Most of us suffer from clogged pores, fine lines, dark spots, and dull complexion from time to time. Chemical exfoliants found in over-the-counter cleansers and lotions can help with these issues - and one that’s growing in popularity is lactic acid. Lactic acid is found in milk and comes from the fermentation of lactose, a carbohydrate (don’t worry, you don’t have to count it in your calorie journal). There are also some vegan sources such as fermented corn starch, beets, and other foods rich in carbohydrates. Peels and serums often contain synthetic forms of lactic acid even though it's naturally found in the skin.
Lactic acid is an alpha-hydroxy acid (AHA) that dates back to ancient Egypt (the story is that Cleopatra used to bathe in soured milk to keep her skin youthful). AHAs, if you aren’t familiar with them, are water-soluble compounds that are organic and booming in popularity due to their unique benefits for the skin. But it stands out from other AHAs in that it also naturally hydrates the skin. Lactic acid is a great choice for people with sensitive skin and is generally regarded as safe and effective for removing unwanted discoloration in dark skin - where other acids can cause problems.
Exfoliants typically work by loosening dead skin cells to improve the skin’s appearance and allow deeper penetration of other actives. Further, they speed up cell turnover - not just shedding dead skin cells but stimulating new cell production.
What are the major benefits of lactic acid?
- Itbrightens the skin (helps with dullness) partially by shedding the outer layer of skin. This is known as a superficial peel. It removes old, dead, and dull cells on the skin's surface by dissolving the bonds that hold them together (i.e., exfoliation). It works as deep as the hair follicle, so it smooths out bumpiness.
- It may be helpful in reducing acne. Exfoliation helps remove dirt, oil, and debris from pores reducing blackheads and whiteheads.
- It can fade sun spots/age spots the same way (shedding the outer skin layer).
- It improves the skin's natural moisture factor (NMF) which hydrates the skin. This can lead to plumpness and a decrease in fine lines.
- It's antimicrobial. That’s why certain topicals for eczema, psoriasis, and rosacea often contain lactic acid.
- It works on all skin types and is one of the best choices for people with sensitive skin.
Lactic acid improves the skin's natural moisture factor (NMF) which hydrates the skin. This can lead to plumpness and a decrease in fine lines.
Which products contain lactic acid?
Lactic acid is available in different forms making it easy to incorporate into most skin care regimens. Cleansers are popular for those of us still battling acne. Creams and lotion versions usually contain moisturizing ingredients like hyaluronic acid and ceramides to prevent dryness. On the other hand are serums, more concentrated and for the advanced user.
Masks are the strongest over-the-counter form of lactic acid - most people will experience mild peeling when using them. Spas and dermatologist offices usually offer professional-strength lactic acid peels, stronger than all of the other lactic acid options. It’s still amongst the more gentle of peels. When you compare it to glycolic acid or trichloroacetic acid.
HOW TO USE LACTIC ACID SAFELY & EFFECTIVELY
Even though it’s gentle, sometimes it can cause tingling, redness, swelling, a burning sensation, itching, peeling or sensitivity to the sun.
Even with gentle exfoliants, it’s important to start slowly. First and foremost read the product instructions and make sure you’re aware of whether the product is a leave-on product or a rinse-off product. Using cream as a face wash won’t give your skin enough contact with the lactic acid, and using a face wash as a mask might cause too much peeling.
KNOW YOUR SKIN TYPE
Some people with very sensitive skin report that lactic acid can irritate. When picking your first product consider one with a low percentage of lactic acids, such as five percent. If you haven’t used an acid before then start with three times a week and gradually build up to nightly (lactic acid is usually applied at night). If you notice any irritation, stop using the product or slow down to twice a week. Once you’re used to how a product affects your skin you can increase the usage when your skin has better tolerance.
APPLY YOUR SKINCARE PRODUCTS IN THE RIGHT ORDER
So that products can be absorbed properly and not be blocked by the prior layer, regimens are typically applied from thinnest to thickest. The order typically goes toner, then serum, then moisturizer, then oil. The acid can be applied at whatever step is appropriate based on this. A serum would go after any toners and before any moisturizers.
Consider alternating nights (retinol Monday, lactic acid Tuesday, retinol Wednesday and so forth) in order to reduce the risk of irritation. Also, wash your face the morning after you use acids to rinse away shedded oil and debris.
DO A PATCH TEST
One idea for people with sensitive skin is to perform a patch test on the inner portion of your upper arm, or just below your chin to see if you have any type of reaction. Some irritation is normal when starting. If it becomes extreme, discontinue use or talk to your dermatologist for the next steps.
If you’re also using prescription skincare medication check with your board-certified dermatologist before using lactic acid. It may not be appropriate for you. In particular, retinoids, retinols, other AHAs, and harsh scrubs are likely to cause irritation when used with acid exfoliants.
SPF IS YOUR BFF
Finally, make sure to include sunscreen and moisturizer as part of your routine when using exfoliants. These ingredients can cause sun sensitivity: sloughing off the outer layer of skin cells can increase the risk of sun damage. To balance the dryness, apply moisturizer. Leaving your skin without moisturizer might paradoxically stimulate the overproduction of oil. Looking for a good sunscreen? Check out our chemical vs mineral sunscreen guide here.