Guide to Using Alpha Hydroxy Acids (AHAs)

If you enjoy using skincare products, you’ve probably come across several that include hydroxy acids of some kind. Well, hydroxy acids may sound like a really potent acid when you hear or read about them, but they have a number of advantages that can help to improve your skin. Depending on the requirements of each type of skin, hydroxy acids are available in a variety of forms. Alpha hydroxy acids, or AHAs, such as glycolic acid, can smooth out uneven skin textures, tighten sagging skin, and even out the skin tone.

AHAs are strong, though, and if you use them without taking good care of your skin, you risk doing more harm than good. If you’re interested in learning how to use AHAs, keep reading because we’ll explain how it can help with a variety of skin issues, including scars, acne, hydration, pigmentation, sun damage, and aging. We’ll go over its various varieties, advantages, and recommended uses.

What are Alpha Hydroxy Acids (AHAs)?

AHA in a bottle, serum, skincare product, beauty product

Alpha hydroxy acid, or AHA, is one of the two hydroxy acids most often used in cosmetic products for hydration and exfoliation. This component is frequently present in skincare treatments intended to combat aging. They can be produced synthetically or organically from foods including fruits, nuts, sugar, and dairy products.

Other typical hydroxy acids exist as well, such as beta hydroxy acid, or BHA. Alpha hydroxy acids cannot penetrate the skin like BHAs do since they are water-soluble, in contrast to BHAs, which are soluble. AHA is therefore excellent for skin that is thicker, older, or sun-damaged but does not have acne problems. When it comes to the surface of the skin, AHA is quite effective. By severing the connections between the skin cells on the outer layer, it can exfoliate the top layers of skin. It can remove dead skin, exposing fresh, healthy skin underneath.

Additionally, AHA is hydrophilic, or it draws water molecules to it. In order to make the skin feel bouncy and moisturized, it can aid in helping it retain more water. Your skin may, however, become more sun-sensitive as a result. This means that you must constantly wear sunscreen if you wish to use AHAs in your skincare routine. If you don’t, you’ll be exfoliating to achieve fresh, healthy skin only to have the new skin become even more damaged when exposed to the sun.

AHAs come in concentrations ranging from 1% to 50% or even greater, making them more potent exfoliants. So that you won’t run the risk of over-exfoliation, you will need to increase your skin’s tolerance from a lower to a higher concentration. Remember that excessive exfoliation is challenging to restore and may take months.

AHA can aid in accelerating the process of removing dead skin cells from the top layers of the skin. Even while it doesn’t happen instantly, using AHA will speed up the process and reveal fresh, bright-looking skin. Because of this, AHA is frequently included in products that aim to lessen hyperpigmentation, sun damage, and acne scars.

Types of AHAs

molecule models

AHA is available in a variety of forms, as was previously mentioned.

    • Glycolic Acid: Sugarcane is the source of glycolic acid, which is great for exfoliating dead skin cells, balancing skin tone and texture, and stimulating the production of collagen. Since it is the smallest molecule in the group, it can penetrate the skin more easily. Additionally, it directly affects the activation and growth of fibroblasts, which are the cells that generate collagen and lessen wrinkles and fine lines.
    • Lactic Acid: Lactic acid generated from milk is gentler on the skin than glycolic acid and is frequently recommended for skin types with more sensitivity because of its larger molecule size, which makes it more difficult to penetrate deep within the skin. Because the acid in sour milk has a smoothing effect on the skin, Cleopatra is claimed to have taken baths with it. Additionally, it thickens and strengthens the skin, aids in minimizing wrinkles and fine lines, and lessens acne by reducing bacteria.
    • Citric Acid: As its name suggests, this citrus-fruit derived AHA gives the skin a decent amount of antioxidants and promotes skin cell turnover. Citric acid exfoliates and has astringent qualities, therefore it works well on oily skin.
    • Malic Acid: A mild AHA that works well for mild exfoliation, brightening the skin, and keeping the pores free of blocking debris, pollution, oil, and dead skin is malic acid, which is derived from apples and other fruits. Malic acid pairs well with other AHAs for a stronger punch because of its mild nature. It can also act as a humectant to keep the skin moisturized.
    • Mandelic Acid: Almonds are the source of mandelic acid. Since its molecules are even larger than those of lactic acid, it does not penetrate the skin as quickly and offers benefits that last for a longer time. This one is excellent for those with sensitive skin that is prone to rashes and irritation. This AHA can also be used if you want a skincare regimen that has some AHA power without expecting immediate results.
    • Tartaric Acid: Although tartaric acid is more popular in the beauty industry, it has long been present in foods like grapes and tamarinds. It works well to provide moisture because it is a mild exfoliant that also aids in binding water to the skin. It also regulates the pH of your product and keeps the stability of your beauty products.

Benefits of AHAs

beautiful healthy facial skin, fresh healthy skin

By definition, all acids will exfoliate the skin, but AHAs go above and beyond that requirement. Here are a few benefits of using AHA.

  • It is a surface exfoliant: When skin cells die, they frequently cluster together and adhere to the skin’s surface. AHAs facilitate them to gently peel away by dissolving the “glue” that binds them together. The outcome? Basically everything you desire, such as more radiance, a smoother texture, and fewer dark spots. For people with sensitive skin, for whom physical exfoliation (also known as manual scrubbing) may cause redness and inflammation, this chemical exfoliation is what makes AHAs a desirable option.
  • It can help treat acne: Because AHAS can speed up exfoliation and break the bonds that bind skin cells together, it also has the ability to open or loosen congested pores on the skin’s surface. Studies have shown that AHA works well to treat mild to moderate acne. In addition, it can aid in preventing subsequent outbreaks following a more powerful acne treatment.
  • It can help treat hyperpigmentation: According to studies, AHAs can also aid in reducing sun damage spots, scars, post-inflammatory hyperpigmentation, and other skin discolorations. This is also due to the fact that it speeds up exfoliation of the skin’s surface.
  • It can increase collagen production: AHAs can affect the skin’s deeper layers (or the dermis) in addition to its surface layer. According to studies, all AHAs boost collagen production to some level, but none more so than glycolic acid, the AHA that is most frequently used in anti-aging treatments. Less lines and wrinkles also result from increased collagen.
  • It helps in hydrating the skin: The humectant properties of glycolic, malic, and lactic acids cause them to draw moisture to the skin. Additionally, lactic acid is a particularly good choice for people with dry skin.
  • It offers antioxidant benefits: Citric acid stands out among the AHAs for its antioxidant capabilities, which makes it a perfect choice for fighting free radical damage and lightening dark spots.

Who Can Use AHAs

AHAs with larger molecules, such lactic acid, are often better tolerated and should always be used on very sensitive skin types. Higher concentrations of just just about any type of AHA, notably glycolic and citric acids, work very well on oily, acne-prone skin.

However, it is advised to wait at least a week or longer after any in-office procedure until the skin has fully recovered before starting to use AHAs again. The majority of people can tolerate them, however avoid using them on skin that is highly sensitive or hypersensitive.

How To Use AHAs

patch test on skin

First, decide which AHA you want to use. The smallest of these acids, glycolic, produces the most notable effects. Make sure to use a modest quantity if you have sensitive skin; higher concentrations are best reserved for people with normal to oily skin. For those with sensitive skin, lactic acid, which has a larger molecular size, is an excellent choice. Malic acid, which has an even larger molecular size, may be less irritating. Still, a good rule of thumb is to pick a product that uses moderate levels of a variety of AHAs rather than a high concentration of a single type. Because different acids penetrate at different depths and have distinct hydrating properties, mixing them at lesser concentrations may be less irritating even if a high concentration of any one acid can produce noticeable benefits.

Second, the kind of product also matters. AHAs are included in a wide range of products, from creams to cleansers, however it is advised that those with sensitive skin start with wash-off formulations to reduce their exposure to the active ingredients. It goes without saying that you must stick to the product’s instructions. Never exceed the recommended frequency of usage; instead, begin slowly and increase it gradually as tolerated.

Third, although a little acidic, conditions with a pH between 5 and 6 are where AHAs perform best. AHA becomes less effective if you apply additional products on top of it too soon because it can alter the pH environment of your skin.

Lastly, a patch test is essential if you have never used aAHAs before or if you are unsure of how much your skin can tolerate. Apply an AHA on the inside of your elbow with a drop, just as you would with your face. Then observe to see if it exhibits a negative reaction. If so, the AHA product that you currently have is not suitable for you and could have a damaging effect on your face.

How to Incorporate AHAs into Your Skincare Routine

The acid you choose will determine how frequently you should use any AHA. After that, consider your skin type, the climate where you reside, and the precise directions for the product.

AHA-based skincare products are generally safe to use as part of a daily skincare routine. Nevertheless, depending on the product, some are better suited for application once or twice a week, or until the skin adjusts and can tolerate them daily. Additionally, it’s always best to introduce new products, like an AHA, into your regimen gradually.

Once the skin has gotten used to the routine and there is no sensitivity, you can add an exfoliating lotion once a week, increasing the frequency as the skin tolerates it.

Important Things to Know About AHAs

If you intend to use AHA cleansers, keep in mind some of the following things:

  • The skin does not need to peel with a peel: Earlier variants of acid-based exfoliation procedures could actually cause the skin to visibly shed. The most recent formulas today can leave skin radiant and flake-free. Today, many products contain multiple alpha and beta hydroxy acids rather than simply one at a higher concentration. Additionally, acids become less irritating when combined at lower concentrations. Furthermore, you do not need to expect or see peeling effects in order to observe the benefits. Thousands of skin cells are separating as the acid breaks the cement holding the skin cells together, but they are not visible to the naked eye.
  • The acid percentage is not everything: An acid product’s potency depends entirely on the free-acid compounds floating inside of it. If there are too many acid bits, you will experience burning and reddening of the skin. On the other hand, too few acid particles have no effect. Chemists are experimenting with the pH in this way to change the quantity of free acids. The optimal pH range is between 3 and 4, but this information is typically not provided on product packaging. As a result, keep in mind that an AHA product should cause your skin to tingle for a short while after use. You will experience something if it is working. There will also be some immediate gratification. Your skin should look renewed as soon as possible if the product is effective.
  • People who have sensitive skin can also use AHA cleansers: You should be aware that acids do not stimulate inflammation the way retinoids do to heal skin. Acids disintegrate the top layer of cells to start the repair process. Additionally, unlike scrubs, AHA cleansers do not use abrasives that harm the skin. Therefore, acids are a fantastic option if you have sensitive skin. Look for cleansers with formulations that have an amino acid to limit the penetration of these ingredients into the skin.
  • One acid is better than the rest: Keep in mind that a molecule will penetrate the skin more easily the smaller it is. Glycolic acid has the most dramatic results because it has the smallest molecules of all the acids. Glycolic acid is one of the most often used acids in anti-aging products because of this. Additionally, glycolic acid renews collagen, thickens the dermis and epidermis, and evens out skin tone.
  • Acids do not work for deep wrinkles: Keep in mind that cleansers and other over-the-counter acid products cannot remove deep wrinkles from the skin. Only fillers and laser procedures have that capability. Acids can reduce fine wrinkles and lighten blemishes, but they also have their limitations.
  • AHA can work wonders below the neck: You can extend your AHA cleanser and cream a few inches down if you’re trying to treat a blotchy chest. Additionally, you can get rid of bacne by using a salicylic body wash. Applying lotions with AHAs will clear pores and dissolve dry skin if the back of your arms are feeling rough.


AHAs are helpful in improving the appearance of the skin. However, you must exercise prudence and use caution when using them. Make sure you follow accordingly all the recommendations for products containing AHAs if you plan to incorporate them into your skincare regimens.