Peptides Explained

Peptides are short chains of amino acids that serve as the building blocks of proteins. They act as signaling molecules, helping regulate important biological processes such as metabolism, immune function, collagen production, tissue repair, and hormone activity. Peptides occur naturally in the body and are also found in foods such as fish, dairy products, and plants. In addition, many peptides can be synthetically produced and are used in modern medicine. Several peptide-based medications are well-established, FDA-approved treatments, including insulin, semaglutide (Ozempic/Wegovy), Tirzepatide (Mounjaro/Zepbound), liraglutide (Saxenda/Victoza), oxytocin, and tesamorelin.

More recently, however, non-prescription or over-the-counter (OTC) peptides have gained popularity as wellness and performance-enhancing supplements.** Unlike prescription peptide medications, these products are not FDA-approved and often lack meaningful human clinical trials that demonstrate safety and effectiveness. Because many of these substances remain largely untested, the short and long term hormonal and systemic effects are not fully understood.

Concerns also exist regarding product purity, dosing accuracy, and manufacturing standards, as many are produced in unregulated laboratories. Despite these concerns, OTC peptides are heavily marketed online and in fitness communities to athletes, bodybuilders, longevity enthusiasts, and “biohackers” seeking improvements in fat loss, muscle gain, recovery, sleep, cognition, and appearance. Popular compounds such as BPC-157, TB-500, CJC-1295, and Ipamorelin are frequently sold as “research peptides” through grey-market vendors.

A January 3, 2026 New York Times article by Jasmine Sun described the growing popularity of peptide use among Silicon Valley tech professionals, including so-called “peptide parties” where attendees discuss and experiment with grey-market peptides imported from China. According to the article, users are experimenting with compounds such as BPC-157 and TB-500 for injury healing, oxytocin for social interaction, epitalon for sleep, and retatrutide — a next-generation weight-loss drug still in clinical trials — for appetite suppression and cognitive enhancement(1).

Common Grey-Market Peptides and Their Claimed Uses

BPC-157 (“Body Protection Compound”)
A synthetic 15-amino acid peptide derived from compounds found in human gastric juice. It has been studied primarily in animal models for potential effects on tendon, muscle, ligament, and gastrointestinal healing. BPC-157 is not FDA-approved for human use and is banned by the World Anti-Doping Agency (WADA)(2).

TB-500
A synthetic peptide derived from Thymosin Beta-4, designed to promote tissue repair, reduce inflammation, and support healing of muscles, tendons, and ligaments. It is believed to work by promoting cell migration and blood vessel formation (angiogenesis). TB-500 has reportedly been used illegally in horse racing(3).

“Wolverine Blend”
A colloquial term for combining BPC-157 and TB-500 in an attempt to accelerate healing and recovery.

CJC-1295
A synthetic analogue of growth hormone-releasing hormone (GHRH) that stimulates the pituitary gland to increase natural growth hormone production. It is commonly marketed for fat loss, muscle growth, and recovery enhancement and is often paired with Ipamorelin(4).

Ipamorelin
A selective growth hormone secretagogue that stimulates natural growth hormone release by mimicking the hunger hormone ghrelin. Reported effects include improved body composition, sleep quality, recovery, lean muscle mass, and skin elasticity, although robust human evidence remains limited(5).

Melanotan II (MT2)
A synthetic peptide marketed for skin tanning. Its use has raised concerns due to potential side effects including new or changing moles and a possible increased melanoma risk.

It is also worth noting that many collagen-based peptides are widely used in the skincare and wellness industries. While generally marketed as low-risk supplements, many still lack strong FDA oversight and large-scale human clinical data supporting efficacy claims.

Peptides represent an important and legitimate area of modern medicine, with several FDA-approved peptide therapies playing critical roles in healthcare. At the same time, the rapid rise of grey-market and OTC peptides has outpaced scientific research and regulatory oversight. While many of these compounds are marketed with promises of enhanced healing, performance, and longevity, consumers should approach them cautiously due to limited human research, uncertain safety profiles, and inconsistent manufacturing standards. As interest in peptides continues to grow, further clinical research and regulation will be essential to better understand both their potential benefits and risks.

**This article is intended for educational purposes only and should not be interpreted as medical advice. Patients should consult a qualified healthcare provider before using any peptide-based therapy or supplement.

By Marcus Forman