You may have heard claims that C:15 (pentadecanoic acid) is the first essential fat discovered in 90 years, a powerful longevity booster, and a game-changer for metabolic health. But how much of this is backed by solid science?

In this episode, I sit down with Dr. Bill Harris, a leading expert in fatty acid research, to critically evaluate the evidence behind C:15. We break down the population studies linking it to health benefits, the key clinical trials testing its effects, and whether the marketing around Fatty15 is ahead of the actual data.

In this episode, we cover:

• What exactly is C:15, and how does it compare to other fats?
• The claim that C:15 is an essential nutrient—does it meet the criteria?
• The current evidence on C:15 and its impact on cholesterol, glucose, and inflammation
• Does C:15 supplementation mimic omega-3s, metformin, or rapamycin?
• The broader issue of patenting a naturally occurring compound

For more details and supporting studies, visit the full show notes.

• Introduction to Pentadecanoic Acid (C15) (00:00)
• Evaluating the Claims of C15 (02:05
• Comparing C15 with Other Fatty Acids (03:12)
• Health Implications of Dairy Fats and the Essentiality of C15 (05:02)
• Scientific Evidence and Studies on C15 (13:12)
• Interpreting Clinical Trial Results, Cholesterol, and the Tango Trial (27:59)
• Cholesterol and the Tango Trial (28:28)
• Comparing C15 to Omega 3s (32:02)
• Future Research Directions for C15 (37:46)
• Longevity Claims and Patents (42:30)
• Final Thoughts and Conclusion (49:44)

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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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