Hair Care Tips & Styling Ideas

What Are Amino Acids? Plus, the Benefits for Skin, Hair & Nails

woman wearing workout clothes

Behind water, the next largest component in our bodies is protein. Protein is only produced when there are sufficient amino acids present. Amino acids are what many experts have deemed the “building blocks” of the body. To be the building blocks of anything is a powerfully fundamental gig, and amino acids are just that—powerful and fundamental.

They play a crucial role in our body’s metabolic processes as they relate to growth, repair, transportation, storage and functionality. Amino acids directly affect a multitude of elements, including our muscles, organs, digestion, blood and brain activity—just to name a few!

Because these acids are so vital and complex, we caught up with expert, Christie Marino, certified health coach through the Institute for Integrative Nutrition and Level 2 CrossFit trainer, to break down amino acids for us.

3 Types of Amino Acids 

There are 20 amino acids that form protein in our bodies and they are split into three categories: essential, nonessential and conditional. According to Marino, amino acids are responsible for pretty much every chemical reaction in our bodies.

1. Essential Amino Acids 

The acids that must come from our diet. There are nine essential amino acids and they are histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan and valine.

2. Nonessential Amino Acids

Acids produced by our bodies, including alanine, asparagine, aspartate and glutamine.

3. Conditional Amino Acids

Those that can usually be produced by the body except under specific health-related circumstances (such as auto-immune deficiencies, stress, young/old age) and they include arginine, cystine, tyrosine, glycine, ornithine, proline and serine.

What Do Amino Acids Do?

Marino says our bodies must have protein in order to produce new muscle tissue and connective tissue. “Our body runs on protein,” she says, “so amino acids are responsible for muscle growth, but it’s important to remember you cannot enter into the world of fitness and expect results without a healthy diet.”

Nutritionally speaking, meats, dairy products, eggs, legumes, nuts and cereals are particularly high in protein, but Marino says as long as we’re eating whole foods, we’re at least partially restocking our protein supplies.

“Since all of our proteins are made up of just 20 amino acids, the differences between the thousands of unique proteins are simply in the sequence of those amino acids,” she adds. “We have specialized molecules that know which amino acids to put together in what order to make a certain protein.”

Marino took a second to describe each one of our cells as a picky Wolfgang Puck—they must have every amino acid needed, every ingredient present, before it will even think about starting to make a protein.

“Let’s just say, our cells are smart and can improvise and convert some amino acids into others if they are missing an ‘ingredient,’” she tells us. “However, the nine essential amino acids must be eaten, and when you combine foods, like beans and rice or pasta and cheese, you do get all of the essential amino acids. And it’s extremely important that you do!”

Benefits of Amino Acids: Hair, Skin & Nails

Not only are amino acids vital to maintaining our physique and keeping a healthy diet—they also contribute to benefits for our hair, skin and nails.


Marino explains that because the amino acid, methionine, can build connective networks—it supports the strength and structure of our hair. Methionine is an essential amino acid and can be found in meats, nuts, beans and dairy products.

Additionally, arginine and glutamine have immense benefits for hair growth. Arginine can stimulate hair growth by creating a stronger passageway to get blood to the root. Glutamine is produced naturally, but as we age we produce less and less. “Glutamine and methionine contain sulfur, supporting optimal hair growth,” says Marino.


Arginine and Glutamine also support cell growth and renewal when it comes to skin, but Marino says glycine, leucine and proline are all directly involved in collagen production, hydration and many anti-aging skin concerns. “Collagen is a protein, and we need amino acids to build protein,” says Marino. “They can only offer immeasurable benefits.”


“Similarly to our hair, arginine opens that passageway for our blood, creating healthier circulation and support to the root,” says Marino. “This all comes back to protein. There are beauty products and supplements that are taking advantage of amino acids, and I encourage everyone to utilize that opportunity.”

Freelance Writer

Megan Kiger

Megan Kiger is a writer, a worrier and an infamous sleeper. She is happiest in the fall with an abundance of sweatshirts, tacos and rom-coms on repeat. You will catch her often at the gym or in deep overanalyzing thought. If she could offer any words to live by: never stop learning.