What Is PHA In Skincare? Experts Reveal All

When it comes to chemical exfoliants, most people are familiar with acids like AHAs and BHAs. However, thanks to research in product development and more reasonable market prices, the skincare industry is starting to utilize another effective yet gentler alternative to what has long been considered the gold standard of chemical exfoliants. Enter: PHAs. This lesser-known acid wields a ton of benefits, which is why you may want to consider adding it to your skincare routine. But what is PHA, exactly? Ahead, we tap an expert to give us the lowdown on this buzzy ingredient.

What Is PHA?

PHA is an acronym for polyhydroxy acid. It is a second generation of alphahydroxy acids, or AHAs as they're more commonly known. If you're curious as to whether or not PHA acids are in some of the products you're already using, gluconolactone, galactose, and lactobionic acids are the most common PHAs found on ingredient lists.

What Are the Benefits of PHAs?

As a chemical exfoliant, PHAs will promote cellular turnover. "This may improve clogged pores and breakouts, as well as the appearance of fine lines," says Ava Shamban, MD, Beverly Hills dermatologist and founder of SKIN FIVE. These acids can also minimize pigmentation caused by photo-aging, sun damage, or exposure to UV rays that have directly affected the melanocytes [skin cells that form melanin].

Similar to AHAs, Dr. Shamban says that PHAs also attract and bind water molecules to the skin which can help keep skin hydrated. "These acids are humectant, so they have the ability to support moisture retention in the extracellular matrix, giving a firmer, plumper appearance to the skin," says Dr. Shamban. "They also render excess iron in the skin 'inactive,' purging an element that is often in overdrive as we age and can speed up the cellular aging process."

Which Skin Types Should Use PHAs?

PHA acids are a great addition to a skincare routine focused on anti-aging, or sensitive skin types that react to other chemical exfoliants. "Even those with more sensitive skin or who are highly reactive can easily tolerate PHA more readily," says Dr. Shamban. "PHA products are also known to be safe for people with rosacea or some skin conditions like eczema, which is not possible with AHA and the BHA acid groups."

How Do PHAs Differ from AHAs, BHAs, And Other Acids?

PHAs are larger in molecular size than AHAs and BHAs, which means that they're only able to exfoliate the outer layers of the skin. "AHAs are the middle of the road," explains Dr. Shamban. "BHAs really dive deeper into the skin, dissolving sebum and dead skin cells down in the pores, so they are often more suitable for oily skin and keeping acne at bay."

Another reason to switch PHAs: Sun sensitivity isn't an issue. Many products with AHAs and BHAs in them recommend applying them at night or limiting your sun exposure if used in the morning. Dr. Shamban says that PHAs are completely safe to use in your daily skincare routine, but don't skip on wearing sunscreen and a hat if your plans for the day include being outside.

How Do You Use PHAs?

From masks to serums to moisturizers, you can incorporate PHA acids into virtually any step of your skincare routine. Dr. Shamban says that the ingredient is safe to use every day, but suggests introducing a new PHA acid product into your routine three times a week and building the frequency up from there. Don't expect to see miracles overnight, but stick with it to see the best results.

As for products, there's a handful of options out there that can suit a variety of different skincare routines. Glossier's Solution is an Instagram-popular exfoliating toner that includes AHA, BHA, and PHA acids to clear pores and reduce breakouts. Meanwhile, Glow Recipe's Avocado Melt Sleeping Mask combines the firming, moisturizing power of PHAs with everyone's favorite fruit. Zelens PHA+ Bio-Peel Resurfacing Facial Pads are a quick-and-easy way to exfoliate, and PCA's Hydrating Serum boosts moisture levels and plumpness, to name a few.