Peptides are rapidly gaining popularity in wellness and fitness circles, but medical experts say the science behind many of these products remains uncertain.
Once largely confined to scientific research, peptides are now widely promoted online and in clinics for uses ranging from injury recovery to anti-ageing and weight loss. However, doctors warn that many of these claims are not supported by strong clinical evidence.
Peptides are short chains of amino acids, the building blocks of proteins, and play important roles in the body, including acting as signalling molecules. Some peptide-based drugs, such as insulin and semaglutide, have been rigorously tested and approved for medical use.
The success of these medicines has helped fuel broader interest in peptides. But experts say this has also created confusion, with many people assuming that other marketed peptides have undergone similar testing. In reality, many widely promoted compounds—including BPC-157 and TB-500—are not approved by regulators.
The US Food and Drug Administration (FDA) has previously raised concerns about several of these substances, citing potential safety risks such as immune reactions, contamination, and uncertainty about their composition. Although some peptides have since moved into a regulatory “grey area,” they remain neither approved nor fully authorised for general use.
In July, an FDA advisory committee recommended that several peptides could be considered for compounding by pharmacies. However, experts stress that this does not amount to approval. Any regulatory change would still require further review and could take significant time.
Medical professionals also note that the conditions being studied for these peptides—such as ulcerative colitis or wound healing—often differ from the claims made in advertisements, which frequently focus on athletic performance, recovery, or longevity.
At the same time, demand has grown alongside trends in biohacking and self-optimisation. Wellness clinics, online influencers, and social media platforms have contributed to normalising the use of injectable treatments, even outside traditional medical settings.
Some individuals have gone further, purchasing so-called “research-use-only” peptides online and administering them without medical supervision. Experts warn that this carries significant risks, particularly when the source and quality of the substances cannot be verified.
Doctors advise consumers to approach peptide treatments with caution. Key questions include whether there is clear evidence supporting their use, what is known about safety, and whether approved alternatives already exist.
They emphasise that while peptides themselves are not new, the current surge in marketing may be giving a misleading impression of their safety and effectiveness.
“The peptides did not get safer,” one expert noted. “The marketing just got better.”