Ultra-processed foods have moved from a fringe concern to the centre of the nutrition conversation. They show up in headlines, social feeds, supermarket aisles, and household debates, and yet many people are still unsure what to actually do at the till. In this episode, I sit down with registered nutritionist and Sunday Times bestselling author Rhiannon Lambert to bring some clarity. Her latest book, The Unprocessed Platearrives at a moment when UK children are getting up to 70 per cent of their calories from UPFs and only around 4 per cent of UK adults are hitting the daily fibre target.
What I really wanted from this conversation was nuance. There is a version of the UPF discussion that paints every supermarket as toxic, and there is another that hides behind scientific complexity to defend the status quo. Rhiannon sits in neither camp. She runs a busy multidisciplinary clinic in London, has written extensively on the topic, and is currently consulting for one of the UK’s largest bread brands while pushing back on industry practices that have crept in unchallenged for decades. The result is a practical, real-world conversation about what UPFs actually are, which ones to genuinely worry about, and how to eat well in a food environment that has not been designed with your health in mind.
What We Cover:
- What ultra-processed foods really are, why the NOVA framework groups a baked bean and an ice cream into the same category, and how newer scoring systems like ZOE’s are bringing more nuance to the conversation
- Why calorie counts on packets can be 30 to 40 per cent inaccurate once you account for the food matrix, and what that means for whole almonds versus ground almonds, oats versus flour, and intact versus broken-down foods
- The 2025 Lancet paper linking UPFs to multiple cancers, the rise of bowel cancer in younger adults, and the UCL ready-meal study showing home-cooked groups losing twice as much body fat on identical calories
- Why “if your grandma can’t pronounce it, don’t eat it” is a heuristic Rhiannon firmly rejects, and how to tell the difference between fortification you should welcome and additives you should question
- The six UK food colourings linked to hyperactivity in children, the glycerol problem in slushies, the case for and against MSG, and where artificial sweeteners actually sit on the evidence
- Why “high protein” claims on packets are pulling attention away from fibre, salt, and sugar, and how to read a label in under thirty seconds using just a few markers
- The economics of eating well in the UK, the findings of the Broken Plate Report, and why a low-income household would have to spend close to 70 per cent of its budget to meet the Eat Well Plate
- Practical, low-friction strategies that work in real homes: nailing breakfast first, cook-once-eat-twice batch sauces, frozen bread for resistant starch, and the “little changes, big results” philosophy Rhiannon brings to her own family
This conversation is about reclaiming the kitchen without falling into purism. The science on UPFs is moving quickly, the marketing is moving faster, and the people who lose the most when we fail to engage carefully are the families with the least time and the smallest budget. Rhiannon is one of the clearest voices working at that intersection, and I hope this episode gives you a few small changes you can take into your week.
To learn more from Rhiannon Lambert, visit her clinic at rhitrition.com, follow her on Instagram at instagram.com/rhitrition and TikTok at tiktok.com/@rhitrition, and pick up her books, The Unprocessed Plate **and The Fibre Formula. You can also find her co-hosting The Wellness Scoop podcast with Ella Mills.
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More about Rhiannon Lambert
Rhiannon Lambert is one of the UK’s leading Registered Nutritionists and a Sunday Times bestselling author. She holds a first-class BSc in Nutrition and Health and an MSc in Obesity Risks and Prevention, and is also a Master Practitioner in Psychological Interventions for Eating Disorders. She is the founder of the Rhitrition Clinic and co-host of the chart-topping podcast The Wellness Scoop, which has surpassed 6 million downloads. Rhiannon is the author of The Science of Nutrition and Plant-Based Nutrition, as well as her more recent publications, The Unprocessed Plate and, this year, The Fibre Formula. Her latest book, The Fibre Formula, explores the science-backed benefits of fibre and highlights the growing recognition of gut health in supporting a wide range of common symptoms and long-term health outcomes.
