What are Amino Acids? | Amino Acids for Skin

What Are Amino Acids?

Amino acids are small molecules that serve as the basic building blocks of proteins; much larger functional molecules that are so vital to every cell of our bodies (including skin cells).

There's a group of 20 different amino acids which are important for our general health. Most of these can be made by the body, but some cannot, and instead must be obtained from our food or dietary supplements: These ones are called 'essential' amino acids and there are 9 of them.

Depending on its specific function, a protein will be made up of any number or combination of those 20 building blocks. They might provide structural support, such as keratin, collagen or elastin, or perform essential chemical reactions if their function is as an enzyme.

Sometimes, you'll also see mention of peptides. These are simply compounds consisting of two or more amino acids, but not an entire protein. Think of them as protein fragments. They're often used in topical skincare formulations when the complete protein (e.g., collagen) would be too large to penetrate the skin. Peptides also provide anti-ageing benefits and strengthen the skin moisture barrier, and they also improve skin elasticity, helping the skin look firm and youthful.

Frequently Asked Questions About Amino Acids

Amino acids are the basic building blocks of proteins and peptides (which are effectively just fragments of the whole protein).

Amino acids or peptides can be used in a skincare routine to promote the synthesis of structural proteins like collagen and elastin, giving skin greater firmness and elasticity. Some amino acids are useful as humectants, so can work as moisturising factors in the skin. These work well together with ceramides and fatty acids to support the skin’s moisture barrier and boost hydration. And some amino acids are effective antioxidants, with anti-ageing benefits that help protect the skin from the effects of environmental free radicals.
In skincare terms, amino acids and peptides can be applied topically in most skincare products, such as moisturisers, serums and cleansers. As small molecules, they are generally easily absorbed into the skin, where the complete protein might not be.
Amino acids and peptides are generally suitable for all skin types, including sensitive skin. However, they are quite a targeted ingredient, so it's important to match the amino acid(s) used to the concern you want to address. For example, some are beneficial for dry, sensitive skin, others for boosting collagen or elastin production.
Yes, amino acids can be used on the body.
They certainly can! Some amino acids make a natural pairing with other ingredients: for example, amino acids that are useful as humectants work well together with ceramides, hyaluronic acid, and fatty acids to support the skin’s moisture barrier and boost hydration. Likewise, collagen-boosting amino acids or peptides complement skin cell renewal and collagen-building effects of retinol.

Having said that, not everything makes a good pairing - for example, the effectiveness of alpha hydroxy acids (AHAs), such as glycolic acid or lactic acid, may be inhibited by using amino acids as part of the same routine.
The blemishes that occur with acne-prone and oily skin occur when pores become blocked by a combination of dead skin cells, sebum (natural skin oils) and bacteria.

As we've discussed, some amino acids may help support the skin's moisture barrier, boost hydration, or boost skin protein production. For example, lysine (one of the 9 essential amino acids) has been shown to help build collagen in the skin. However, although you may come across claims that lysine can help acne-prone skin or target breakouts, there's actually little evidence to support this.