If you are new to skincare, have you ever wondered why people are suddenly raving about acids in skincare? If you’re curious what is AHA, BHA and PHA and which acid is best and safest, you’re in the right place!
The name “acid” can be quite intimidating, but don’t let that scare you. Once you find the right one for your skin, chemical exfoliators like AHAs, BHAs and PHAs can create a HUGE difference in the way your skin looks.
Chemical exfoliation helps remove dead skin cells and improve skin tone and texture. However, since these acids differ a lot, you need to make sure to pick the right one accordingly to your particular skin type and concerns.
Here’s everything you need to know about acids in skincare. Let’s get started!
AHA Vs. BHA Vs. PHA – Key Differences
AHA is the short for alpha hydroxy acids, BHA – beta hydroxy acids, while PHA means poly hydroxy acids.
The key differences among these chemical exfoliators are as follows:
pH level: AHAs and BHAs have lower pH (ranging from 3-4) whereas PHAs have a pH of 7.
Gentleness: PHAs are the gentlest on the skin as compared to AHAs and BHAs.
Comedogenicity: BHA is the least comedogenic (tending to cause blackheads a.k.a comedones) among all these acids.
Action: Though they are all chemical exfoliators, the features that set them apart are that AHA acts as a humectant (moisturizer), BHA has anti-inflammatory properties and PHA has anti-aging properties.
Skin type: AHA is great for dry, sensitive, and combination skin types whereas BHA works wonders for oily and acne-prone skin types. PHA is excellent for sensitive skin types or those who are new to acids in skincare.
Solubility: AHAs and PHAs are water soluble whereas BHAs are oil soluble.
Light sensitivity: AHAs are photosensitive i.e. sensitive to light, hence they should always be followed by sunscreen, and it’s best to use them in the nighttime routine. On the contrary, BHAs and PHAs are not photosensitive.
Skin penetration: AHAs are able to penetrate the skin’s surface, BHAs are able to go deeper and unclog the pores, but PHAs, due to their molecular size stay on the skin’s surface.
What Is A Chemical Exfoliation & Why Is It So Important?
Chemical exfoliation is basically using certain chemicals namely the AHAs, BHAs and PHAs to remove the dead cells from your skin, which build up on the skin’s surface making it look dull and rough.
The chemical exfoliants speed up the natural cell renewal process by breaking down dead skin cells.
This can transform skin from dull to radiant as it helps improve uneven skin texture, fade fine lines and wrinkles, reduce acne scarring, blemishes, and hyperpigmentation, unclog pores, reduce blackheads and whiteheads, and balance oil production, according to the type of exfoliator used.
This results in smooth skin with a healthy glow.
Adult skin needs regular exfoliation, otherwise it’s more prone to acne and blackheads, because the pores get clogged with dead skin cells, dirt and excess sebum. The other effect may be visible signs of premature aging.
PRO TIP: There are products for exfoliation that combine a few different acids, for example: insanely popular The Ordinary AHA BHA Peeling Solution. It’s quite harsh on the skin which means you need to soothe it afterwards. In this article I share my tips for what to use after AHA BHA peel to relieve the irritation. Make sure to read it before trying out these acids – whether you’re exfoliation newbie or a pro!
Everything You Need To Know About Alpha Hydroxy Acids (AHAs)
Alpha hydroxy acids (AHAs) are water-soluble exfoliants hailing from natural origins (sugar cane, apples, and milk).
They work by dissolving the dead skin cells to promote natural shedding and reduce buildup on skin surface. This improves rough skin, refining the skin texture and tone while minimizing signs of aging such as wrinkles.
The most well-known AHAs are:
If you have normal, combination, or dry skin type you can benefit from AHA acids.
Derived from sugarcane, the most popular alpha hydroxy acid – glycolic acid, exfoliates dead skin cells while being gentle on the skin. It also boosts collagen production, which helps to reduce wrinkles along with softening fine lines.
If you have dry, normal or combination skin types, glycolic acid is a good choice for you.
Since AHAs act as humectants, they are awesome for dry and mature skin types. It also helps fight the signs of UV damage on sun-damaged skin and reveals a brighter complexion.
Since glycolic acid can penetrate the skin really well, it is mandatory to slather your face with SPF after using it to avoid sun damage. I recommend to use it in your nighttime routine.
Also, glycolic acid is the most potent AHA. So it’s best to start with a product having low concentration and slowly build it up in your skincare routine, as you skin adjusts to it.
Another famous AHA is lactic acid, which is derived from milk and sugar cane. It is a tad bit milder than glycolic acid, making it a better choice for those who find the latter too harsh for their skin.
Apart from exfoliating properties, lactic acid has the ability to combat dryness by increasing ceramides (the lipids that make up the skin barrier).
It is also considered the gold standard for people with Keratosis Pilaris (chicken skin).
The result? Hydrated plump skin with improved skin texture.
Lactic acid is beneficial for all skin types but especially for dry, mature, and sensitive skin types.
The most gentle alpha hydroxy acid is mandelic acid, which is naturally found in almonds. It is considered the best acid for acne, pigmentation, and aging.
Its ability to prevent acne breakouts, fade acne scars and signs of sun damage makes it really a popular choice for people with acne-prone skin, as well as sensitive and dry skin types.
Found in apples, Malic acid is great for exfoliating dead skin cells, improving uneven skin tone, lightening dark spots, cleansing pores, and smoothing away congestion while keeping the skin hydrated.
It is great for people with acne-prone, dry, and sensitive skin types.
Hailing from citrus fruits (lemons, oranges, berries), this skincare acid helps to balance pH and lighten pigmentation. Besides having antioxidant properties, citric acid works as a natural astringent, removing excess oil and cleansing pores.
It is a great choice for people with oily skin and specific skin concerns such as hyperpigmentation, dark spots, etc.
If you have delicate skin you should only use it in low concentration so it does not irritate your skin.
Present in tamarind and wine grapes, tartaric acid is an antioxidant and also has anti-aging properties. It can gently exfoliate the skin while fighting signs of aging and dull skin.
It is suitable for any skin type.
Benefits Of AHA
Smooth skin texture: AHAs remove the rough skin and improve the texture of the skin.
Moisturized skin: As AHAs are humectants, they keep the skin moisturized.
Gentle on the skin: AHAs have large molecules, so they cannot penetrate the skin too deeply. This renders them gentle on the skin.
Fighting signs of aging: AHAs address skin problems such as blemishes, fine lines, and wrinkles. Due to enhanced collagen production and antioxidant properties, they make the skin appear healthier and fresh.
Improved skin tone: Since AHAs speed up the shedding of dead skin cells, they reveal bright skin and hence a better tone.
Reducing acne: AHAs like mandelic and citric acid have acne-fighting properties that reduce acne breakouts. The increased cell turnover prevents dead skin cells from causing acne.
Diminished Pigmentation: Due to their exfoliating properties, AHAs fade away hyperpigmentation and dark spots.
Everything You Need To Know About Beta Hydroxy Acids (BHAs)
Beta hydroxy acids are able to penetrate the skin deeper and unclog pores. As they are oil soluble, BHAs can bust the oil, dirt, keratin plugs, and gunk sitting in your pores. The result? Good riddance to clogged pores!
This group of exfoliating acids includes
Willow bark extract
BHAs reveal the best results for acne-prone and oily skin types. People with dry or sensitive skin might experience irritation though, so it’s advised to use it sparingly.
Salicylic acid is the most popular beta-hydroxy acid. As it contains anti-inflammatory properties, salicylic acid is beneficial to treat acne, blackheads, white bumps, and pimples.
It reduces the appearance of enlarged pores and even addresses skin concerns such as psoriasis, calluses, and warts.
Benefits Of BHA
Treating acne: The anti-bacterial salicylic acid fights acne-causing bacteria and reduces acne breakouts. It is best for spot treatments.
Bye bye clogged pores: Due to their oil solubility, BHAs unclog pores and remove all residue.
Oil production control: Salicylic acid reduces excess oil by slowing down the production of sebum. This makes it really great for people with oily skin.
Minimizing appearance of pores: Cleaning out the pores helps with reducing the appearance of enlarged pores and prevents future blackheads.
Fighting inflammation: Salicylic acid is beneficial for people with active acne as it reduces inflammation and redness.
Addressing other skin problems: Salicylic acid can also treat calluses, milia, warts, corns, and more.
Smooth skin’s texture: By sloughing off dead cells, BHA yields smooth skin and improves the texture.
Sun protective abilities: Among the many skin benefits of salicylic acid is its sun protective abilities, unlike glycolic acid.
Everything You Need To Know About Poly Hydroxy Acids (AHAs)
Poly-hydroxy acids (PHAs) are the gentlest exfoliating acids. Due to their large molecular size, they do not penetrate the skin and hence exfoliate the dead skin without causing any irritation. This makes them the best option for people with dry, dehydrated, and sensitive skin.
They are often used in skincare products that gently exfoliate the skin and add moisture to the skin, as PHAs are humectants.
This poly hydroxy acid is derived from milk and offers gentle exfoliation while reducing signs of aging, dark spots, and sun damage, thanks to its antioxidant characteristics.
If other acids do not suit your skin, this is definitely the one for you.
Found in corn, this PHA has humectant, antioxidant, and antimicrobial properties. It provides chemical exfoliation while fighting free radical damage and boosting the skin’s hydration levels.
Derived from dairy products and animal milk, galactose boosts collagen synthesis while fighting signs of aging. It is great for people with skin issues like atopic rosacea or eczema.
Benefits Of PHA
Moisturizing the skin: As PHAs act as humectants, they support the skin’s moisture barrier and keep the skin hydrated.
Gentlest acid exfoliant: PHA offers the most gentle exfoliation, when compared to AHA and BHA.
Great for sensitive skin: PHAs are game changers for people with sensitive, dry, or dehydrated skin, including people with rosacea and eczema.
Antioxidant: PHAs fight free radical damage and protect the skin against pollution.
Collagen booster: Polyhydroxy acids enhance the production of collagen. This helps in softening fine lines and dark spots, making them a suitable choice for mature skin.
AHA, BHA, PHA – Potential Side Effects
The usual side effects of these exfoliating acids are skin irritation, itching, stinging, burning, redness, and in the case of AHA, sunburn. Usually, PHA has almost mild to zero side effects. BHA can cause dehydrated flaky skin in individuals with dry skin.
If the skin doesn’t go back to normal and side effects persist even after a few weeks, maybe the ingredients aren’t okay for your skin. Consulting with dermatologist is always best before you start your journey with skincare acids.
Differences Between AHA Vs. BHA Vs. PHA – Comparison
Here’s my in-depth of these two types of acids.
PHAs are the most gentle exfoliating acids. Due to their high molecular weight, they cannot penetrate deep into the skin. On the other hand, AHAs like glycolic acid can cause irritation due to their penetrative ability. Salicylic acid can cause irritation and dehydration for dry skin types, as they can penetrate the pores even deeper.
AHA and PHA are water-soluble, which means they cannot break down the oil that clogs pores and leads to acne. On the other hand, BHAs are oil soluble so they easily remove the oil clogging up the pores, while also reducing sebum production.
3. Not For All Skin Types
AHAs are best suited for dry and combination skin types, BHAs are amazing for acne-prone and oily skin types and lastly, PHA is the best option for people with dry or sensitive skin or those who are new to acids in skincare.
4. How They Work
Apart from the common action of chemically exfoliating away dead skin cells, the trio differs in their exclusive actions.
Glycolic acid can brighten the skin while adding moisture to support the skin barrier. Salicylic acid fights acne-causing bacteria and reduces inflammation, whereas PHAs fight the signs of aging due to their antioxidant characteristics.
5. Skin Penetration
AHAs can penetrate the top layers of the skin. This is why it is advised to start with low concentration to minimize the risk of irritating your skin.
BHAs go the deepest as they are oil-soluble and remove all the gunk sitting inside your pores.
On the contrary, PHAs, due to their biggest molecular size, cannot penetrate the skin and act only superficially. This is the reason why they are the gentlest of all acids.
6. Light Sensitivity
AHAs are photosensitive whereas BHAs and PHAs are not.
Hence it is advised that you use sunscreen after AHA because it can cause sunburn if you don’t. Even better, always try to use AHA during your nighttime routine to avoid sun damage.
7. AM Or PM routine
Now you may be wondering if it’s best to use acids during your morning routine or evening skincare regimen.
Since AHAs are photosensitive, it is recommended to use them in the evening skincare routine.
Meanwhile, BHAs and PHAs are good to use in either morning or evening routine, as they do not make your skin more sensitive to the sun. In fact, salicylic acid has sun protective abilities.
AHA Vs. BHA Vs. PHA – Similarities
They reduce and prevent acne breakouts.
They exfoliate the skin and reveal bright and healthy skin.
They minimize the appearance of pores.
They fight signs of aging such as fine lines, wrinkles, blemishes, pigmentation, dark spots etc.
They transform skin from dull to glowy.
They boost collagen production.
They improve the skin’s texture and tone.
Which Is Better: AHA Or BHA Or PHA?
AHAs are best for people with normal, mature, dry and rough skin, whereas BHAs are best for oily and acne-prone skin types. PHAs are best for people with sensitive, dry or dehydrated skin or those who are just starting to use acids in their skincare.
Since AHAs make your skin photosensitive, it is a must to use sunscreen after applying AHAs. Otherwise, you might risk getting your skin sunburnt.
AHA Vs. BHA Vs. PHA – FAQ
Here are a few questions you might have in your mind about AHA BHA and PHA. Once you get the hang of it, these acids can really transform your skin.
Are PHA As Effective As AHA?
PHAs are the gentler alternatives to AHAs. Though they are not as potent as AHAs, they get the work done without irritating the skin.
Can I Use AHA, BHA And PHA Together?
Yes, you can use AHA BHA, and PHA together. Many skincare products have all 3 acids in their ingredients.
However, always remember to use BHA in lower concentrations as compared to AHA.
Can I Use AHA, BHA And PHA Everyday?
No. It is advisable to use these acid exfoliants 2-3 times per week. Otherwise, you might risk your skin being irritated or flaky. So you shouldn’t use AHA, BHA and PHA everyday, because it can lead to over-exfoliation.
Does AHA, BHA Or PHA Cause Purging?
Yes, AHA, BHA, and PHA can cause purging, especially if you’re new to acid exfoliation. It usually lasts for 4-6 weeks as the skin adjusts to the new skincare routine.
The purpose of this article is informative and entertaining. It’s not a substitute for medical consultation or medical care. The author of this article does not accept any responsibility for any liability, loss or risk, personal or otherwise, incurred as a consequence, directly or indirectly, from any information or advice contained here. Safety should be your priority.
Pictures with YouAreBeautie logo belong to YouAreBeautie.com and were taken by the owner of this website. All these images are copyright-protected.