Glycolic acid is a substance that chemically exfoliates a person’s skin by dissolving dead skin cells and oils. Glycolic acid may also help boost collagen production, and support skin moisture.

Glycolic acid can remove the very top layer of skin cells without the need for scrubbing, which can cause irritation. It is also useful in treatments for acne, hyperpigmentation, and the visible signs of aging.

However, as with all chemical exfoliants, using glycolic acid too frequently, at too high a concentration, or incorrectly can result in skin irritation or damage.

In this article, we discuss glycolic acid in detail, including its properties, benefits for the skin, and potential side effects. We also suggest how to choose a glycolic acid product and when to contact a doctor.

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Glycolic acid is a compound that naturally occurs in certain fruits, beets, and sugarcane. In its pure form, it is odorless and colorless.

Cosmetic and pharmaceutical companies include glycolic acid in topical products to treat skin conditions or to improve skin texture and appearance.

The acid that cosmetic companies use tends to come from a laboratory rather than natural sources.

Glycolic acid belongs to a group of acids experts refer to as alpha hydroxy acids (AHAs). AHAs are popular ingredients in skin care products.

Other types of AHA include:

Of these, glycolic acid has the smallest molecular structure, which likely allows it to penetrate deeper into the skin.

Glycolic acid has the following properties:

  • Exfoliative: As a chemical exfoliant, glycolic acid removes the outermost layer of skin cells and oil by dissolving them. Unlike mechanical exfoliants, such as face scrubs and brushes, glycolic acid does not require harsh scrubbing.
  • Humectant: Glycolic acid is also a humectant, which means it attracts and binds water to skin cells. It does this by increasing the synthesis of glycosaminoglycans, which are molecules that draw water in the skin.
  • Antibacterial: A 2020 study states that, at certain concentrations, glycolic acid can inhibit the growth of bacteria.
  • Anti-aging: Glycolic acid can reduce some of the processes that cause visible signs of skin aging. For example, it can reduce sun damage and increase collagen and hyaluronic acid in the skin. These substances give skin elasticity and structure.

Research suggests that glycolic acid may help with the following:


Older research from 1999 examined the effect of a peel containing 70% glycolic acid on 80 females with acne. The research found that it quickly improved all types of acne, particularly comedonal acne, which occurs when pores become clogged with oil and dead skin cells.

It is of note, however, that this strength of glycolic acid is only available as a chemical peel. Over-the-counter (OTC) glycolic acid products are not this strong.

UV damage

Exposure to UV light can cause skin damage. The visible signs of this include:

Health experts refer to this as photoaging.

A 2020 study notes that glycolic acid is an effective treatment for sun damage in the skin. A 2018 paper also reports that glycolic acid has a protective effect against UVB rays, meaning it may help prevent photoaging.

Lines and wrinkles

Over time, the skin loses its plumpness and elasticity. As a result, fine lines and wrinkles can form. This is a natural process and not necessarily something a person needs to treat. However, for those who choose to, glycolic acid may help.

According to a 2020 study, glycolic acid:

  • increases skin levels of hyaluronic acid, a substance that helps keep the skin moisturized
  • stimulates the production of collagen, the main structural protein in the skin
  • increases fibroblast and keratinocyte proliferation rates, which help with skin repair and regeneration
  • improves quality of elastin, which promotes skin elasticity


Warts are small, hard growths on the skin that occur due to viruses.

An older 2011 study tested the effectiveness of a 15% glycolic acid treatment in 31 HIV-positive children with warts. The results indicate that the treatment helped flatten and normalize the color of the warts, but it only completely cleared them in 10% of the participants.

Other research from 2011 evaluated the effectiveness of a gel containing 15% glycolic acid and 2% salicylic acid in 20 people with warts. The research found that the gel worked very well.

However, both these studies were small, and therefore, more research is necessary to confirm these findings.

All chemical exfoliants have some risks. They include the following:

UV damage

AHAs may reduce the signs of sun damage. However, because AHAs also remove the top layer of skin cells, they leave the cells underneath more vulnerable to further sun damage.

For this reason, it is essential to wear sunscreen every day before going outside and for 1 week after stopping glycolic acid use. A person will also need to avoid tanning beds.


Some people may have reactions to products containing glycolic acid. They may experience:

Symptoms such as burning are not a sign that the product is working. If any of the above occur, wash the product off and discontinue use.

These symptoms may also occur if:

  • a person uses glycolic acid that is too strong
  • they use it too frequently
  • they use it near the eyes

If glycolic acid gets in the eyes, rinse them under clean running water immediately.


Glycolic acid can be an effective ingredient for reducing hyperpigmentation.

However, strong or irritating skin care products can also cause hyperpigmentation. It is especially important for people who are prone to hyperpigmentation to use nonirritating, gentle exfoliants.

How a person chooses a glycolic acid product will depend on the results they want to achieve.

People can find glycolic acid in a wide range of formats, including:

  • cleansers
  • toners or face mists
  • liquid exfoliants
  • serums
  • moisturizers
  • acne treatments
  • face masks or at-home peels

Generally, however, products that have a leave-on formula will have the best results, as the formula gives the acid more time to work.

Individuals who have not tried glycolic acid before should look for products that have a low concentration of glycolic acid, of around 8%. This will allow them to start with a weaker solution and work upward, if they wish to.

It is also beneficial to look for a pH that is not too acidic. Most OTC products have a pH of around 4, which is not much more acidic than the skin’s natural pH. If the concentration or pH is not listed on the product, the company may be able to provide the information.

Before trying glycolic acid, it is important to seek guidance from a healthcare professional, such as a dermatologist, particularly if a person has an ongoing skin condition.

Glycolic acid is not suitable for everyone. A healthcare professional will be able to advise on whether the product is right for a person.

It is also important to wait until any broken or sun-burned skin has healed before applying glycolic acid to the area.

When a person is ready to try glycolic acid, they should do the following:

  • Do a patch test: Try the product on a small area of skin that is not on the face. That way, it is possible to see whether the skin will tolerate it. If no symptoms occur, apply it to the face.
  • Start slowly: It is best to start with a low strength of glycolic acid, using it infrequently at first. If the skin feels smoother and shows no signs of an adverse reaction, a person can slowly increase their use following the instructions on the product label. Do not use it more often than the label or a doctor advises.
  • Choose one product: There is no need to use an entire line of skin care that contains glycolic acid. One product is enough to get the benefits. Introducing one new product at a time also allows a person to see whether it is working.
  • Use at night: Glycolic acid increases the risk of sunburn, which is why some prefer to use it at night.
  • Apply sunscreen: Always apply sunscreen as the last step in the routine before going outside while using AHAs. The FDA advises wearing a sunscreen daily during the treatment and for at least 1 week afterward.

Glycolic acid is a chemical exfoliant that occurs naturally in some plants. Many skin care products and treatments contain it, although cosmetic companies usually use glycolic acid that comes from a laboratory.

This ingredient has exfoliating, hydrating, and anti-aging properties. It increases the amount of substances that help with skin regeneration and the production of collagen. However, it is important to use it correctly to avoid adverse effects.

If a person wishes to try a product containing glycolic acid, they should consult a doctor first. It is best to start slowly and use sunscreen when going outdoors, both during the treatment and for some time after.