Bariatric Rewrite UK

Why Willpower Won’t Win: The Science Behind Obesity and What Really Works

Helen&Evie Season 1 Episode 9

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Willpower has been oversold as the magic fix for weight loss — but the science says otherwise. In this episode, Helen and Evie dive into the latest research showing how biology, genetics, sleep, environment, and even the type of food processing can influence your weight far more than sheer determination. 

We break down why bariatric surgery is a powerful tool but not a cure, explore cutting-edge studies like the 2025 trial revealing that minimally processed foods can double fat loss compared to ultra-processed meals, and share practical, science-backed strategies that help you work with your body, not against it. 

Whether you’ve had surgery or are simply tired of the “try harder” narrative, this episode will help you see weight management in a whole new light — and give you the tools to finally outsmart willpower!

Links to the latest research:

PNAS, 2025 – Constrained energy expenditure model showing diet has more impact than exercise on weight loss. http://www.verywellhealth.com/slug-placeholder-11782834

Nature Medicine, 2025 – Swapping ultra-processed for minimally processed foods doubles fat loss with matched calories. http://nypost.com/2025/08/08/health/double-your-weight-loss-by-ditching-this-cancer-causing-food

JAMA, 2024 – Long-term outcomes after bariatric surgery (~30% weight loss at 1 year, sustained ~25% at 10 years). http://en.wikipedia.org/wiki/Bariatric_surgery#Long-term_effects

SELECT trial, NEJM 2024 – 17,604 adults; semaglutide led to 10% weight loss over 4 years, 20% fewer cardiovascular events. http://www.nejm.org/doi/full/10.1056/NEJMoa2304721

Cambridge University, 2023 – Obesity linked to enlarged, inflamed hypothalamus affecting hunger regulation. http://www.cam.ac.uk/research/news/brain-changes-in-obesity

Sleep restriction meta-analysis, 2024 – Sleep loss increases daily intake by ~250 kcal. http://www.sleepfoundation.org/nutrition/sleep-and-weight-loss

Genetic risk studies, 2025 – Up to 80% of weight predisposition inherited; ~12% of severe early-onset obesity due to single-gene mutations. http://timesofindia.indiatimes.com/city/hyderabad/intl-genetic-study-predicts-childhood-obesity-risk-using-indian-data/articleshow/122865432.cms

r/loseit online community analysis, 2024 – Supportive feedback linked to greater weight loss (~9 lbs more).http://arxiv.org/abs/2403.18911

Clinical trial meta-analysis, 2025 – Semaglutide and tirzepatide show 15–20% average weight loss. http://www.nejm.org/doi/full/10.1056/NEJMoa2304721

Metabolic adaptation research, 2024 – Reduced metabolism and increased hunger hormones after weight loss. http://www.science.org/doi/10.1126/science.aad4349

Dicken SJ, et al. Ultraprocessed or minimally processed diets following healthy dietary guidelines on weight and cardiometabolic health: a randomized, crossover trial. Nature Medicine. 2025 Aug 4. doi:10.1038/s41591-025-03842-0. http://www.nature.com/articles/s41591-025-03842-0

ScienceDaily coverage: “This diet helped people lose twice as much weight, without eating less.” (Aug 5, 2025)  http://www.sciencedaily.com/rel

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Disclaimer:
The content of this podcast is for entertainment purposes only and is not intended as a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of your doctor or other qualified health professional with any questions you may have regarding your health, medical conditions, or treatment options. The experiences shared are personal and may not reflect every individual’s journey. Never disregard professional medical advice or delay in seeking it because of something you’ve heard on this podcast.