If you’ve heard the term lactic acid before, you likely come from one of a few select groups of people – athletes, dairy producers, and skincare lovers. That’s a pretty wide-ranging group, and it’s because lactic acid occurs naturally in both our bodies (building up in our muscles during a workout) and in dairy products. Lactic acid is what gives dairy its signature tangy taste and is believed to be one of the reasons that Cleopatra bathed in milk – because it also has some pretty unique benefits for the skin! As those passionate about skincare may already know, lactic acid also acts as an exfoliant, moisturizer, cleanser, and much more. It’s also found in a number of products used to treat skin conditions, including eczema, psoriasis, and rosacea.
There’s a lot to know about this special alpha hydroxy acid, including what it is, how it can benefit your skin, and how you can use it. Keep reading for a deep dive into everything you need to know about lactic acid in skincare, including if products containing lactic acid are right for you.
What Is Lactic Acid?
Lactic acid is an organic acid and one of many alpha hydroxy acids (AHAs). It can be produced by our bodies, occur naturally in food like raw milk, or be created synthetically in a lab. In the human body, lactic acid is chemically produced when your cells break down carbohydrates for energy (this is often referred to as lactate). It’s one of the reasons that runners will often walk on tired legs after a long race, such as a marathon – to help move the lactate out of their legs. Because of this, most people believe that they’re only producing lactic acid during a tough workout, but this isn’t the case! Anything that makes your body consume more oxygen than usual can cause the breakdown of carbohydrates and lactic acid production. While muscle and red blood cells make the most lactic acid, it is also found in many other tissues throughout the body – including the GI tract, the brain, and the skin. If you’ve heard bad things about lactic acid, it’s likely due to research from the 1980s that concluded it caused muscle soreness. Thanks to more advanced research methods, we now know this isn’t true. That’s enough sport science for now, but the point is, lactic acid is not a bad thing!
Aside from the human body, lactic acid also naturally occurs in dairy products. It isn’t a dairy product in and of itself but occurs because lactic bacteria ferments lactose in the milk, naturally creating lactic acid. While all milk experiences this reaction, goat milk is a preferred source of lactic acid due to its higher concentration. Who knew the humble goat could produce such a valuable asset? This might even be a reason that people have for centuries bathed in goat’s milk... while they might not have always understood the science behind it, they could see and feel a benefit from soaking it in.
Fortunately, a milk bath is no longer necessary to reap the benefits of lactate acid. Now that we know more about where it comes from and have debunked some myths, let’s dive into everything that it can do for you and your skin!
It’s a Natural Exfoliator
One of lactic acid’s unique qualities that makes it a sought-after skincare ingredient is that it is the gentlest of the alpha hydroxy acids. Acids are typically known for their ability to break things down, and lactic acid is no exception – but it can do this gently, without causing harm. In the case of your skin, this means that lactic acid acts as a natural exfoliator, gently removing old cells from the skin’s surface. It does this by dissolving the bonds that hold these cells together, allowing them to be washed away from the skin’s surface and revealing new, bright cells underneath. Studies have found that this stimulates and increases cell turnover, meaning your skin is shedding old cells and replacing them with new ones faster. The result is a brighter complexion and softer skin.
It's a Natural Moisturizer
You might not have expected this, but lactic acid is also a natural moisturizer! Chemically, it’s a humectant, meaning water molecules are naturally attracted to it. When applied to the skin, lactic acid naturally draws moisture in, hydrating the cells. Additionally, it provides a benefit that other AHAs can’t match. Remember above when we mentioned that lactic acid is also found in the skin? This is because lactic acid is a component of our body’s natural moisturizing factor or NMF. The NMF is a blend of compounds produced by the body that holds onto moisture and is the skin’s way of helping us stay hydrated! But washing or bathing with harsh cleaning products can reduce the levels of NMF in the outer layers of the skin – so lactic acid helps naturally replenish the NMF with each use. This can also help re-balance the microbiome, especially for those with sensitive skin.
It Improves the Skin’s Appearance
Aside from exfoliating and moisturizing, lactic acid has several more qualities that improve the skin’s appearance. As it exfoliates, it also stimulates collagen production, which keeps skin firm, and elastin, which keeps skin tight. Both of these help soften fine lines and wrinkles. Its moisturizing abilities also slow and prevent the development of further fine lines, though it can’t help deeper ones. All of these can contribute to healthier skin and a bright, vibrant appearance.
Dermatologically, lactic acid has been used to treat a variety of skin conditions. Studies have found that it is effective in treating eczema, psoriasis, rosacea, and many more. It is also effective at treating keratosis pilaris, which often appears on the backs of arms, by dissolving bumps.
Where Can I Find Lactic Acid?
After reading this far, you might feel the impulse to run to the nearest store and purchase a lactic acid product for your skin! We understand – the benefits are pretty amazing. But it’s important to consider the source of your lactic acid, the concentration, and the unique qualities of your skin, such as its sensitivity level before you begin using it yourself.
Today’s lactic acid in skincare typically comes from two sources – naturally occurring lactic acid, such as what is found in goat’s milk, and synthetically produced lactic acid, which is typically created in a lab. Synthetic lactic acid is typically created specifically for use in skincare products.
Because lactic acid can be so beneficial, most commercial products don’t just use lab-made lactic acid, but they include the lactic acid at a much higher concentration than it occurs naturally. More is better, right? Not exactly. At higher concentrations, lactic acid can cause some undesirable side effects, especially for those with sensitive skin. These can include redness, burning, dryness (a side effect of irritation), itchy skin, and even swelling. Because of this, commercial lactic acid products are not typically recommended for those with sensitive skin.
Fortunately, those with sensitive skin, or those who want to avoid lab-made ingredients don’t need to miss out on the benefits of lactic acid! Because lactic acid occurs naturally in goat milk, goat milk skincare products are a great alternative to commercial lactic acid products. The lactic acid in goat milk, and therefore goat milk products, is present at an effective, but gentle concentration that won’t irritate the skin (though we always recommend checking with your dermatologist before using a new product on sensitive skin or a skin condition).
Lactic acid can provide numerous benefits for the skin – so it’s no secret that the people of ancient times were onto something by taking milk baths. Thanks to its moisturizing, cleansing, and exfoliating qualities, lactic acid can improve the overall appearance of the skin, while also contributing to healthier skin overall and a more balanced microbiome. Fortunately, there are several ways to nourish your skin with this powerful AHA now, so a milk bath isn’t necessary! But, if you want to avoid synthetic ingredients or powerful concentrations that could cause irritation, it might be best to seek out products made with goat milk, the dairy product with the highest effective, but gentle, natural source of lactic acid. As usual, be sure to carefully read product labels to ensure that goat milk is a primary ingredient, and no other irritants are added – like artificial fragrances or colorants, which can also irritate sensitive skin.
If you’re looking for natural and effective goat milk skincare products, you might be interested in our goat milk soap, lotion, lip balms, and other products. At Madd House Hill, we believe in the power of goat milk and use 100% farm-fresh goat milk as a core ingredient in each of our products, along with moisturizing and sustainable oils, and therapeutic-grade essential oils for an all-natural scent. Our all-natural philosophy is something we are extremely proud of, and don’t plan to change! Many of our customers who have previously experienced skin sensitivity and irritation with commercial products have found great success when switching to our natural options.
Until Next Time,
Madd House Hill