What Are PHAs? Why This May Be The Holy Grail Exfoliant For Sensitive Skin

August 3, 2020

Although commonly known chemical exfoliants, AHAs and BHA namely, are a go-to for many because they offer numerous benefits—from improving skin tone evenness to revealing a smoother complexion—most skincare enthusiasts have also experienced the occasional (or not-so-occasional) adverse reaction to the use/over-use of these skin-smoothing superstars. In fact, going overboard with an exfoliating acid may as well be a skincare rite-of-passage! The side effects of overusing an acid include increased skin sensitivity (including photosensitivity), redness, a burning sensation when applying other products (especially products with active ingredients like vitamin C), flaking, and/or a dry, tight feeling. Sound familiar?

These skin woes can all be connected to a compromised skin barrier. Essentially, your skin barrier (or acid mantle) helps skin maintain hydration while staying resilient in the face of environmental aggressors. Overuse of exfoliants, both physical and chemical, wear away at this vital layer, illustrating a fact that some of us have had to learn the hard way: there’s a fine line between perfecting skin with exfoliation and damaging skin with exfoliation. Sigh.

PHAs—A Smart Alternative to AHAs and BHA Exfoliating Acids

What Are PHAs? The Lesser-Known Exfoliant Cropping Up Everywhere

Fortunately, there’s an even gentler chemical exfoliant that simply hasn’t gotten the same level up hype that AHAs and BHA have—PHAs (polyhydroxy acids).  PHAs are actually the second generation of AHAs. Like their forebears, PHAs help slough off dead skin cells to help skin appear smoother but do so more gently without increasing sun sensitivity. “The skin actually becomes more tolerant so PHAs don’t increase the number of sunburned cells or make your skin more sensitive,” Dr. Elizabeth Briden explains.

Benefits of PHAs for Sensitive Skin

By sloughing debris off only the outermost layer of skin (rather than penetrating more deeply like AHAs and BHA), PHAs offer many of the same benefits as other exfoliants without threatening your acid mantle. Benefits include softer, smoother skin, more even skin tone, and reduced signs of cosmetic aging. PHAs also offer their own unique benefits not necessarily shared with AHAs and BHA.

Dermatologist Frances Prenna Jones explains, “They’re a special type of AHA that strengthens the skin’s barrier function and fight the signs of aging without the irritation of the classic AHA.” Wait, what? They strengthen skin’s barrier? Interestingly, polyhydroxy acids attract water molecules and help skin stay hydrated—and a hydrated complexion is skin barrier 101.

Furthermore, PHAs chelate iron from skin. (I know, I know…huh?) Apparently, iron is already present in skin, but too much may speed the aging process, according to Dr. Briden. PHAs render excess iron inactive or “purge” it, so it’s less likely to cause damage to skin.

Vegan & Cruelty-Free Products with PHAs

The Inkey List Polyhydroxy Acid (PHA) Gentle Exfoliating Toner

What Are PHAs? The Lesser-Known Exfoliant Cropping Up Everywhere

PHA (3%), niacinamide, and aloe vera make this a gentle, lightly hydrating toner. It targets dullness, uneven tone, fine lines, and dark spots. (This is temporarily sold out, but keep your eye on it—it’s super affordable.)

Exuviance Hydraprep pH Balancing Toner

What Are PHAs? The Lesser-Known Exfoliant Cropping Up Everywhere

PHA, aloe vera, hyaluronic acid, and algae extract help balance skin’s pH while gently exfoliating and attracting moisture to cells.

CosRX Low pH Barrier Mist

COSRX Low pH PHA Barrier Mist (75 ml.)

Formulated with gluconolactone and coconut fruit extract, this gentle toner hydrates skin while regulating skin’s pH. It also works as a shield to keep other skincare ingredients from evaporating.

Have you tried exfoliating with PHAs?

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Photo: Ana-Maria Nichita on Unsplash, Respective brands

Peaceful Dumpling Beauty Editor and creator of Bisou du Jour, Mary Hood Luttrell lives with her husband in Corpus Christi, Texas. Mary is a freelance writer and writing and blogging consultant. A lover of whole foods, Mary delights in learning new ways to prepare vegan dishes. Mary also enjoys reading and writing poetry, art journaling, running, and practicing yoga and ballet. Follow Mary on her blog Bisou du Jour, Instagram and Pinterest.


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