What are acids and why should I put them on my face?

3:31 PM Moi Sanom 0 Comments


What are acids exactly?

Hydroxy acids are exfoliants that speed up the cell turnover rate in your skin which in turn makes dead skin shed faster.
Your skins natural turnover rate starts at 1 week as a child, around 3 weeks in your 20s and then slows down significantly as you age.


Not shedding a proper amount of dead skin can result in rough, scaly, discolored skin which may look more lined and might even be more prone to breakouts and other kinds of blemishes.
Using an exfoliating product helps take off that layer of dead skin and reveals fresher, smoother and healthier skin beneath.


What types are there and how do they work?

The two types of Hydroxy acids are Alpha (AHA) and Beta (BHA)

Types of Alpha Hydroxy acids that are also found in food are: 

  Glycolic acid – Sugar cane
  Lactic acid – Milk
  Malic acid – Apples and Pears
  Citric acid – Citrus fruits
  Tartaric acid – Grapes
  Mandelic acid - Bitter Almonds

The only type of Beta Hydroxy acid is Salicylic acid.

The biggest difference between AHAs and BHAs is that AHAs are water soluble and BHAs are lipid/oil soluble. Which makes BHAs more suitable for oily skin types.

All types of Hydroxy acids are chemical exfoliators but every one of them has different attributes as well which makes them unique and more suitable for certain skin concerns than others.

I will call it Ghouloxy acid! For the natural undead complexion!
I will talk about the 3 wider used acids and also about a little outsider acid that in my opinion will be the next popular one on the school grounds of skin magicians.

Even though AHAs are water soluble they actually have hydrating properties which makes them great for drier skin types. They help significantly to decrease sun damage and hyper pigmentation scars. By reacting with the upper layer of the epidermis they weaken the binding properties of the lipids that hold dead skin cells together reducing the appearance of wrinkles and rough skin.
After prolonged use they also might stimulate the productions of collagen and elastin.

Glycolic acid is one of the most used AHAs on the market, followed by Lactic acid, these two AHAs penetrate deeper into skin than others. When using Glycolic acid there can be a higher risk in getting skin irritations, since the molecules are much smaller. Lactic acid is often preferred to be used for people with sensitive skin since it penetrates less deep and thus having a smaller chance of irritating skin.

The best concentration of daily AHAs are between 5 and 8 percent so look for them on second or third place on your ingredients list. They also need to have a PH of 3 to 4, since their efficiency decreases if the PH is higher than 4.5.

Mandelic acid is my favorite AHA!
It is more difficult to find but it has a unique super power.
It combines the properties of both AHAs and BHAs into an acid that should make everyone happy!

Just as happy as watching Vincent Price ramble!
Mandelic acid has the same properties as other AHAs of course, such as rejuvenating photo aged skin, eliminating PIH, improving fine lines, and  having a visible brightening effect due to its exfoliation powers.
Mandelic acid also has antimicrobial and antibacterial properties with which it has the ability to treat inflammatory acne and with its unique antibiotic action it can even help reduce acne in people who don’t respond to other acids or antibiotic treatments. Since it has a larger molecular structure than Glycolic acids, it is less irritating but actually more efficient. Which makes it suitable for sensitive skin types, even the ones that couldn’t tolerate other acids, and perfect for people that have rosacea since it also has anti-inflammatory properties.

It can penetrate into pores like Salicylic acid, only not as deep, while still releasing debris by increasing cell turnover and loosening blackheads for easier extraction. It helps keep sebaceous filaments at bay and even works well for people who did not have desired results with other acids.
It is not know to cause de-pigmentation, which makes this also suitable for darker skin types.
Maybe now you know why I love the power of Bitter Almonds more than my other acid buddies.

Not yet so far!
As I mentioned above, BHAs are lipid soluble which means that they are able to fully dissolve in oils, which makes them better at penetrating pores and more suitable for oily and acne prone skin types.
Just like AHAs they decrease the appearance of wrinkles, roughness and sun damaged skin. Since Salicylic acid contains anti-inflammatory and anti bacterial properties dermatologists often prefer BHAs to AHAs since they are less irritating. That also makes them suitable for sensitive, reddened skin or people with rosacea.

BHAs work wonderfully at lower concentrations of 1 or 2 percent at a PH of 3 to 4. If you are looking for a product that contains BHA try to find it towards the middle or end of the ingredients list.

The side effects of acids may be skin irritation, redness, burning, itching and increased sun sensitivity. Darker skinned folks may experience a higher risk of scarring pigment changes.
That is why patch testing with more pigmented skin is very important!


How much more photosensitive will you be?

The top layer of dead skin has naturally some sun protection properties, so when you remove it with acids or a physical exfoliant, you decrease the natural sun protection abilities of your skin.
Which means it is even more important to use sunscreen everyday.

A wonderful look but not necessary when using acids thanks to SPF

Will my face burn off when using acids?

Acids only eliminate the top layer of skin that is formed by already dead skin cells.
It will not remove functioning and healthy cells. It doesn’t penetrate deep enough into the skin to do so and it is also the reason why it doesn’t “erase” tattoos since the ink is in the deeper levels of the skin.
There can definitely occur minor acid burns, but these are more likely to happen when using a high dose of acid which can be found in weakly or monthly treatments and acid products for professional use only.

Will my skin purge if I use acids?


The only products that may cause “purging”, which is basically worsening of your skin after introducing new cosmetics, would be acids and retinol since the exfoliation can cause your cells to push the blockages from the inside out to the surface. The products don’t actually create new spots rather than revealing them faster than they would have by themselves. Any break outs you experience from other type of products are not “purging” but probably a reaction to the product itself.
I recommend discontinuing use since your skin does not seem to be happy about it.
The “purging” you may get from using acids should stop after about 2 to 4 weeks, if you observe it for longer than that you might want to see if there may be other reasons for your breakouts.

Why and who should use them?

Anyone who suffers from hyper pigmentation, acne, rosacea, that is concerned with aging or has too sensitive skin for physical exfoliation, should probably consider using some kind of acid.
These are often one of the more powerful and practical actives to help you get the skin you want.

Are they better than physical exfoliation?


Since Hydroxy acids are less abrasive, they are often recommended for people with break outs.
The friction from manual exfoliation tends to break open active acne, causing tiny skin wounds and spreading bacteria. This also applies to people without acne.
Not only can some scrubs be harsh and cause your skin to develop micro tears, you can also easily over exfoliate and irritate your skin.

Some skin types are not recommended to use manual exfoliators such as people with rosacea, eczema, very dry or sensitive skin, and as mentioned above, people with active acne.

It is also important to mention that most physical exfoliants use microbeads, which are incredibly harmful for our environment since they end up in our water and enter our food chain.
Samplehime wrote a very interesting article on the subject.

How to use acids?

Since using acids can indeed produce some side effects it is recommended to not just slap products containing them on like any other moisturizer.
They should be introduced slowly to let your skin adapt to them first before using them more often. You need to keep in mind that everyone is different and always proceed with caution while observing and listening to what your skin has to say.

Introduce it slowly, going overboard is hardly worth it!

This is also the method that I use and the one that my husband follows.
I am happy that I started introducing acids slowly into our routine, especially since it turned out that Johnny Clyde actually can’t tolerate all types of acids, and this reduced possible damage that could have happened otherwise.

First decide what acid you think suits your needs best, always start with the smallest concentration and work your way up.
Wash your face and Tone to achieve the natural PH of your skin faster.
Since acids need a low PH to be most effective, using a toner helps the acids work better.
Apply whichever type of Acid product you decided on, be it a gel, a toner or a lotion.
Wait 15 to 30 minutes for it to work its magic.
You don’t have to do this step of course, but applying more products right after the acids will raise the PH of your skin and thus stopping the Acid powers.
Afterwards you can proceed with your routine as usual.

It is possible for your skin to go through some changes when using acids, which means that you might have to adjust the type of products you are using, such as introducing a more gentle or hydrating moisturizer. You should already be using sunscreen of course, but if you are not it is important to do so on a daily basis when you start using acids.
Otherwise you might undo all the acid magic with sun exposure.
I usually don’t use acids when I know I will be spending more time in the sun, like on a holiday or when I go to the beach (not that I do that anyway).


When you start using acids it is recommended to only use it once every 2 or 3 days for at least a week or more to see how your skin reacts.
If all is well, you can shorten the wait time between applications until you use it every day.
If your skin can’t handle this, it is absolutely OK to only use Acids as often as your skin is comfortable with.
I sometimes use them once a day or even twice when my skin was really bad but not until I already used them for over a month.
Your skin is not happy when it is overly red or pink without going back to normal, itchy, tender and painful.
If you get any of these symptoms, stop using your acid treatments and wait for your skin to normalize itself for a few days before you reintroduce them again, slowly.
You might be using them too often, at a too high concentration or simply an acid your skin doesn't like.

As I mentioned before, Johnny Clyde can not tolerate most Acids.
He has tried Glycolic and Salicylic acids which make his skin feel tender after just one application and after repeated applications it becomes pink and even painful.
He does tolerate weekly Lactic acid treatments and a daily Mandelic acid cream.

What his face looked like
What he will describe if you ask him
And to be honest some people don’t have as good results with some acids as others.
I have noticed that even though I can tolerate all of the ones I have tried, they do not really help me with sebaceous filaments, and even though BHAs are supposed to be specifically useful to remove them, they did not help in Johnnys case either.
Mandelic acid has been a miracle worker though and the improvement has been dramatic!

I highly recommend taking before and after pictures!
The improvement while using acids can be very slow and often not noticeable by ourselves.
It will probably take at least 4 weeks to see any improvements and up to six months to see a drastic change.
But if you are patient you will be rewarded!
I actually didn’t notice hardly a difference until I saw my own before and after pictures.

Benton contamination before and after
Call me impressed!

Now you might want to know which products contain BHAs or AHAs.
I decided to write a little list of some that I have either used or heard positive things about.
I need to mention though, that some of the most popular and hyped about Brand that produces products containing acids is Paula’s Choice. I have used both the 1% BHA and 8% AHA gel and even though they have worked well, they were not especially better than other products I have tried. So you might want to either start with cheaper options if you are an acid newb or order some of their samples before shelling out all that moolah!


I also wanted to mention that it is a waste of money to purchase cleansers with acids.
They have too high of a PH for the acids to be stable and they need time to actually exfoliate your skin.
Which it doesn't have when you wash it off immediately.
If you use the cleanser to exfoliate, it will unfortunately not work, but if you like its cleansing abilities, than keep it of course!

I will post the products with a rating from 1-10 so you guys know which ones I liked best.

Avene Triacneal
Glycolic acid
PH: 3.5
Surprisingly hydrating, only a little amount is necessary, spreads easily, good for any skin type, especially dry

Pharmaceris Sebo Almond peel 5%
Mandelic acid
PH: 3.5
Not hydrating, dries very fast, very gentle, helps eliminate acne and sebaceous filaments, perfect for sensitive skin or people who hadn’t had great results with other acids

Paula’s Choice 1% BHA gel
Salicylic acid
PH: 4
Very thin liquid gel, doesn’t dry out skin, only very little product necessary, expensive but lasts for a long time

Paula’s Choice 8% AHA Gel
Glycolic acid
PH: 4
Very thin liquid gel, doesn’t dry out skin, only very little product necessary, expensive but lasts for a long time

Lactic acid treatment
Lactic acid
PH: 1
Very strong, needs to be used with caution, can be mixed into lotions for a milder exfoliation, great to use on the body, lasts a long time, can only be used as a monthly treatment


Products I haven’t tried but heard good things about are:

Mizon AHA and BHA Daily Clean Toner, Mizon AHA 8% Peeling Serum

Make Up artists choice Acid products

Silk Naturals toners

Other Paula’s Choice acid treatments

Have you used acids yet? Which ones and what is your favorite?
Feel free to ask any more question on the subject in case I missed a point!

Who can resist Jeff Goldblum?

 I want to point out that the Gifs and Memes used in this post are of humorous and sarcastic nature and your face will not burn or melt off. There is no actual pictures of Hydroxy acids and their negative effects on skin shown. If you use daily exfoliants there is a very low risk of getting a chemical burn, which usually only occurs with stronger treatments and chemical peelings.  
Unless you are allergic you shouldn't get more than redness and tenderness. 
You should still be cautious if you have never used chemical exfoliators before.