Peptides, what are they? Chances are you’ve already seen the advertisements and all the brand new skincare products that boast of containing peptides. And probably, you've already purchased and tried a product that contained these (in)famous peptides. And yet, you know next to nothing about them, and several questions and mild worries keep sloshing in your head. Just what are peptides? Are peptides harmful? Can peptides help you reduce sebum, get rid of acne, or alleviate scars? What do peptides even do? Can you use peptides for the skin? Lots of questions, but very little answers.
And, if answers are what you're looking for, well... You’ve come to the right place. We’ll answer those questions - and more.
You’re not crazy to be confused about peptides. The answer is both elegant and confusing. It’s simple, but it’s also complicated - mainly because understanding peptides requires a bit of previous knowledge.
I take it that you’re familiar with what proteins are. Being one of the few essential nutrients for the human body, proteins act as the building blocks of our body’s tissues. From the skin, the bones, the muscles and the dozens of inner organs, proteins build it all.
But what are proteins made of? Well, here’s the answer to your question: peptides.
Imagine, if you will, a large bundle of molecules. You won’t be far from the real thing if you imagined something resembling a ball of yarn. That tangled ball of yarn is a protein. There is an uncountable number of different proteins, and some of them make up the tissues in our bodies.
Now, imagine if we took that ball of yarn (protein) and began disentangling it. Every time we pulled a string, a section of it would come loose at certain points, and break off. That section - a smaller portion of the molecular yarn comprising the protein - is called a peptide. The protein (the ball of yarn) was made up of dozens, or even hundreds of shorter, or longer strings - these being the peptides - all tied together, connected to one another.
So, proteins are the complex molecules that build our bodies. While peptides are the complex molecules that build the proteins in turn. Super clear, right?
But wait. What are the peptides themselves made out of?
Well, to answer that question, we’ll need to zoom in deeper. If we take a single string (or, a peptide) of that ball of yarn (or, a protein), and look closer… We will notice that the strings themselves, or the peptides, are comprised of smaller subsections. These smaller sections are actually called amino acids. Amino acids are the building blocks of proteins, but they can also arrange themselves in shorter, smaller structures - peptides.
Amino acids play hundreds of crucial roles in our bodies. From regulating the construction of protein in our bodies to keeping our organs healthy and helping our bodies regenerate, we could literally not exist without amino acids. If proteins are the building blocks of our bodies, then amino acids are the building blocks of the building blocks.
So far, there is some debate regarding the number of existing amino acids. In nature, scientists have identified more than 500 amino acids that form plants or animal life. However, when it comes to the human body and our DNA, the number is far smaller. A commonly accepted number of human-related amino acids is 20, although some scientists think there are at least 21 or 22. At any rate, amino acids are organized into two groups: essential amino acids, and non-essential amino acids.
Essential amino acids have to be consumed from either plant foods, or animal foods. These essential amino acids then help our bodies construct the rest of the 20-something non-essential amino acids. Not only that - some essential amino acids, like L-lysine, have very specific skincare properties.
Depending on whom you ask, there is a third category of amino acids, called conditionally-essential, which are produced, but not really necessary. However, all of this means that in order to be healthy, we need to supply our bodies with essential amino acids, which will then form peptides, which will then - I hope you can see where this leads - form proteins.
And when we’re talking about our skin’s health and skincare in general, which protein comes to mind? Collagen.
And which molecular structures link together to create proteins? That’s right. Peptides.
By now, I hope things make more sense, and that you can already take a stab at why peptides are becoming used in the skincare and beauty industries. But let’s see how good your intuition is.
In the previous section, we outlined the fact that amino acids construct peptides, and that peptides (and amino acids) construct proteins. And that proteins were the building blocks in our bodies, performing a variety of important functions. Well, then, the question arises: what should we do if we wanted to have more of a certain kind of protein?
Well, the answer would be - add more peptides. Or conversely, add more amino acids to be transformed into the desired peptides. However, simply introducing more amino acids doesn’t mean that our bodies will produce the peptids, and in turn, the proteins that we desire. So, if we wanted to increase the production of a certain kind of protein in our body, our best bet is to supply it with the exact, specific peptides that will build the exact, desired protein. Simple, right?
But just how do peptides achieve this?
Well, aside from building proteins, peptides also function as biological messengers, signaling our bodies to do important things. Our bodies naturally produce every form of peptide necessary (that is if we supply it with enough essential amino acids). Peptides are within every human cell, where they arrange themselves to build enzymes, produce hormones, and even attach themselves to other molecules to become an energy source. In a way, peptides roam around the body, moving from cell to cell, like messages in a bottle. Whichever molecule reads the message, receives a signal tailored to them, and harnesses the peptide’s benefit.
But back to the practicalities of skincare. What does a topically applied peptide, over the surface of your skin, do for your skin and body? If it even does anything?
Well, it kinda does. Scientists aren’t really sure how peptides manage to pull that off since human skin was deemed impermeable to compounds with a molecular weight of above 500 Daltons. However, exceptions exist (for example the allergy to latex, which has an MW of over 50,000), calling into question the so-called “500 Dalton Rule.” The topical application of peptides is one of the exceptions to the rule since studies show that peptides do, indeed, cause improvement to the skin. (Although it technically shouldn’t, since the MW of peptides is well above 500, which means it’s not supposed to be resorbed.)
Understandably, this leaves scientists scratching their heads. Just how are peptides able to achieve this? How is a substance that cannot penetrate the human skin able to influence its lower layers into producing collagen, and therefore, improving the skin?
Well, there is a prevailing hypothesis. If you recall, peptides seem to have some sort of biological signaling property. It seems that when our skin cells come into contact with peptides, their very presence seems to mean that more collagen needs to be produced. So, the cells of the skin’s surface receive those signals from the peptides applied on top of it, convey it down the line to the deeper cells in the body. This, in turn, boosts the production of collagen and elastin - two crucial proteins in maintaining skin elasticity and health.
So, how do peptides work? They signal the body to begin producing collagen, elastin, and other proteins that help our skin. In short, peptides trick the skin into believing there’s been a wound or an injury, which restarts our body’s healing processes.
Especially since they’re floating freely, and abundantly, inside our bodies? Well, that’s a good question. But the reality is that as we age, our bodies produce less and less collagen end elastin after the age of 30. Don’t believe me? Just look around and pay closer attention to the differences between the skin of young people, adults, and old people. See all those wrinkles, blemishes, ruggedness and looseness? All of that happens due to the slowing down of our metabolism, and with it, our peptides and protein production.
So, why do we need peptides? Because they’re barely enough as is, and because with time, we age, and the supplies our bodies naturally produce gradually dwindle. That is why using peptides in our skincare routine is very helpful, if not essential. And that’s why more and more skincare products use peptides as their main ingredient - because they can boost collagen and elastin. And boosting collagen and elastin helps the skin regenerate itself, regain its elasticity and combat aging.
Indeed, not all peptides are equal. And wondering whether all peptides are the same, or which one to use are very good questions. First off, there are many types of peptides, due to the dozens (or hundreds out in nature) amino acids that link together to form them. So, using one specific peptide will only lead to a specific set of effects.
That’s why you need to be choosy about which peptides you’re going to be using on your skin. To be sure, the skincare industry has already done its homework and their products use peptides whose properties will help your skin the most. However, that doesn’t mean that some peptides are as efficient as others, or that there are no differences.
Generally, doctors and dermatologists recommend the so-called carrier peptides for the skin. Carrier peptides attach themselves to trace minerals, and along with signaling the skin to boost collagen production, they also deliver useful minerals to the skin. Additionally, enzyme inhibiting peptides are useful as well, since they send signals to your skin to stop the dissolving of collagen. Another class of peptides, called signal peptides, send signals to your skin to restart collagen and elastin production in turn.
Finally, there’s a class of peptides compared to “botox,” called neurotransmitter peptides. These peptides send signals to your nerve endings, causing certain facial muscles to contract which leads to smoothing out wrinkles.
When it comes to specific peptides that have shown results in clinical trials and scientific research, the following two have shown the best results: Matrixyl (which is made up of Palmitoyl tetrapeptide-7 + Palmitoyl oligopeptide) and Palmitoyl pentapeptide-3.
While some people actually inject peptides in their bodies, that’s a whole different type of application that falls well outside of the scope of this article. For using peptides for the skin, it’s a fairly simple affair - you just need to apply them topically. Most skincare and beauty products that contain peptides are intended for topical use, so all you need to do is just follow the instructions on the package. Usually, applying the peptide products twice a day on the desired area of skin is enough.
However, you should remember that peptides need plenty of time to work their magic. Even with a disciplined and routine application of peptides, they still need at least six weeks until you can notice the differences. But are peptides safe to use?
Being completely natural, peptides are mostly harmless. However, some people may still experience adverse reactions of irritation and sometimes even allergies. While rare, typical adverse reactions to using peptides include itching, redness, inflammation or a rash. In order to avoid hurting yourself, it’s always a wise decision to perform a patch test before using a product that contains peptides. If you experience no side effects even after 24 hours, using that peptide product should be completely safe for you. However, if you experience any itching, redness, inflammation and so on, you should always consult with your doctor and dermatologist.
This information is meant to supplement, not replace advice from your doctor or healthcare provider and is not meant to cover all possible uses, precautions, interactions or adverse effects. This information may not fit your specific health circumstances, and its goal is to offer a general view of the subject. In case you are suffering from a severe case of acne, you should consult with a dermatologist or a certified medical professional.