Amino Acids for Skin
Amino acids are the building blocks of both peptides and proteins, and each has a specific role in skin care. Amino acids maintain skin’s hydration, texture, resilience, and an overall supple, healthy appearance.
It’s not a stretch to say that amino acids are indispensable, for our skin and elsewhere in our body. That’s why we've chosen several amino acids to play a supporting role in many of our skin care products.
What Are Amino Acids?
There are many amino acids, but most scientists agree that there are 20 that are important to our health, divided into two types: essential and non-essential. The “non-essential” term doesn’t mean that those amino acids aren’t important; rather, it means that your body can make them on its own, so it’s not “essential” for you to get them elsewhere, such as from food or supplements.
“Essential” amino acids, on the other hand, are essential because they must be obtained from foods or supplements; a deficiency in even one of them can result in health problems.
There are nine essential amino acids: histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine. The best food sources of these amino acids include animal protein (seafood, beef, poultry), followed by animal by-products such as eggs and dairy. Vegan sources of essential amino acids include quinoa and soy/tofu. Beans and nuts also provide some amino acids, but not all of the essentials.
The 11 non-essential amino acids, which the body can make on its own, include alanine, arginine, asparagine, aspartic acid, cysteine, glutamic acid, glutamine, glycine, proline, serine, and tyrosine. Several of these are also known as “conditional” amino acids, meaning they’re made by the body, but only under certain conditions, such as when we're under stress or ill.
Each amino acid plays a vital role in maintaining our health as well as the appearance of our skin. But, just how do amino acids work on and within skin?
How Amino Acids Benefit Skin
Amino acids are naturally present in skin, as part of what’s called our natural moisturizing factors (NMFs). Within skin’s uppermost layers, amino acids work as conductors, orchestrating an incredibly complex “concert” that allows our skin to thrive and to stay hydrated.
One of the ways they do this is by working in harmony with aquaporins (the body’s water transport system) to move moisture throughout skin. Because of this, the primary benefit is that the amino acids help maintain skin’s smoothness and hydration, something they also do when applied via skin care products.
There also are more surprising benefits of these small, but potent, skin care heroes: Some amino acids work as antioxidants; however, most of them are believed to play an even greater role by helping skin create more of its own antioxidants, such as glutathione. Topically applied amino acids help strengthen skin’s natural defense system, making it less likely to show signs of aging from environmental damage.
Interestingly, research has shown that synthetic amino acids often have greater hydrating ability than animal- or plant-derived amino acids. Because many amino acids are animal-derived, this is encouraging news if you prefer to avoid such ingredients, as we do.
The Best Amino Acids for Skin
Although all the amino acids mentioned above play a role in creating and maintaining smooth, healthy, younger-looking skin, a few also have more specialized roles, which make them even more desirable to see in skin care products:
- Arginine plays a role in repairing visible skin damage.
- Histidine has antioxidant ability and can soothe skin.
- Methionine neutralizes damaging substances before they can harm skin.
- Lysine helps visibly firm skin’s surface by reinforcing its supportive elements.
- Proline, leucine, and glycine diminish the look of fine lines and wrinkles.
How Amino Acids Work with Peptides
All amino acids included in skin care products work in combination with other ingredients that are also part of skin’s NMFs, including our favorites glycerin, ceramides, various peptides, and hyaluronic acid. The amino acids work particularly well with peptides—that’s why we include them in our Peptide Booster, a targeted product that significantly increases skin’s hydration as it reduces signs of aging.
Amino acids are truly versatile ingredients that complement other beneficial skin care ingredients, from antioxidants to plant extracts to omega fatty acids. Without question, topically applied amino acids improve all skin types, and can benefit all ages, especially if your goal is to prevent or diminish signs of aging.
References for this information:
Current Medicinal Chemistry, January 2018, pages 324–335
International Journal of Cosmetic Science, February 2017, pages 72–82
Amino Acids, November 2015, pages 2,265-2,278; and June 2012, pages 2481–22489
Life Sciences, August 2015, pages 36–41
Biophysical Journal, April 2014, pages 1701–1709
Bioscience Reports, March 2014, ePublication
European Journal of Dermatology, April 2013, pages 195–201
Journal of Advanced Research, July 2010, pages 169–177
Journal of Cosmetic Dermatology, June 2007, pages 75–82
About the Experts
Paula Begoun is the best-selling author of 20 books about skincare and makeup. She is known worldwide as The Cosmetics Cop and creator of Paula’s Choice Skincare. Paula’s expertise has led to hundreds of appearances on national and international radio, print, and television including:
The Paula's Choice Research Team is dedicated to busting beauty myths and providing expert advice that solves your skincare frustrations so you can have the best skin of your life!