How Drug Targets and PK-PD Inform Safety

Peptides are being marketed as solutions for everything from injury recovery to longevity, but what does the science actually say?

In this episode, Dr Leigh Baxt joins me to break down what peptides are, how drug development really works, and why so many of the claims circulating online are running far ahead of the evidence. We explore the difference between approved peptide medicines and unregulated products sold online, why anecdotes are not enough, and what people should understand before putting these compounds into their bodies.

What We Cover

• What peptides are and why they are not new
• FDA-approved peptide drugs versus unregulated peptides sold online
• Why scientists are concerned about the current peptide boom
• How drugs are developed and why most ideas fail
• Why animal and cell studies are not enough to establish safety and efficacy
• The problem with using “natural” as a proxy for safe
• How to think critically about peptide marketing and anecdotal claims

This is an important conversation for anyone trying to make sense of the peptide boom and separate genuine science from wellness hype.

To learn more from Dr Leigh Baxt, follow her on Instagram at @sciencemomscicomm. I also recommend exploring Unbiased Science, where science communication is made far more accessible for the public. You can follow the project on Instagram, Threads, Facebook, LinkedIn, X, subscribe on Substack, and watch on YouTube.

The views expressed are her own and she is not representing her employer.

• Intro (00:00)
• Stanford Expert Breaks Down the Peptide Hype (00:53)
• The Skill Set Behind Real Drug Development (05:09)
• FDA Approved vs Research Only Peptides Explained (08:03)
• Why Most Drug Candidates Never Become Medicine (11:06)
• Peptide Reclassification What Changes and What Doesn't (15:59)
• The Biological Risks Nobody Mentions About Peptides (20:36)
• Why Natural Peptides Are Not Necessarily Safe (23:00)
• What Safety Tests Drugs Must Pass First (28:51)
• Accepting Unknown Risk What That Actually Means (33:31)
• How to Find Credible Health Experts Online (36:13)
• Why Drug Development Always Requires A Team (39:19)

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Simon Hill, MSc, BSc (Hons)

• Creator of theproof.com
• Host of The Proof with Simon Hill
• Author of The Proof is in the Plants

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