Review Finds Limited Evidence for Popular Peptide Supplements

A review of 565 studies found little clinical evidence supporting six peptide supplements marketed for sports performance, tissue recovery and longevity. The analysis, published in The American Journal of Sports Medicine, also identified concerns about study quality, potential risks and the contents of products sold outside established regulatory oversight.

The review examined BPC-157, TB-500, CJC-1295, MK-677, ipamorelin and GHK-Cu in animal and human models. According to Medical Xpress, more than two-thirds of the studies involved animals. Those experiments reported promising but inconsistent effects on tendon, muscle, bone and ligament healing, but the review emphasized that findings in rodents may not translate to people.

Human evidence was considerably thinner. A small number of human studies reported modest improvements for nonorthopedic uses, while the review found essentially no studies demonstrating significant clinical benefits for musculoskeletal conditions. Studies that appeared to show positive results often lacked strong control groups or rigorous designs. The article also described cases in which evidence for a topical product used for a skin condition was used to support claims about injectable treatment for musculoskeletal problems.

Conflicts of interest were another concern. Kushagra Tewari, a co-author of the review, said the researchers identified financial ties involving the compound in one of the largest BPC-157 studies. The authors said stronger research would be needed to assess whether these substances provide meaningful benefits.

The review also described safety signals. In one documented trial of MK-677, the trial was stopped after one group experienced a higher rate of congestive heart failure. Thomas Kremen, a sports medicine specialist and review co-author, also described a patient preparing for rotator cuff surgery who reported using peptides and was found to have severely reduced cardiac output. Kremen said the case could not establish causality but raised a concern.

Product quality presents a separate issue. The peptides discussed in the review are not regulated or vetted by the U.S. Food and Drug Administration, according to the Medical Xpress report. Kremen said consumers may not know whether a product contains the labeled compound or other substances. The article cited tests finding dangerous contaminants, including arsenic or lead, in some products.

The report also described products imported from China that may carry labels stating they are not for human use. Some are later mixed by compounding pharmacies and marketed online as “gray-market peptides” or for “research purposes only,” leaving uncertainty about what is ultimately present in a vial. Buying from multiple websites when a desired effect does not occur may increase the risk of exposure to tainted products, Tewari said.

The review does not establish that every peptide product is harmful, nor does it determine that any individual’s symptoms were caused by peptide use. Its findings instead point to a gap between promotional claims and the available evidence, particularly for musculoskeletal recovery and performance enhancement.

The authors reported that patients and recreational athletes are increasingly asking about peptides promoted for faster recovery, greater strength or longer-lasting performance. Kremen said the established foundations discussed by the clinicians include sleep, nutrition, strength training and aerobic training, while recovery plans should be based on assessment by medical professionals.

The review, titled “Peptide Supplements and Their Therapeutic Applications in Sports Medicine,” was authored by Kushagra Tewari and colleagues and published in 2026.