What to know about peptides and how they work

Injectable weight-loss medications, GLP-1s, have quickly become part of life for many people, bringing new attention to a class of compounds known as peptides. As interest grows, so does the importance of separating established science from social media hype. Peptides play a role in regulating processes from metabolism and sleep to joint recovery and skin health — but what exactly are they?

“Peptides are short chains of amino acids that function primarily as signaling molecules in the body,” says Dr. Joe Upton, a board-certified antiaging physician at Lévy Aesthetics. “They essentially tell cells how to respond and help regulate key biological processes.”

Some peptides are already well established in medicine. Insulin, for example, has been used for decades to regulate blood sugar, and newer peptide-based drugs like GLP-1 agonists are now widely prescribed for diabetes and weight management. The human body naturally produces thousands of peptides that help regulate metabolism, healing and inflammation and peptide therapy uses synthetic versions to support or mimic these natural processes.

Most people are now familiar with GLP-1 agonists (such as Ozempic and Wegovy) and their FDA-approved use for weight loss and diabetes management. While these are among the most visible examples, they represent just one category of peptide-based therapies.

“Peptides are a rapidly growing area of medicine,” says Upton. “They allow us to better target specific biological pathways with more precision than traditional pharmaceuticals — particularly for addressing targeted health concerns. We’re beginning to see how they may complement broader approaches to health and wellness.”

For example, clinicians are seeing early research exploring GLP-1s to treat inflammatory and autoimmune conditions. Another peptide gaining attention, especially on social media, is BPC-157. While not FDA-approved and still under investigation, animal studies suggest potential benefits for joint repair and injury recovery.

“A newer agent, retatrutide, is also generating interest in clinical research for its multi-hormone targeting effects on metabolism and weight loss, though it remains investigational and not yet FDA-approved,” he says. “In some clinical settings, providers may also use ‘peptide stacks,’ or combinations of peptides selected to target multiple pathways at once, though these approaches require careful medical oversight and are still an evolving area of practice.”

While media coverage has increased public awareness, the volume of information from unverified sources creates real challenges. Some peptides are well studied and clinically validated, while others are still emerging and not yet fully understood. Peptides show real promise in many areas, but they are not a quick fix that works in isolation. Their use is most effective when guided by qualified medical professionals and grounded in evidence-based care.

“Peptides really represent a bridge between traditional pharmaceuticals and a more regenerative medicine approach,” says Upton. “But they need to be used thoughtfully based on science and not on hype.”

In practice, that means evaluating peptide use within the broader context of a person’s overall health, lifestyle and medical history. The starting point is foundational lab data like metabolic panels and bloodwork, overseen by a physician. From there, the patient and provider can discuss specific biomarkers and how peptides might best complement a healthy lifestyle.

“I do a lot of hormone evaluation, optimizing hormones and improving overall health before we look at what kind of targeted peptide patients may want to add to the regimen,” Upton says. “Peptides in general should really amplify a good lifestyle. It’s an important tool, but it’s not always the first line of defense. It’s important to work with a provider that can really counsel people on their options.”

It’s also important to understand that FDA-approved peptides administered in a clinical setting are very different from the many peptide-labeled beauty and hair care products lining store shelves. One is a regulated medical treatment with documented benefits. The other is often more of a marketing claim with little scientific backing.

“Peptides have become a bit of a buzzword,” says Dr. Daniel Lévy, cosmetic dermatologist at Lévy Aesthetics. “The reality is that anything that has a chain of amino acids in the ingredient list can fashion itself as a peptide. It can sound scientifically pleasing and valid, but only certain peptides have been scientifically and rigorously studied and found to have efficacy and systemic functions in the body.”

As research continues to evolve, peptides are likely to play an expanding role in how clinicians approach areas such as metabolic health, recovery and aging. For consumers, understanding the difference between established therapies and emerging science — and seeking informed medical guidance — remains key to navigating this rapidly developing field.

Lévy Aesthetics is a Bellevue-based medical aesthetics studio specializing in injectables, laser skin rejuvenation, wellness treatments and advanced skincare. Learn more about our approach to natural, personalized results at Lévy Aesthetics.

Levy Aesthetics.