmetics that contain peeling ingredients, such as lactic acid, as these can further irritate and stress already damaged skin.

Once turnover is complete, discontinue use.

The effects of lactic acid are most noticeable when your skin's turnover is disrupted and you are unable to remove dead skin cells yourself, such as when you experience acne, stiffness, or roughness.

Once these conditions have improved and skin turnover has become normal, try stopping the use of AHAs such as lactic acid for a while. If your skin seems to be in good condition without lactic acid, you may want to refrain from using it to avoid unnecessary skin stress.

Also, as mentioned above, lactic acid can be used by people with sensitive skin. However, if your skin has excessive turnover, you should still use it with caution. In the following cases, the turnover cycle may be too fast, which may cause unnecessary skin problems.

  • The skin is already red
  • The skin is thin and easily irritated
  • Always have dry skin

"Excessive" skin care is never good for your skin. It is recommended to do skin care with the awareness of compensating for what is lacking.

Useful information is being distributed via LINE

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"CONCIO" - A company that thoroughly researches the risks of cosmetic ingredients

CONCIO is the first additive-free skin care product in Japan to receive EWG certification, meeting new standards.

Focusing on the risk of skin irritation and allergies caused by cosmetic ingredients, we strictly adhere to our own safety standards and do not use 2,500 ingredients.
We deliver world-class peace of mind to sensitive skin in Japan.

https://concio.jp/

CONCIO Minimalist Skincare

*This does not guarantee that skin irritation or allergies will not occur in all people.

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