Lactic acid is an alpha hydroxy acid (AHA) that exfoliates the skin, reduces fine lines and wrinkles, fades hyperpigmentation, and helps with acne.
Lactic acid is also a humectant, meaning it chemically attracts water molecules to itself and hydrates the skin. This hydration prevents new fine lines and wrinkles from developing and boosts collagen production for firmer, more youthful-looking skin.
1. It Exfoliates Dead Skin Cells
The lactic acid found in milk is a gentle alpha hydroxy acid (AHA) that exfoliates the skin and helps reduce dark spots, fine lines, and wrinkles. It is a popular ingredient in OTC chemical exfoliants and professional facial peels.
Lactic acid is keratolytic, which means it loosens the bonds between dead skin cells on the skin’s surface to reveal new, healthy skin underneath. It also improves the skin’s natural ability to retain hydration by stimulating lipid renewal.
It is a milder acid than glycolic acid and works well on most skin types, including sensitive skin. It’s an AHA that can be found in many over-the-counter products and in stronger concentrations in facial chemical peels at a dermatologist.
Because lactic acid has a larger molecule size than glycolic acid, it is more gentle on the skin and doesn’t have harsher side effects. It may cause light tingling and redness for the first few times you use it, but this is normal.
2. It Prevents Acne Breakouts
Lactic acid, an alpha hydroxy acid (AHA), is a water-soluble exfoliant that works on the skin’s surface. It’s keratolytic, which means it breaks down dead skin cells that clog pores & prevents acne breakouts.
It’s also an anti-inflammatory, reducing redness and swelling. It also helps keep pores clear & prevents blackheads from forming by unclogging them, and it’s a natural humectant, which makes it great for dry skin types.
It’s safe for topical use in concentrations of up to 10% in skin care products and can be used daily or 1x-3x a week as tolerated. But be warned, it can have mild side effects such as tingling or redness. If you experience irritation, consult a doctor or dermatologist.
3. It Reduces Pigmentation
Lactic acid exfoliates your skin’s surface and helps reduce the appearance of dark spots, age spots, sun damage, blotchy pigmentation, and acne scars. It also evens out the complexion and brightens your skin tone without whitening it.
AHAs or alpha hydroxy acids (lactic acid, glycolic acid, and citric acid) help fade excess pigmentation in your skin, including blotchy pigmented skin, surface scars, freckles, sunspots, and melasma. AHAs in concentrations of 5-12% work to fade hyperpigmentation by hastening the shedding and renewal of surface cells that have a buildup of excess pigment.
Low-concentration lactic acid products (OTC and professional-grade) should not cause any hyperpigmentation, but stronger chemical peels with higher than 10% concentrations can increase the risk of the inflammation that may lead to post-inflammatory hyperpigmentation, which is darker spots that appear as your skin reacts to treatment. This type of hyperpigmentation usually goes away within a few months.
4. It Reduces Fine Lines & Wrinkles
Lactic acid is the gentler AHA in the alpha hydroxy acid (AHA) family, which makes it a great option for people with sensitive skin. Other AHAs, like glycolic acid, can be harsh on the skin and cause irritation if used in high concentrations.
When using lactic acid on your skin, it may cause a tingling or burning sensation that goes away after a few minutes. This is a normal reaction and does not mean the product is not working.
It can reduce the appearance of fine lines & wrinkles by deeply exfoliating the skin’s surface. It also speeds up skin cell renewal, promotes faster collagen production, and strengthens the skin’s natural ability to retain hydration.
But be sure to follow up with a moisturizer with hyaluronic acid or another humectant as it helps speed the process of smoothing out fine lines and wrinkles. You can also consider combining it with retinol, but it is best to separate them into two applications – one in the morning and the other at night.
5. It Prevents Dry Skin
Lactic acid exfoliates by breaking the bonds that hold dead skin cells in place. Think of your skin cells as a wall of bricks that are held together by mortar. Without the bonds, the dead cells are free to break away from each other and fall off your skin.
This exfoliation helps your skin maintain its natural moisture by improving its barrier function. It also stimulates the production of healthy lipids and ceramides that help prevent moisture loss.
Lactic acid is a gentler AHA compared to glycolic acid and can be used by all skin types. However, if you have sensitive or dry skin, we recommend testing a lactic acid product before using it daily to avoid any adverse reactions.
6. It Boosts Collagen
Lactic acid helps boost collagen, which is the protein that gives skin its elasticity. Collagen levels decrease around age 25, and it can lead to sagging and loose skin.
It also encourages the growth of new skin. However, if your skin lacks pigment, you’re more prone to sunburn after using it.
To make the most of lactic acid, it’s important to use a low-strength product and follow up with sunscreen. It’s also best to discontinue strong exfoliating products, such as retinoids or scrubs, while you’re using them.
Overall, lactic acid is an excellent way to treat acne-prone skin. It exfoliates dead skin cells, kills acne-causing bacteria, increases cell turnover, and prevents breakouts. It can even help lighten and reduce hyperpigmentation.
7. It Prevents Sun Damage
Lactic acid is one of the gentler alpha hydroxy acids (AHAs) that help reduce fine lines and wrinkles, fade hyperpigmentation, and boost collagen production. It’s also a powerful exfoliant and humectant (moisturizing ingredient) so it’s a good choice for normal to dry skin.
However, as with all AHAs, lactic acid increases your skin’s sensitivity to the sun, so it’s important to use it in conjunction with sunscreen. Celebrity aesthetician Renee Rouleau recommends using a hydrating serum after lactic acid treatment to protect your newly exfoliated skin from the sun’s damaging UV rays.
Lactic acid helps dissolve the mortar between dead skin cell bricks, allowing them to release easily and smoothly. It also unclogs pores and acts as an astringent so it can be used to help shrink enlarged pores.
It also has strong antimicrobial properties against acne-causing bacteria – making it effective in preventing breakouts and reducing inflammation.
Lastly, it can help fade discoloration and post-breakout marks that involve excess pigment.
8. It Moisturizes the Skin
Lactic acid is a water-soluble alpha hydroxy acid (AHA) that works to exfoliate dead skin cells and boost cell turnover. It also has a humectant property that mimics your body’s natural ability to keep skin moisturized.
As a result, it can help you achieve clearer, smoother skin. Additionally, lactic acid has the added benefit of being an effective blemish-fighter and can reduce breakouts caused by bacteria.
It improves the skin’s barrier function by promoting the production of ceramides, which are healthy fatty molecules that help lock in moisture. It also stimulates the renewal of lipids, which are essential for maintaining hydration and reducing fine lines and wrinkles.
Lactic acid is safe for use in concentrations of 10% or less in at-home skin care products and professional treatments and chemical peels performed by a licensed esthetician or dermatologist, but higher concentrations can lead to skin irritation and increased sun sensitivity.
To avoid these side effects, perform a patch test and apply daily sunscreen when using products with lactic acid.
9. It Prevents Acne
Lactic acid prevents acne because it speeds up your skin cell turnover rate and helps the body naturally exfoliate dead skin cells. It also opens up pores that are clogged by dead skin cells, excess oil, and the precursors to all forms of acne.
Often, the first time you apply lactic acid to your face or other affected areas, your skin may feel tingly, which is normal and a sign that it’s doing its job.
However, if the skin is feeling inflamed or breaking out in places you didn’t expect, discontinue using the product immediately and check with your esthetician to see which products are best for your unique situation.
The body uses lactic acid for energy, fuel cells, and to produce glucose in other tissues (gluconeogenesis). It also acts as a molecular signal molecule throughout the body that attracts blood cells and immune cells. When blood cells aren’t getting enough oxygen or glucos
