Food Labels, Fibre, and Ultra-Processed Foods: What Really Matters | Rhiannon Lambert

April 28, 2026

AI Summary

5 min read

Ultra-processed foods now account for more than half of the average American, Australian, or Brit’s weekly shopping cart, and for children, it’s closer to 70% of daily calories. Yet the public conversation about this category has become a mess—one side calling every ultra-processed food a poison, the other calling it overblown. Registered nutritionist Rhiannon Lambert, author of The Unprocessed Plate, argues that neither extreme is helpful. Her approach avoids fear and absolutes, focusing instead on practical nuance: some ultra-processed foods are genuinely worth worrying about, others are perfectly fine, and sometimes they are even a better choice than what they replace.

Why ultra-processed foods matter—and why the category is messy

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What you'll learn

1 (01:49) **Rhiannon's Journey into Nutrition** - From classical singer to registered nutritionist, driven by a desire to understand how to fuel her body properly.
2 (07:35) **Why She Wrote "The Unprocessed Plate"** - Frustration with the lack of practical guidance in the ultra-processed food (UPF) conversation drove her to write a book that cuts through the noise.
3 (13:43) **The Nuance of Ultra-Processed Foods** - Not all UPFs are created equal; the NOVA system is useful but creates a broad "grey area" category.
4 (16:23) **The Food Matrix: Why UPFs Affect Us Differently** - The physical structure of food changes how we absorb calories and impacts our gut bacteria.
5 (22:34) **What a Healthy Diet Looks Like in a UPF World** - A healthy pattern is about displacement and proportion, not elimination, with a focus on increasing fiber.
6 (30:42) **The Fiber-First Strategy** - Focusing on fiber is a positive, actionable goal that naturally reduces UPF intake.
7 (32:40) **Practical Strategies for Busy People** - Start small, cook once eat twice, and build a repertoire of quick, staple meals.

+ Full timestamped outline available in the app

Show Notes

Ultra-processed foods are now the central nutrition conversation of the decade, but the gap between the marketing and the evidence has never been wider. In this episode, I sit down with registered nutritionist and Sunday Times bestselling author Rhiannon Lambert to bring some practical clarity to what the science actually says.

We get into how the NOVA system can be too blunt to be useful, why calorie counts on packets are often 30 to 40 per cent inaccurate, what the most recent UPF and cancer data actually shows, and how to spot the difference between sensible fortification and the additives that are genuinely worth questioning.

What we cover:

What ultra-processed foods really are, and why the NOVA category is so blunt
The food matrix and why calorie labels can be misleading
UPFs, cancer risk, and the UCL home-cooking study
The UK colourings linked to hyperactivity, MSG, and artificial sweeteners
How to read a label in under thirty seconds
Practical strategies for cooking more at home, even on a budget

This is a conversation about reclaiming the kitchen without falling into purism. If it lands, a quick rating or review on Apple Podcasts or Spotify makes a real difference.

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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