Harriët Schellekens Podcast: Why Diets Don’t work & The Science of Appetite

24 Feb 2026

Dr. Harriët Schellekens, APC Microbiome Ireland, Senior Lecturer in Anatomy and Neuroscience at UCC and leading expert on the hunger hormone ghrelin, joins Barry Skillington of Atlantia Clinical Trials to unpack the complex biology of appetite and the science behind GLP-1 medications. They explore how these drugs affect appetite and food reward pathways, why they represent a major step forward in obesity treatment, and why they are not designed as a shortcut for weight loss in people without obesity.

From gut hormones to microbiome signaling, Harriët explains how your body decides when you're hungry, why ultra-processed foods hijack your brain's reward system, and how your gut bacteria might actually be driving your food cravings. If you've ever felt like your biology is working against you, this episode will help you understand why - and what you can actually do about it.

Harriët discusses what GLP-1 drugs actually do - and who they're really for. The hunger hormone ghrelin and how it drives food intake. Why obesity is a disease, not a lifestyle problem. The pre-digestive vs. post-digestive mismatch in ultra-processed foods. How high-fat, high-sugar foods create a "false promise" in your gut. Sugar substitutes: the good, the bad, and the gut-friendly. How your gut microbiome influences weight gain and food preferences. Why crash diets backfire (and what to do instead). The role of stress, cortisol, and emotional eating. Early-life food exposure and how it shapes lifelong eating habits. Probiotics, prebiotics, and targeting the microbiome for better appetite control. Practical tips for parents navigating kids' diets and food choices.

The bottom line? Your food choices aren't just about willpower - they're about biology. Understanding how your gut, brain, and microbiome communicate can help you make better decisions, break unhealthy cycles, and stop fighting your own body. Don't eat less. Eat better.

PODCAST LISTEN HERE:  Why Diets Don't Work: The Science of Appetite