Amino Acids, Peptides & Proteins Oh My! What is their Role in Hair & Skin Care Products?
While you've certainly heard of protein and perhaps even have faint memories of learning about amino acids and peptides in science class perhaps you wonder why they are included in skin and hair care and if they actually work.
Let's take a closer look at what amino acids and peptides are and how they are used in skin and hair care.
Proteins are used to create the framework of our bodies (think skin, hair, muscles etc.) and make enzymes -- the protein "workers" that carry out necessary reactions in the body such as digest food or catalyze reactions to build muscles or turn digested food into energy.
Proteins are made from the building blocks of typically 40+ amino acids that are linked together to form a polypeptide , which folds into a 3D shapes to create proteins. Like beads are the building blocks of a bracelet or lego or duplo bricks are the building blocks of a model or a car or rocket ship, amino acids are the building blocks of proteins.
Peptides on the other hand are small chains of amino acids on the order of 20 to 30 amino acids. In the body peptides can have a variety of functions, such as a hormone affecting the endocrine system to regulating the immune system, and many can have significant skin-smoothing effects and help reduce the loss of firmness of the skin.
In their paper Cosmeceuticals and peptides, authors Zhang and Falla state that "the majority of chemical reactions, biological responses, and regulatory processes are modulated in some part by specific amino acids sequences." 1
They suggest peptides then have created a "diverse new field of modulating molecules applicable to dermatology and skin care industries." 1
In the Formula Botanica post "A Guide to Natural Peptides" they suggest including peptides in formulations because they can increase skin hydration, enhance elasticity, texture, and moisturization, offer protective and anti-aging functions, demonstrate skin renewing properties, and are well suited in products for the face such as creams or serums. 2
One question that arises with peptides (as will many ingredients used in skin and hair care) is that of penetration. In general size and charge are thought to affect penetration of molecules into the skin.
However the mechanism for how peptides work in not fully understood. Zhang and Falla suggest in the case of aged or dry skin peptides may have an easier time penetrating, especially with the addition of penetration enhancers. So it may be best to focus on how individual peptides tend to work. 1
Peptides can be synthesized in a lab or derived from natural sources. Two common synthetic peptides thought to boost collagen and elastin production are palmitoyl tripeptide-1 and pamitoyl tetrapeptide-7.
In natural skin care hydrolyzed plant and animal proteins and extracts from organisms such as yeast are sources of natural peptides (hydrolyzed is when a large protein is enzymatically broken down into smaller pieces).
Some examples include: hydrolyzed or plant based collagen, hexapeptide-11 derived from yeast, and a variety of hydrolyzed proteins and amino acids from nature such as silk amino acids, pea protein, wheat protein, quinoa protein, lupin protein, elastin, or rice protein for example.
I'll touch on examples of a few proteins, peptides, and amino acids I use in my formulations and studies and their benefits. I personally prefer to work with naturally derived peptides and amino acids. They are readily available and in general suitable for natural or organic skin and hair care.
Silk Amino Acids: I use silk amino acids in several hair care products I formulate for a wholesale client as well as in Goat Milk Face Cream. Hydrolyzed from pure silk fibers, silk aminos are known to penetrate into the upper layers of skin and into the hair shaft and have excellent moisture binding ability. Which means they draw moisture into these areas. This results in more soft manageable hair and more supple, smoother skin. Yes please! Silk aminos are used in shampoos, conditioners, hair treatments, as well as products for the body and face.
2. Plant Derived Keratin: Keratin is a major component of hair, skin, and nails. It can support strength, elasticity, and shine in hair, reduce frizz, and improve its comb-ability. While the keratin monomer is only 18 amino acids long it is still considered a protein and it forms strong fibrous bundles that make up hair, skin, nails, in humans and horns and hoofs in other mammals. Its arginine content contributes to supporting hair strength. It is a great addition to hair care products and the plant derived version is vegan. I use keratin in a leave in conditioner I create for a wholesale client as well as a 3 in 1 shampoo and body wash and a new shampoo bar that is currently in developmental stages. Keratin is ideal for shampoos, conditioners, leave on hair treatments, and hair styling products.
3. Hydrolyzed Rice Protein: Rice protein is thought to improve hair volume, manageability, fortify the hair, and add natural shine. On the skin it improves moisture retention to improve skin hydration and elasticity. Hydrolyzed rice protein contains both cationic (positively charged) and anionic (negatively) charged amino acids. The positively charged amino acids bind to the hair while the negatively charged amino acids repel the fibers creating a sense of volume. As I develop a few new products such as a shampoo bar and a volumizing conditioning foam I plan to incorporate rice protein. Rice protein is used in hair care products such as shampoos, conditioners, styling agents, products for the scalp , moisturizers, masks, and washes.
4. Hydrolyzed Elastin: This is another protein I use in our Goat Milk Face Cream. Elastin is a large protein that gives the skin and connective tissue its flexible qualities. It degrades over time but this can be slowed with healthy lifestyle choices. While its large size inhibits its penetration into the skin or hair, when applied topically it acts as a film former and offers moisturizing, smoothing, and conditioning effects. It can help protect the skin and hair and improve hair strength and protect it from damage. Elastin is often used in anti-aging skin care products as well as shampoos, conditioners, balms, and pomades. The natural version is derived from marine sources such as fish thus it is not a vegan ingredient.
5. Hydrolyzed Lupin Protein: White lupin is a rich source of vitamins, minerals, and glutamine rich peptides. glutamine is thought to increase cell growth while the vitamins and minerals help support healthy skin and scalp. Hydrolyzed lupine protein is also thought to act to inhibit enzymes that degrade collagen and elastin, thus helping support healthy skin. It is added to anti-aging formulations and shampoos, conditioners, and other hair products.
I hope you've enjoyed this brief overview of proteins, peptides, and amino acids in skin and hair care. Do you have questions about a particular natural peptide or protein in skin care or hair care? Comment below or contact Tricia.
Zhang, L. and Falla, T, (2009), Cosmeceuticals and Peptides, Clinics in Dermatology, 27, 485-494
Formula Botanica Blog Website, The Formulators Guide to Natural Peptides, accessed on 8/30/21 from: https://formulabotanica.com/natural-peptides/