PHAs for your skin? The facts behind the beauty hype

Countless Beauty Brands spend billions every year to make products that “smooth out” wrinkles – with sometimes impressive but always limited results.

Polyhydroxy acids (PHAs) are one of the latest hyped beauty ingredients touted to banish fine lines.

Older studies suggest that PHAs can help hydrate the skin and stimulate skin cell regeneration, which helps reduce the appearance of fine lines and wrinkles. Compared to similar exfoliating ingredients, they are less irritating, especially if you have sensitive skin.

Here’s what you need to know about PHAs, including how they work, how to use them, and where to find them.

Aging has multiple effects on your skin: The epidermis (the outermost layer of skin) thickens. The skin retains less moisture and contains less collagen. Sun exposure further damages cellular DNA. Together, these factors increase the appearance of wrinkles.

PHAs are a chemical exfoliant.

“Exfoliation helps slough off dead, dull skin cells, reveal healthy cells, reduce hyperpigmentation and improve skin texture,” says Dr. Dendy Engelman, practicing dermatologist at Shafer Clinic At New York.

PHAs also hydrate the skin. They support the skin’s barrier function, which retains moisture and reduces the appearance of fine lines and wrinkles.

The ingredient also has other benefits.

“PHAs potentially facilitate penetration of other active ingredients applied to treated skin,” says Dr. Tsippora Shainhouse, FAAD, board-certified dermatologist in private practice at SkinSafe Dermatology and Skin Care in Beverly Hills, California.

And PHAs have antioxidant properties that “help repair and prevent damage caused by UV-induced free radicals and pollution to collagen and skin cells,” she says.

The result? PHAs have an anti-aging effect, says Shainhouse.

According to Dr. Peterson Pierre, dermatologist at Pierre Skin Care Institute in Westlake Village, CA, PHAs commonly used in skincare products include:

  • gluconolactone
  • lactobionic acid
  • galactose

Are PHAs better for sensitive skin than BHAs or AHAs?

PHAs are a type of hydroxy (or fruit) sour. Other hydroxy acids include alpha hydroxy acids (AHAs) and beta hydroxy acids (BHAs).

All three are added to skincare products to help reverse sun damage, reduce the appearance of wrinkles, and make skin more elastic, toned, and hydrated.

However, PHAs may be less likely to irritate sensitive skin.

AHAs, including glycolic acid and lactic acid, are frequently added to skincare products to treat acne, scars, dark spots, dryness, and wrinkles. (Glycolic acid has the smallest particle size of all the hydroxy acids, so it’s the best exfoliator, adds Engelman.)

BHAs, like salicylic acid, are anti-inflammatory. They’re often recommended for oily or acne-prone skin, Engelman and Shainhouse say.

That said, these ingredients are not for everyone.

AHAs are known to cause swelling and burning and can make your skin more sensitive to the sun.

Although BHAs may be slightly less irritating than AHAs, the Food and Drug Administration (FDA) warns that they make the skin even more sensitive to the sun.

“While AHAs and BHAs are fantastic and have many benefits for the skin, they can certainly be harsh and cause irritation,” says Pierre.

Some research suggests that PHAs are almost as effective as other hydroxy acids and less likely to irritate your skin. This means you’ll likely tolerate them better if your skin is very sensitive or if you suffer from conditions such as rosacea or eczema.

“I like PHAs because they acclimate skin to exfoliation with little risk of irritation,” says Engelman.

For example, a 2004 study (paid for by a cosmetics company) compared PHAs containing gluconolactone to AHAs containing glycolic acid over 12 weeks. Researchers found that both ingredients had anti-aging benefits, but PHAs were less irritating.

“PHAs have a larger molecular structure than AHAs and BHAs, which means they take longer to penetrate and don’t penetrate as deeply,” says Engelman.

Shainhouse adds that PHAs may be associated with less sensitivity to the sun after treatment and a risk of sunburn and sun damage.

Another one 2004 study found that gluconolactone PHA prevented some UV damage in mouse skin cells.

The same researchers also tested PHAs on people. They found that the ingredient did not increase the risk of sunburn, suggesting it might be a better option than AHA or BHA for people with sensitive skin.

However, PHAs are not for everyone. If you find your skin is sensitive to the ingredient, Pierre says avoid it.

“Otherwise, they’re great for all skin types, even if you’re pregnant or breastfeeding,” he says.

PHAs are found in cleansers, toners, pads, masks, and even moisturizers.

Engelman prefers PHA buffers.

“It gives you the correct dosage in a clean, sterile delivery system,” he says.

Pierre maintains that serum or creams give maximum results.

“PLHIV need time in contact with the skin for you to see their beneficial effects,” he explains.

Whichever product you choose, follow these tips.

Check the label

Look for one of the following PHAs:

  • gluconolactone
  • lactobionic acid
  • galactose

Consider combining with AHAs or BHAs

If your skin tolerates it, choose a product that combines PHAs with AHAs, BHAs, or both. “They can do a better job and get better results,” says Pierre.

“Some of my favorite chemical exfoliants contain a mix of AHAs, BHAs, and PHAs,” says Engelman.

If you have very sensitive skin, PHAs alone may be your best bet. “They are great for all skin types, especially those with sensitive skin… [and] are gentle enough to use even if you suffer from rosacea or eczema,” explains Pierre.

Don’t overdo it

Although many serums use a combination of AHA, BHA, and PHA, “these are safe because they’re specifically formulated to be used together,” says Engelman.

Don’t buy separate chemical exfoliants and use them together. This can overwork and thin the skin, breaking the bonds of healthy cells, adds Engelman.

Partner with a Barrier Builder

To strengthen the skin barrier, Engelman and Shainhouse suggest looking for a PHA product that contains:

  • ceramides
  • hyaluronic acid
  • glycerine
  • peptides

Or pair your PHA exfoliator with another skincare product containing these ingredients.

“PHAs have moisturizing properties, which could be amplified by combining them with other anti-humidity ingredients,” says Shainhouse.

Test it first

Before slathering a new PHA product all over your face, test it on your forearm first. If it doesn’t irritate your skin after 24 hours, gradually incorporate it into your regimen.

Use as needed, but watch out for irritation

Pierre suggests using a new PHA product three non-consecutive days a week. Gradually increase the frequency as long as your skin tolerates it.

Ultimately, take your skin’s reaction as a signal. You may be able to use a cleanser, moisturizer, toner, or tampon every day. Or you might find it’s best to use toners and pads weekly, Shainhouse says.

Always follow label instructions. Most masks, for example, are meant to be used once a week or once a month, Shainhouse says.

Apply after washing and before moisturizing

Engelman says you can use a PHA product in the morning or evening after washing the skin.

“As with most exfoliating treatments, PHA masks and peels are best applied to clean skin,” says Shainhouse.

Always follow with a serum (if using one) and moisturizer to seal in moisture and protect the skin barrier.

Remember to finish with a broad-spectrum sunscreen during the day to avoid sunburn, adds Shainhouse.

Be careful with certain ingredients

Because PHAs are an acid, they should not be combined with pH-sensitive ingredients.

“That includes vitamin C, which is a very unstable molecule,” says Shainhouse. Instead, apply the vitamin C serum in the morning and your PHA exfoliator in the evening.

And as long as it doesn’t bother your skin, some to research suggests that retinyl acetate (vitamin A) may enhance the effects of PHA. Don’t apply products containing these ingredients at the same time to avoid irritating your skin, Shainhouse says.

For extra-sensitive skin, you can also try alternating between PHAs and retinoids daily, suggests Engelman.

Engelman recommends the following PHA products:

  • Elizabeth Arden Prevage Progressive Renewal Treatment.This 4-week at-home peel “provides excellent gentle exfoliation with AHAs and PHAs, leaving skin soft,” says Engelman. He suggests using it once every few months.
  • Glo Skin Beauty Pro 5 Liquid Exfoliator. “This peel combines AHAs and PHAs for effective yet gentle exfoliation. Skin will look brighter after just one use,” says Engelman. The combination of mandelic acid, lactic acid, gluconic acid, malic acid and tartaric acid is safe for all skin types, he adds.

Other recommended skincare products with PHA include:

PHA products can be a bit pricey, but more economical options include:

PHAs, including gluconolactone, lactobionic acid, and galactose, are chemical exfoliants that moisturize the skin and help reduce the signs of aging.

They are less irritating and less likely to cause sun sensitivity than other chemical exfoliants. This makes it a better choice if your skin is sensitive or prone to rosacea or eczema.

If this doesn’t bother your skin, choose a product that combines PHAs with BHAs or AHAs for the best results. Apply to clean skin and follow with moisturizer.

Patricia J. Callender