What are AHAs?
Alpha Hydroxy Acids (AHAs) a class of chemical compounds that can be either naturally occurring or synthetic. Many are derived from natural sources such as sugar cane, corn, apples and grapes and are used in cosmetics to exfoliate the skin. This is called chemical exfoliation. Acids play an important role in beautifying the skin. They speed up the normal process of skin cell regeneration and sloughing, resulting in a more even and smooth complexion. They work by breaking down the bonds that hold the dead skin cells together at the surface of the skin.
Benefits of AHAs
Skin naturally sheds off the dead skin cells, but as we age, this process slows down and can contribute to a dull, dry, uneven complexion. The more sun damage one has had, the thicker the dead top layer of the skin becomes (as a means of protection), and can contribute in a dull and rough complexion. Therefore, the added support of chemical exfoliants will help to remove the damage, resulting in a more even and smooth complexion. AHAs are preferred for sun-damaged and dry skin because they exfoliate the skin’s surface, and have the added benefit of also improving moisture content in the skin.
What They Do:
Unclog pores
Reduce lines and wrinkles
Smooth the skin
Reduce brown spots
Increase product penetration
Increase collagen production
Improve moisture in the skin
The Two Most Used AHAs – Glycolic and Lactic Acid
Glycolic Acid
Glycolic acid is derived from sugar cane and is the strongest AHA. It has the smallest molecular size compared to other AHAs, so it is able to penetrate the skin deeper and quicker, thereby increasing shedding of the dead skin cells at a faster rate. Glycolic acid brightens, firms, and smooths the skin, while reducing blemishes, fine lines and dark spots in the skin.
Lactic Acid
The next AHA that deserves great attention is lactic acid. Lactic acid is a hydrating AHA commonly derived from sugar-rich foods such as milk, fermented corn starch and beets. When compared to glycolic acid, lactic acid shows greatly reduced irritation because it has a larger molecular size and penetrates less deeply into the skin. It is a great choice for those with sensitive or dry skin, or those just starting out using AHAs. Lactic acid brightens, smooths, and evens the skin, while also making it look firmer. It helps reduce the appearance of fine lines, wrinkles, and dark spots. Furthermore, it helps to increase the moisture binding functions in the skin, making it a great choice for dry, dehydrated skin.
Strength Matters
The strength of the acid used, the final ph, as well as the constancy of the product all determine how effective the product is on the skin. The thinner the formula, such as a toner or gel, the faster the penetration of the acid into the skin. This can be beneficial for thicker or more oily skin. Dry and sensitive skin will benefit more from a cream based formula to buffer the potential irritation from the acid. In general, a product containing 5-10% acid, with a ph between 3-4, will result in a non-irritating and effective product. The maximum percentage that I would recommend for home use is 15%. Going above that will most likely cause irritation, dryness and an impaired skin barrier.
I recommend my Refining Lotion which contains 10% natural fruit acids and skin conditioners. It is a gentle, yet effective exfoliating lotion that can be used on all skin types.
How to Use
If you’re just starting out to using acids on the skin, begin by using a product containing them every other night. Then, as the skin builds tolerance, slowly increase usage. It is important to not over use acids and pay very close attention to how your skin is responding. If your skin becomes dry, flaky, or irritated, you’ll want to back off use until your skin feels balanced again, then resume.
What to Expect
It’s normal to feel slight tingling immediately after applying a product containing an AHA. This could last for up to 10 minutes. If it continues, remove it from your face and use a lower strength product. As your skin gets used to using acids regularly, tingling should subside quickly after application. At this point you could optionally go up in strength. Slight redness can be expected too, but should should also subside quickly. If it doesn’t subside after 15-30 minutes, remove the product and use a lower strength next time.
When to use AHAs
AHA’s are recommended for nighttime use as they increase sun sensitivity. However, a face wash containing AHAs can be used in the morning because it is not left on the skin for a long period of time. The longer AHAs sit on the skin, the deeper they work. Creams and toners should be reserved for night use, and cleansers can be used in the morning.
Pick One AHA Containing Product
I recommend picking one form of an AHA containing product and sticking with that, because it can get easy to overuse acids if you have it in multiple products (cleansers, creams, toners). Start slowly, using it twice per week. Then, if tolerated, use every other night. To keep your skin balanced and give it time to regenerate, I recommend using AHAs no more than 4 times a week.
Use Sunscreen Daily
Lastly, beware that all AHAs make the skin more susceptible to sun damage. They exfoliate off the dead protective layer of your skin. This makes it extra sensitive to sun damage for up to 7 days after use. Hence, it is imperative that you wear sunscreen daily while using any AHA. AHAs help reverse visible and invisible damage done by the suns ultraviolet rays, but if you don’t also use a sunscreen daily, you risk canceling the positive effects of the AHA and experiencing further damage on top of it.
What Not to Use it With
If you use a Retinol containing product, do not use AHAs at the same time as Retinol. Pick one to avoid irritation. Alternating AHAs with Retinol will produce great results. Using AHAs combined with l-ascorbic acid (Vitamin C) can be irritating for sensitive skin. If you use products with l-ascorbic acid use them during the day and AHAs at night.
In Conclusion
AHAs are a beautiful treatment for the skin as they help to shed damaged skin cells, smooth the surface of the skin and increase product penetration. Professional peels containing a higher strength acid can be preformed monthly to increase skin regeneration. Prep the skin with home care products containing glycolic or lactic acid for at lease two weeks before receiving a professional peel. This will prepare the skin for the higher strength acids and minimize irritation.
*Always remember to use a sunscreen during the day and use AHAs a maximum of 4 times a week. Skin will benefit from using hydrating and nourishing creams while using AHAs to replenish the skins moisture. Used correctly, AHAs are beneficial at achieving healthy and bright skin.