Best Exfoliating Acids for Aging Skin

The best exfoliating acids for aging skin are glycolic acid and lactic acid, two alpha hydroxy acids (AHAs) tested in randomized trials on sun-damaged skin. In a 22-week trial of women aged 40 to 70, 8% creams of each improved overall sun damage on the face more often than a plain cream did. Glycolic suits skin that handles a tingle. Lactic suits drier or more reactive skin. If your skin stings with both, a gentler polyhydroxy acid (PHA) such as gluconolactone is the one to try.

Which exfoliating acid works best on aging skin?

Glycolic and lactic acid have the strongest human evidence for aging skin. In a double-blind trial of 74 women with sun-damaged faces, women applied cream twice a day for 22 weeks. Overall sun damage improved by at least one grade in 76% of women using 8% glycolic cream, 71% using 8% lactic cream and 40% using a plain cream.

The results are real but modest. The researchers called both creams "modestly useful" for some signs of sun damage. They also noted that women tolerated both creams well and that both are sold without a prescription. The trial compared each acid with the plain cream, not glycolic with lactic. It doesn't crown a winner between the two.

Acids work by making the top layer of skin shed faster. According to the FDA, how much they exfoliate depends on the type of acid, its strength, its pH and the rest of the formula. Two 8% glycolic products can behave differently on your face.

The same trial also tested the creams on women's forearms. By week 22, lactic acid improved blotchy dark spots and rough texture there, and both acids improved dullness. That is a good sign if spots and rough texture on your arms bother you. It still isn't proof of what lactic acid does on the face.

Glycolic, lactic or PHA: which one fits my skin?

Pick the acid your skin will put up with day after day. A gentler acid you keep using does more for you than a strong one you quit after a week of burning.

What strength of glycolic or lactic acid should I buy?

For home use, look for 10% or less with a pH of 3.5 or higher. The cosmetic industry's safety panel considers glycolic and lactic acid products safe for consumers in that range. Its conditions are that the product protects against sun sensitivity or tells you to use daily sun protection.

A higher percentage won't automatically give you better results. A review of AHA research found that high concentrations break down the bonds holding the skin's surface together and cause irritation, while low concentrations may help the skin.

Stronger acids belong in an office. In a small study, a dermatologist applied 70% glycolic or 85% lactic peels for three minutes, once a month for three months, to women aged 35 to 60. Each group had nine women. Both peels reduced fine lines at the outer corners of the eyes. Right after a peel, the women had redness and some burning. The researchers saw no adverse events.

Salon peels go up to 30%. The safety panel considers them safe only for brief, occasional use, rinsed off thoroughly, applied by trained professionals and paired with daily sun protection.

Do exfoliating acids make your skin more sensitive to the sun?

Yes. In FDA research, people used an AHA cream for four weeks. Afterward their skin reddened 18% more easily under UV light, and UV damage to skin cells doubled on average. The effect varied a lot from person to person.

The effect starts fast and goes away. Glycolic acid as weak as 4%, used for as little as four days, changed how skin responded to UV. One week after people stopped using it, the extra sensitivity was gone.

The FDA's sunburn alert for AHA products says to "use a sunscreen, wear protective clothing, and limit sun exposure while using this product and for a week afterwards." Sun exposure speeds up the same aging you're using the acid to treat. Skipping sunscreen works against your effort.

If your skin tone is deeper, you should know that most AHA studies were done in lighter skin types. Studies in deeper skin are still needed. In one study, skin pretreated with glycolic acid also tanned more under UVB light than untreated skin. Ask your clinical team what to watch for.

What can exfoliating acids not fix?

Acids work on the surface. The FDA describes AHA products as aimed at fine lines, surface wrinkles, texture and tone, and they work by shedding surface skin. They won't lift sagging jowls or fill deeper folds that come from lost volume.

One Reddit commenter said the same thing. On a post from a 37-year-old about lower-face sagging despite years of skincare, the top comment said "no amount of creams and “drink more water” suggestions will stop volume loss."

If an acid has smoothed your texture and you want more for your lines, the next step is a prescription. Tretinoin is a prescription retinoid, and our clinical team can prescribe it if it fits your goal. Ask your clinical team before adding it to an acid routine.

If an acid has done what it can and you want more for your lines, take the quiz. Our clinical team will look at your skin goals and see whether tretinoin fits your plan.