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WHAT IS PHA?: A GUIDE TO PHAS IN SKINCARE

Polyhydroxy acids (PHAs) are a popular skincare ingredient that have a wide range of benefits including moisturisation, renewal, and enhancement of the skin barrier function. PHAs can also be better for sensitive skin than other commonly used chemical exfoliants, such as AHAS and BHAs, as they have a larger molecular structure so don’t penetrate as deeply into the skin.

Here, we’ll cover exactly what PHA is, how you can use it in your skincare routine, and how PHAs differ from BHAs and AHAs.

In this guide:

  • What is PHA?

  • Why are PHAs a good alternative for sensitive skin?

  • How to use PHA

  • Why does AVEENO® Skin Renewal feature gluconolactone (PHA)?

  • PHAs FAQs

What is PHA?

PHAs – or polyhydroxy acids – are chemical exfoliants which are known to be relatively gentle.

What does PHA do?

PHAs are known for being non-irritating and gentler to skin, hence their use in body and skincare products as a gentler chemical exfoliant.

Examples of common PHAs used in skin care products include:

Aside from their gentle exfoliating properties, PHAs also provide moisturising properties when compared with AHAs , and help to enhance the skin barrier function.

Is PHA an exfoliant?

Yes, PHA is a chemical exfoliant with multiple benefits, including:

  • Being non-irritating, so it can be used on sensitive skin types

  • Renewing your skin’s surface

  • Helping to enhance the skin’s barrier function, which in turn can increase the skin’s resistance to chemical challenge

Why are PHAs a good alternative for sensitive skin?

PHAs are a good alternative for sensitive skin because they:

Are non-irritating

PHAs are non-irritating, which makes them a great choice for those with sensitive skin.

Help create a smoother, softer layer of skin

A PHA, like gluconolactone, helps to improve cell turnover. The agent works by removing dead skin cells and smoothing the surface of the skin, which supports the skin’s renewal process to generate a softer new skin layer.

Gentler on the skin

PHAs tend to be less sensitising and gentler on the skin than other chemical exfoliants. Therefore, they may be better suited to sensitive skin types who don’t tolerate other chemical exfoliants as well.

Why is PHA better than AHAs and BHAs for sensitive skin?

PHAs are a type of hydroxy like AHAs (alpha hydroxy acids) and BHAs (beta hydroxy acids). All three can be used in skincare products to provide a range of similar benefits, but PHAs are less likely to irritate the skin.

The molecule size of PHAs is larger than AHAs, meaning they don’t penetrate the skin as deeply or sink into the skin as quickly, resulting in less potential irritation and sensory discomfort to sensitive skin. PHAs also provide additional moisturising properties compared to AHAs.

If your skin tolerates it, you may want to consider using a serum specially formulated with a mix of PHAs and AHAs and/or BHAs to help deliver improved results. But for those with sensitive skin, it may be best to use just products with PHAs.

How to use PHA

PHAs are found in many different skincare products, such as cleaners, moisturisers, and toners. If you’re looking to add polyhydroxy acids into your skincare routine , but are unsure how to use PHA, you can follow these steps:

Start with a patch test

Before you apply a new PHA product, it can be wise to carry out a patch test to see how your skin reacts. Simply apply a small amount to your forearm and leave for 24 hours then check for any potential signs of irritation.

Build up your tolerance gradually

When introducing a PHA product to your skin, you can use it on three non-consecutive days before gradually increasing how often you use it.

Integrate PHA into your daily skincare routine

PHA products can be applied morning or evening after you’ve washed your skin. If you’re using an exfoliating PHA product, like a peel, be sure to follow with a serum and moisturiser to help hydrate and protect the skin barrier.

PHA products, like the AVEENO® Skin Renewal range, can be used as part of your existing daily regime. For example, you can use the AVEENO® Wash-off Skin Renewal Gentle Body Scrub in the shower, and the the scrub in the shower and the AVEENO® Skin Renewal Smoothing Cream or AVEENO® Skin Renewal Firming Lotion after.

Be mindful of which ingredients you combine it with

Paring PHA products with another product that contains ingredients such as glycerin, hyaluronic acid, and ceramides can help amplify the hydrating properties of PHAs.

However, there are some ingredients that may be best to avoid when using PHA products. These include PH-sensitive products, such as vitamin C. If you use vitamin C products, consider applying these in the morning and PHA exfoliating products at night to minimise potential irritation.

Why does AVEENO® Skin Renewal feature gluconolactone (PHA)?

Gluconolactone – which is a naturally occurring component of the skin – is the PHA used in the AVEENO® Skin Renewal range, and it’s naturally derived.

Your skin naturally sheds dead skin cells, but certain factors can cause this process to slow down – such as ageing, and sun damage. As skin cells build up, the skin can appear dull and rough. Gluconolactone acts as an exfoliating agent that helps improve cell turnover by removing dead skill cells – thus promoting skin renewal to generate a smoother and softer skin layer.

The AVEENO® Skin Renewal range features three key products:

Each product contains naturally derived PHA ingredients, which, alongside oat flour – a nourishing ingredient which helps to lock in moisture in the skin – work together to bring the best result and support your skin’s microbiome.

PHAs FAQs

What percentage of PHA is in the AVEENO® Skin Renewal range?

PHA is in AVEENO® Skin Renewal products at the following percentages:

  • 2% in the scrub

  • 6% in the smoothing cream

  • 4% in the firming lotion

Can I use PHA every day?

When you’re just starting to use a new PHA product, it may be best to use it on three consecutive days each week to test for sensitivity. You can then build up your tolerance and use certain PHA products – such as cleansers, moisturisers, and toners – daily. Other PHA products, like masks, are typically intended to be used less frequently, such as once a week or once a month.