What Makes Us Fat? The Genetics of Appetite | Giles Yeo

💬 Dr. Giles Yeo is a geneticist and obesity researcher at the University of Cambridge. He specialises in how brain and genetic factors influence appetite and body weight regulation. He’s known for communicating complex science around obesity, appetite, and nutrition in an accessible way through media, books, and public talks.

⚡️In this episode, Giles and I dig into how our genes - especially those in the brain’s appetite and reward centres - shape our hunger signals, fat storage, and body fat “set‑points”. We explain why diets often fail and how to reset our appetite.

🎧 Stay tuned to find out:

➡︎ Just how strongly our genes are to blame for appetite and body weight

➡︎ The specific brain region that regulates hunger and energy balance

➡︎ Whether weight loss injections are really the answer

➡︎ Why obesity is biological - not a moral failing

➡︎ The 3 numbers to remember for weight loss

📕 Chapters

(00:47) Welcome back

(01:01) The genetic reason for obesity

(02:49) The role of the brain in weight gain

(05:15) Reward, hunger and fullness

(08:14) How fat cells influence how hungry you are

(10:09) The hypothalamus map

(13:19) What to do when your meal’s not enough

(16:16) Why hormones don’t limit your appetite

(18:21) The paradox of leptin resistance

(20:55) Insulin resistance and weight gain

(22:30) Defining high quality weight loss

(24:56) The yo-yo effect

(26:13) Why weight loss drugs aren’t enough

(30:17) The wider benefits of GLP-1 agonist weight loss drugs

(34:19) Gene mutation and obesity

(37:43) Gut hormones and the role they play

(41:06) The effect of early years education

(44:30) Three numbers to remember

(46:23) Your DNA isn’t your destiny

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📱 Connect with Dr Giles Yeo:

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📕 Grab Giles’ book here: https://amzn.eu/d/hoAnVLr

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🎙️ An OG Podcasts production.