Here’s Everything You Need to Know About How to Use Lactic Acid
Main image – Ohlamourstudio/Stocksy
Have you ever heard of or read the words ‘lactic acid’ in relation to skincare and been too embarrassed to ask what it is?
We’ve all been there. Only my embarrassment is usually related to astrology or food groups. (What can I say? They’re both completely baffling.)
I don’t blame you. With so many skincare ingredients with the word ‘acid’ at the end, it’s no wonder this one’s tipped you over the edge. From glycolic and hyaluronic to alpha hydroxy and beta hydroxy…make it stop!
Don’t worry, this article’s got you covered. Because not only do our experts have an explanation on what exactly lactic acid is, how you’ll benefit from it, why it’s the perfect acid for beginners, and how to use it too.
So, with help from Dr Geeta Yadav, Rachel Lee Lozina and Nina Prisk, you’ll be a lactic acid lecturer in no time.
Now, if someone could please explain what a lunar eclipse is and why I need to harness the power of the moon, I’d really appreciate it.
What is lactic acid?
Lactic acid one of the gentler AHAs, or ‘Alpha Hydroxy Acids,’ a group of acids commonly used in skincare to chemically exfoliate skin. Other common AHAs include glycolic acid, citric acid and mandelic acid and you’ll find these acids in everything from cleansers to toners, serums and masks.
“Lactic acid is a gentle alpha-hydroxy acid derived from milk,” explains Dr Yadav. “It helps loosen the glue-like bonds that hold dead skin to the surface,” Lozina adds.
Lactic acid has been shown to be less irritating to skin than glycolic acid, one of its most commonly-used fellow AHAs, in multiple studies.
“Because it has a larger molecule size than other AHAs, like glycolic acid, it tends not to be as irritating, making it a great choice for those with more sensitive skin or those who are new to chemical exfoliants,” Dr Yadav confirms.
Its gentleness is actually what makes lactic acid my favourite chemical exfoliant and it’s one of the few AHAs that I personally can use regularly throughout the week without irritating my skin.
What are the benefits?
Ok, but what can it do for your skin?
It’s great for combatting dry skin too, according to Lozina. “It has a lot of hydration benefits as well which makes it great for a mature or dry skin type,” she says. “It also helps improve skin texture and colour.”
Prisk continues, “lactic acid can also help to stimulate collagen production, reducing fine lines and wrinkles.”
I can also vouch for its benefits since my skin is consistently brighter and smoother when I remember to use my lactic acid toner.
Who shouldn’t use it?
Whilst lactic acid is one of the gentler acids for sensitive skin though, whether your skin will tolerate it will depend on the scale of your sensitivity. “Those with extremely sensitive skin, like individuals with rosacea, may find that it’s still too potent for their skin,” warns Dr Yadav.
Since some AHAs have been shown to increase skin’s sensitivity to the sun, Lozina recommends that anyone who’s regularly in the sun shouldn’t use lactic acid either.
“People who are chronically outside like surfers, gardeners, etc, who are exposed to the sun all day should also not use it,” she says.
How do you apply lactic acid?
Like with any skincare products, always read the label before using a lactic acid as each product will have its own directions.
For example, serums with lactic acid will generally go after your cleanser and before your moisturiser. “Normally you don’t need to wash off lactic acid after applying it directly to the skin after cleansing,” confirms Prisk.
PRO TIP: Much like your moisturiser, some experts recommend you apply lactic acid in serum form onto damp skin to use the benefits to their full potential.
What percentage should you pick?
Prisk says that lactic acid comes in lots of different concentrations, generally between 5% and 10%. “While higher concentrations (higher than 10%) are effective, they’ll also increase your risk of irritation,” warns Dr Yadav though.
“I recommend sticking to concentrations of 10% or below to get the benefits you’re looking for without negative side effects.”
Introduce it slowly, like you would with something like retinol. “Start at the lowest amount and acclimate from there and make sure you use a lot of moisturiser to combat dryness,” Lozina says.
How often should you use lactic acid?
“A weaker-strength lactic acid can usually be used daily, whereas stronger formulations only a couple of times a week, maximum,” Prisk advises.
And, like with many other acids, you can over-do it. “Using lactic acid too much can risk causing over-exfoliation which can negatively impact the skin’s natural pH barrier,” she continues.
“If your skin becomes dry, itchy or irritated when you’re using it, then you’re probably using it too much.”
Equally, if you’re using other strong skincare ingredients like retinol alongside lactic acid you should reduce your use to once or twice a week. You can learn more about how to exfoliate while using retinol in our guide here.
Lactic acid mostly benefits those with dry or mature skin who are looking for a gentle way to exfoliate. But people wanting to start using a chemical exfoliant that’s mellower than something like glycolic acid are likely to also benefit.
Watch your percentages – stick to 5% and below if you’re a beginner. And don’t overdo it. Just because lactic acid is one of the gentler acids, doesn’t mean you shouldn’t use it carefully. Treat it like any other powerful ingredient like retinol and your skin will thank you.
Meet the experts
Dr. Geeta Yadav is a board-certified dermatologist and founder of FACET Dermatology.
Rachel Lee Lozina is a New York State Licensed Aesthetician, Laser Technician and Oncology Aesthetician and Founder of Blue Water Spa in Oyster Bay, NY.
Nina Prisk is an aesthetic nurse prescriber and owner of Update Aesthetics Cosmetic Clinics, both in London’s Harley Street and Cornwall. Prisk is a lecturer and ambassador for global industry brands. She advocates for the importance of a multi-faceted regime that incorporates both injectables and skincare products. Qual: RGN, INP, BSc, MSc.