FDA scientists flag concerns with peptides, the trendy molecules RFK Jr. supports

June 30, 20262:32 PM ET

By 

Will Stone

Synthetic peptides, often taken by injection, are growing in popularity among patients seeking to optimize health and longevity. Yet FDA scientists point to a dearth of evidence supporting their use.

Svitlana Pietukhova/iStockphoto/Getty Images

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While Health Secretary Robert F. Kennedy Jr. pushes to loosen restrictions on a handful of trendy peptide therapies, scientists who work under him are recommending the opposite.

On Monday, the Food and Drug Administration posted documents outlining concerns about a lack of evidence for the batch of peptides set to be considered by an FDA panel in about three weeks.

Peptides are a string of amino acids, smaller than a protein, that are produced naturally by our body. The wildly successful GLP-1 weight loss drugs are examples of synthetic peptides.