According to dermatologists, there are major benefits.
While they may sound a little harsh, there’s a reason acid-infused skincare formulas are a mainstay on counters and vanities. That’s largely because few ingredients can resurface, exfoliate, clarify, and make skin glow quite like they can. While there are a variety of acids in skincare that serve different roles for different skin types, today we speak to you about PHA. No, we don’t mean AHAs and BHAs, but a new breed of acid with its own list of benefits. So what is PHA? We spoke to experts to learn more about one of the largest skincare acids in the game.
POLYHYDROXY ACID (PHA)
TYPE OF INGREDIENT: Exfoliant
MAIN BENEFITS: Repairs skin, exfoliates away dead skin, reduces the appearance of skin damage.
WHO SHOULD USE IT: PHAs are usually safe for all skin types, but especially for those with oily or acne-prone skin.
HOW OFTEN CAN YOU USE IT: To start, try using PHAs three times a week. You can use it in the form of a toner, a face wash, or even a serum.
WORKS WELL WITH: Other acids in low concentrations.
DON’T USE WITH: Other acids in very high concentrations, retinoids if you’re particularly sensitive.
What Is PHA?
PHAs, also known as polyhydroxy acids, are the newest acid to take over ingredient lists and newsfeeds all over the beauty world. “PHAs (Poly-hydroxy acids) fall under the AHA family. They are much larger in size compared to the more common AHAs like glycolic and lactic acids. Examples of PHAs are lactobionic acid and gluconolactone. Essentially, their benefits are the same as AHAs,” explains Ng.
Chang elaborates, “Because of their larger structure, PHAs do not penetrate as deeply into the skin but rather work on the outer layers of the skin. They tend to be less sensitizing and gentler as compared to other chemical exfoliants. PHAs are used on the skin for their exfoliating, skin smoothing, moisturizing, and anti-aging benefits, and may be a good alternative in patients with sensitive skin, including those with rosacea and eczema, who cannot tolerate AHAs and BHAs.”
Benefits of PHA
- Great for sensitive skin: According to Chang, PHAs are a lot gentler on the skin because they have a larger molecule size. That means they take a little longer to properly sink in, and they’ll never travel quite as deep as a straight-up AHA.
- Non-irritating: Sensitive skin types should be able to apply a PHA with little-to-no stinging or irritation.
- Maintain skin hydration: PHAs are humectants (meaning they retain moisture reserves) and contribute to the most glowing of complexions.1
- Anti-inflammatory: These acids may be best known for their exfoliation properties, but they come armed with tons of anti-inflammatory and antioxidant properties.
- Fight glycation: PHAs combat glycation, a process that weakens collagen and elastin in your skin.2
AHA vs. BHA vs. PHA
“PHAs (polyhydroxy acids like lactobionic acid) are similar to alpha-hydroxy acids but they are more superficial—acting and less irritating,” says MacGregor. “Think of these like a light and bright peeling agent that is more user-friendly. A dry, sensitive skin type with pigment and a little sun damage, for example, might use PHAs followed by moisturizer (or combined) to brighten, smooth, hydrate, and plump the skin—a quick refresh.”
First, you’ve got your AHAs (alpha-hydroxy acids), and that covers your glycolic, citric, and lactic acids. They all have their own strengths, but they mainly work by nibbling away at skin cells to reveal more glowy skin hiding underneath. AHAs can be pretty intense, so depending on the concentration of your product, you probably want to limit your usage to once or twice a week. As always, start off slow and see how you go.
Then you have your BHAs, or beta-hydroxy acids, which is where salicylic acid can be found. This type of acid is brilliant at flushing out blocked pores, which is why you always hear it recommended for things like acne or keratosis pilaris—that rough skin you have that never quite seems to go away.
And then comes PHAs or poly-hydroxy acids—the new-gen AHAs if you will. “PHAs are used to improve the tone and texture of your skin, but without extensive loss of surface skin cells and without commonly experienced irritation from AHAs,” says Nazarian. “PHAs can be found in facial pads, toners, and even leave-on lotions.”
Side Effects of PHA
The good news is that PHAs aren’t known for having side effects—that’s kind of the whole point. Instead of going deep into your skin, they gently wash away any debris that’s sitting on top of it. It’s why they’re so beloved, and such an easy ingredient to use. However, they are still acids, so if you have sensitive skin, do a patch test.
Skin Considerations
The best part? PHAs can be used with any skin type, from dry to oily, and sensitive skin types can even benefit from using this gentler acid. “PHAs are one of the best-tolerated chemical exfoliants and can be used by just about everyone, although I always recommend starting with infrequent use, monitoring for allergy, and avoiding areas of broken skin,” says Nazarian, adding that those with acne-prone skin should be cautious of any irritation.
How to Use It
PHAs are used in a ton of products and a few different ways. “They are best used in products that are left on the skin for an extended period to give them sufficient time to loosen the bonds between the outermost epidermis/skin cells. They can be incorporated into any product type—liquid exfoliant, toner, mask, or moisturizer,” says Ng.
A lot of AHA solutions will have PHAs in them to clean up the surface-level debris AHAs miss. Sometimes, PHAs are added as an extra exfoliating factor to a non-exfoliating product so the dead skin cells are washed away and the properties of the product—usually a serum—can be seen. And sometimes, PHAs are the main selling point.
But that’s not all: PHAs may also be the most versatile of the acids, which means they can be combined with plenty of other treatments. Chang explains: “PHA can be combined with other ingredients or dermatologic procedures to provide additional benefits to therapy. PHA can be combined with retinoids when treating acne or photoaging. PHA can be used in conjunction with hydroquinone to improve skin pigmentation and aging. PHA may also be used after cosmetic procedures, such as laser and microdermabrasion, but should be done in consultation with your dermatologist.”
FAQ
- Can I use PHA every day?Yes, for many people PHAs are safe to use every day. According to Nazarian, the benefit of using this type of chemical exfoliant is that it tends to have minimal penetration through the top layer of skin (due to its larger molecular size). “PHA can offer exfoliation without too much irritation, and also has the ability to stimulate enhanced hydration,” she says. Products with PHA can likely be used twice a day. It may be best to begin using it as part of your nightly routine.
- Can I use PHA and salicylic acid together?Yes, PHA can likely be used simultaneously with salicylic acid for a do-it-all skincare approach. “Although it can be used as a single therapy, it is often found combined with other types of acids such as alpha-hydroxy acids, and beta-hydroxy acids,” says Nazarian. “The level of penetration varies for each acid category, and there are additional benefits to the other acids that can be combined to target multiple skin concerns, such as oil production or acne.”