What Are Peptides and What Are They Used For?

Peptides are chains of amino acids—the building blocks of proteins—that are naturally found in your body. 

In addition to performing a number of important functions in your body, they can also be found in foods, supplements, medications, and skincare products. 

Here’s everything you need to know about peptides, including what they are, where they’re found, and how they benefit health. 

What Are Peptides?

Peptides are chains of amino acids. Like the beads on a bracelet, amino acids link together to form peptides. Peptides typically contain between two and 50 amino acids in a chain. Peptides are split into two groups: endogenous peptides and exogenous peptides.

Endogenous peptides are produced in different cells in your body, from neural cells to the cells of the immune system. Each protein in your body is made up of a single chain consisting of 20 or more amino acids, which is known as a polypeptide. The polypeptides are linked together by a chemical bond called a peptide bond.

Each of these chains contains amino acids linked together in a specific order, which determines the peptide’s function and structure. Peptides are necessary for a number of critical processes in the body, from wound healing to cellular communication.

Exogenous peptides are peptides that enter your body from outside sources, like food, supplements, and medications.

Peptides in Supplements and Food

Exogenous peptides are often found in dietary supplements. This is because peptides are more easily absorbed by the body than intact proteins. Proteins are larger than peptides and are more difficult for the body to break down and absorb. This is why you’ll find peptide-based supplements, like collagen peptides. 

What’s more, peptides are less likely to cause allergic reactions than whole proteins, which is why peptides are often used in infant formula. 

Peptides are naturally found in foods like dairy products, grains, meat, and seafood. Some peptides found in certain foods have anti-inflammatory, antioxidant, and blood pressure-lowering properties.

Peptides in Drugs and Cosmetics 

In addition to their use in dietary supplements and food, peptides are commonly used in medications. Therapeutic peptides are special peptides used in the pharmaceutical field. There’s currently 80 approved peptide drugs worldwide. Insulin is an example of a peptide drug, which is composed of 51 amino acids.

Peptides are also used in cosmetic products, like creams and serums. Peptides may help improve skin moisture, reduce skin inflammation, and protect against sun damage.

Benefits of Peptides

When taken as a supplement or used as a medication or in skincare, peptides offer a variety of health benefits.

Certain peptides found in foods like dairy products may have positive effects on health as well. 

Here are some of the health benefits of peptides. 

May Improve Muscle Health and Sports Performance

When taken as a supplement, studies show that certain peptides could help improve body composition, reduce exercise-induced muscle damage, and improve joint health and mobility in athletes and nonathletes. For example, a number of studies have found that collagen peptide supplements are effective for increasing muscle strength, reducing joint pain, and improving joint mobility in athletes and sedentary people.

Most collagen supplements are hydrolyzed — or broken down — into peptides for easier absorption. Collagen peptides may also help improve endurance performance in athletes by stimulating the uptake of glucose (sugar) and the storage of glycogen — the storage form of glucose — in muscle cells. What’s more, collagen peptide supplementation may help increase muscle mass in non-athletic people with low muscle mass like older men and women. 7 Certain peptides, like the collagen-derived peptide dipeptide hydroxyproline-glycine, activate pathways in the body that stimulate the growth of muscle fibers. 

Other peptides used to increase muscle mass include growth hormone (GH) releasing peptides. These peptides stimulate the production and release of human growth hormone (HGH), a hormone that can induce muscle growth, which is why these supplements are popular with bodybuilders.

May Benefit Brain Function and Mental Health

Opioid peptides are peptides found in certain foods and in your body that bind to certain receptors in the brain. Exogenous opioid peptides may have positive effects on the nervous system and may benefit stress, anxiety, and depression.

Animal and human studies have shown that peptides derived from food like soy and dairy may help improve brain function and help reduce anxiety.

Researchers are currently investigating how exogenous peptides could be used in the future for pain relief, stress reduction, and more.

Could Improve Skin Health

Collagen is a major component of your skin and helps provide structure, strength, and elasticity. As we age, we lose collagen. Supplementing with collagen peptides may help reduce wrinkle depth and improve skin hydration.

Studies show that supplements with collagen peptides can help improve skin elasticity, reduce skin dryness and wrinkles, and increase collagen levels in the skin. Collagen peptides are rapidly absorbed in the digestive tract and accumulate in the skin around 96 hours after ingestion.

Collagen peptides can remain in the skin for up to 14 days, where they help improve skin elasticity, protect against sun damage, reduce skin dryness and wrinkles, and increase collagen levels.

Topical skincare products that are made with peptides also offer skin health benefits, from improving signs of aging to reducing skin inflammation.

Other Potential Benefits

Peptides have a wide range of uses in many different fields, including as pharmaceuticals, supplements, and as ingredients in skincare products. 

In addition to those listed above, peptides offer other health benefits. For example, peptides are used as drugs in the pharmaceutical field to treat a number of medical conditions as well as in skincare products like moisturizers.

Potential Side Effects

Because there are many different peptides used in different ways, including as supplements, medications, and skincare products, they can be associated with some side effects. There are around 80 approved peptide medications used to treat medical conditions like diabetes, cancer, osteoporosis, and HIV. Like all medications, peptide medications may cause side effects.

Collagen peptides, one of the most common peptide-based supplements, aren’t associated with many adverse side effects but could cause nausea, diarrhea, and bloating in some people.

The long-term safety of GH-releasing peptides isn’t well studied. Even though GH-releasing peptides may be helpful for several conditions when prescribed by a healthcare provider, off-label use of GH-releasing peptides isn’t safe or recommended.

How to Find the Right Peptide Supplement For You

Collagen peptides are the most common type of peptide supplement you’ll find in grocery stores, health food stores, and online.

When shopping for a collagen peptide supplement, it’s important to purchase products from reputable companies. Some companies are certified by third-party organizations like UL, USP, and NSF International, which set strict standards for supplement quality and safety. 

Most collagen peptide supplements come in powdered form, but they’re also available as liquids, capsules, and gummies. 

Some collagen peptide products contain additives like added sugar, artificial colors, and flavors, which some people prefer to leave out of their diet. When shopping for collagen peptides, be sure to scan the ingredient label if you’d like to avoid certain ingredients.