Peptides can have a variety of functions, such as acting as hormones, neurotransmitters, antibiotics, or even playing a role in regulating cell growth and development.
It is in the field of medical research and health where in recent years they have developed greater interest for their possible therapeutic applications and health benefits. In cosmetics, they are used to combat the cutaneous effects of aging.
You have probably heard of peptides as an ingredient in cosmetic and aesthetic formulations. Sometimes the term is used in advertising as a lure to try to achieve a higher number of sales.
They can be found in a variety of organisms, including plants, animals and microorganisms. In addition, chemical synthesis and genetic engineering have enabled the creation of synthetic peptides with specific properties for medical, cosmetic and scientific applications.
But peptides are not a panacea, nor do they “work magic”, they are simply chemical compounds that can aid in biological activities. Next, we will try to clarify the most common doubts about peptides, what they are used for, what types there are and why they are used.
What are peptides?
Peptides are molecules formed by the union of two or more amino acids by means of peptide bonds. Amino acids are the basic building blocks of proteins, and when combined into shorter chains than proteins, peptides are formed. These peptides can have diverse biological functions and play important roles in the human body and other organisms.
They are divided into different categories according to the length of the amino acid chain. Small peptides (oligopeptides) have less than 50 amino acids, while larger peptides (polypeptides) can be classified as proteins.
When they exceed the latter figure, we are talking about proteins. Within oligopeptides there are different variants:
- Dipeptides: they are made up of only two amino acids. The combination of these two amino acids creates a peptide bond, resulting in a basic dipeptide structure. Its function is to stimulate type IV, VII and XVII collagen.
- Triglycerides: composed of three amino acids, like dipeptides, triglycerides exhibit a simple linear structure formed by the union of three amino acids by means of peptide bonds. Their function is to enhance the production of collagen fibers, which is why they are called repairing peptides.
- Tetrapeptides: they consist of a specific sequence of four amino acids. Their application is intended to improve skin elasticity, while preventing collagen loss and stimulating its production.
- Pentapeptides: incorporate a chain of five interlinked amino acids. Contributes especially to the reduction of wrinkles. This amino acid sequence plays a crucial role in the process of collagen and elastin formation in the skin.
- Hexapeptides: These molecules relax the muscles and inhibit movement, causing the skin to tighten and wrinkles to be significantly reduced.
As more amino acids are added, oligopeptides can be classified into categories such as hexapeptides (six amino acids), heptapeptides (seven amino acids), and so on. Although they may be considered larger than shorter oligopeptides, they are still smaller compared to larger proteins.
Both types play essential roles in a variety of biological processes and have potential applications in fields such as medicine and biomedical research.
What are peptides used for?
Peptides have a wide variety of functions. The most important ones are related to hormone regulation in activities such as cell growth and development, metabolism, homeostasis and mood and pain perception.
They also participate as messengers in cell communication, have antioxidant and anti-inflammatory properties and possess antimicrobial effects.
What are peptides used for in cosmetics?
Some peptides are able to stimulate collagen production, which provides firmness and elasticity to the skin. Other peptides, as mentioned in the previous section, have antioxidant properties, which can combat oxidative stress and premature aging caused by environmental factors.
Thanks to the size of the peptides, they have the ability to penetrate the skin barrier and reach deeper layers of the skin. This enhances its beneficial health effects, which are, in addition to those already mentioned, hydration and anti-inflammatory capacity.
The efficacy of peptides in a cosmetic product is usually linked to their concentration. Therefore, look for products that clearly indicate the concentration of their formula. A higher concentration may suggest greater efficacy, but it is crucial to balance this with skin tolerance. You can learn more about how to read a cosmetic formula in this article on INCI.
