In 18 months, Steffan Rhys shed 21 pounds and transformed his health—not by cutting portions or obsessing over macros, but by eliminating one specific category of food from his diet. His approach contradicts everything we’ve been told about weight loss requiring strict calorie counting and food restriction.
The results speak for themselves: 21 pounds lost, three personal bests in half marathons with 25 minutes shaved off his time, and a gut microbiome score that rocketed to 93 out of 100. All achieved without stepping foot in a gym more than twice a week or measuring a single calorie.
What Rhys eliminated wasn’t carbs, fats, or even sugar entirely. Instead, he completely cut ultra-processed foods (UPFs) from his diet—a decision that began as a simple New Year’s resolution but evolved into what he calls a “transformative” lifestyle change.
The transformation wasn’t just physical. Rhys discovered flavors he’d never experienced, developed cooking skills he didn’t know he possessed, and gained insights into the food industry that fundamentally changed how he thinks about eating. Most remarkably, he describes the transition as “effortless”—a stark contrast to the struggle most people associate with sustainable weight loss.
What Exactly Are Ultra-Processed Foods?
Ultra-processed foods aren’t just any packaged item on the supermarket shelf. They’re foods that contain ingredients you wouldn’t typically find in a domestic kitchen—things like emulsifiers, preservatives, artificial sweeteners, and industrial additives that extend shelf life and enhance flavor.
Dr. Chris Van Tulleken, an infectious diseases doctor at University College London and BBC science presenter, offers a practical definition: “If it’s wrapped in plastic and it contains at least one ingredient that you don’t typically find in a domestic kitchen, then it’s ultra-processed food.”
This distinction is crucial because not all processed foods are created equal. Humans have been processing food for millennia—bread, butter, cheese, and yogurt all undergo processing. Even canned foods represent traditional processing methods that preserve nutrients and extend shelf life.
The problem lies in the industrial manipulation that characterizes ultra-processed foods. Professor Tim Spector, co-founder of Zoe and a leading epidemiologist, explains the difference: “Plain yoghurt, nothing added, nothing changed, is processed because you are mixing a basic ingredient, milk, with microbes… It is when you take it to the next stage… [adding] various starches, emulsifiers, concentrates, artificial sweeteners and flavourings… that same yoghurt becomes ultra-processed. It is that extra step that is the main problem.”
Common ultra-processed foods include:
- Packaged bread from supermarkets
- Breakfast cereals and granola
- Flavored yogurt
- Chocolate, biscuits, and crisps
- Energy and granola bars
- Fizzy drinks
- Ready-made sauces and salad dressings
However, nuance matters. High-quality dark chocolate with 80% cocoa content technically qualifies as ultra-processed but contains minimal ingredients. Even Spector acknowledges that items like Heinz tomato ketchup and Weetabix, while technically ultra-processed, pose minimal health risks.
The Counterintuitive Truth About Weight Loss
Here’s where conventional wisdom gets turned upside down: Rhys didn’t restrict his food intake, count calories, or obsess over fat and carbohydrate content. In fact, he consumes around 150 grams of fat daily—sometimes more.
This flies in the face of decades of dietary advice that has focused on calorie restriction and portion control as the primary drivers of weight loss. The diet industry has built a multi-billion dollar empire on the premise that weight loss requires suffering, deprivation, and constant vigilance.
But research suggests a different story. Studies show that people consuming ultra-processed foods eat approximately 500 more calories daily compared to those eating whole foods. In one compelling experiment, Dr. Chris Van Tulleken modified his diet to consist of 80% ultra-processed food—a pattern common in the UK and US—and observed alarming results: “I gained a huge amount of weight in one month. I gained so much weight that if I’d continued for the whole year, I would’ve doubled my body weight.”
The mechanism isn’t mysterious. Ultra-processed foods are engineered to be irresistible. Food corporations have invested millions in research to understand exactly how to manipulate texture, flavor, and even the sound packaging makes when opened to encourage overconsumption.
The key insight: When you eliminate foods designed to make you overeat, you naturally consume fewer calories without conscious restriction. Your appetite regulates itself when it’s not being hijacked by industrial food engineering.
How Rhys Transformed His Diet
The transition didn’t happen overnight, but Rhys’s approach was methodical rather than overwhelming. He made strategic swaps rather than eliminating entire food groups:
Breakfast Revolution: Instead of granola with flavored yogurt—which he’d mistakenly believed was healthy—he switched to Greek yogurt with nuts, seeds, and fresh fruit. This single change eliminated hidden sugars and artificial additives while providing sustained energy.
Snack Upgrades: Milk chocolate gave way to dark chocolate with 80% or higher cocoa content. The higher cocoa concentration means less sugar and more beneficial compounds like flavonoids.
Pantry Overhaul: Out went supermarket bread, crisps, biscuits, ice cream, ready-made foods, and processed meats. In came legumes—chickpeas, lentils, beans—and a variety of nuts.
The 30-Plant Challenge: Rhys adopted the goal of consuming at least 30 different plants each week, a target backed by research showing its benefits for gut microbiome diversity.
Sauce Solutions: Rather than buying processed condiments, he began making his own combinations using spices, herbs, fruits, nuts, and vegetables. His go-to salad dressing became a blend of Greek yogurt and tahini with lemon juice, olive oil, or a hint of maple syrup.
The Unexpected Benefits
Weight loss was just the beginning. The changes cascaded into areas of Rhys’s life he hadn’t anticipated:
Enhanced Athletic Performance
Despite not increasing his exercise regimen—still running occasionally and attending one or two circuit classes per week—Rhys achieved three personal bests in half marathons and two in 10K races. His half-marathon time improved by 25 minutes, a significant achievement for any recreational runner.
This improvement likely stems from better nutrient density in his diet. When your body receives optimal fuel rather than empty calories, energy levels stabilize, inflammation decreases, and recovery improves.
Culinary Discovery
Avoiding ready-made sauces and dressings forced creativity. Instead of reaching for processed flavor enhancers, Rhys learned to create complex tastes using whole ingredients. This wasn’t a burden—it became a source of joy and discovery.
He now regularly uses foods he rarely consumed before: chickpeas, butter beans, lentils, various nuts, and Greek yogurt. The variety in his diet increased dramatically even as he eliminated processed options.
Improved Gut Health
As a Zoe member, Rhys could track his gut microbiome score, which skyrocketed to 93 out of 100 after just 12 months. This improvement reflects the diversity of plants in his diet and the elimination of additives that can disrupt beneficial gut bacteria.
Research from 2018 spanning the USA, UK, and Australia found that individuals consuming 30 or more different plants per week were more likely to harbor beneficial gut bacteria compared to those eating only 10 different plants.
A Typical Day of Eating
Breakfast: Greek yogurt with a mix of nuts (almonds, Brazil nuts, walnuts, hazelnuts, or cashews), seeds (chia, pumpkin, or linseed), and fresh fruit (raspberries, strawberries, bananas, and blueberries). Alternative: avocado on wholemeal sourdough from a local bakery.
Lunch: Lentils with vegetables and homemade hummus made from chickpeas or butter beans. Or an omelette with onions and peppers.
Dinner: White fish like hake, cod, or basa (chosen for affordability), or salmon, paired with butter beans or chickpeas flavored with onions, mint, and lemon juice.
The fat content is substantial—around 150 grams daily—but comes from healthy sources like nuts, avocados, olive oil, and fish. This challenges the low-fat dogma that dominated nutrition advice for decades.
The 30-Plant Strategy
Thirty different plants per week might sound daunting, but it’s more achievable than it appears. The count includes more than just fruits and vegetables:
Legumes: Butter beans, cannellini beans, black beans, kidney beans, pinto beans, lentils, chickpeas Grains: Oats, quinoa, bulgur wheat, brown rice Nuts: Almonds, cashews, pine nuts, walnuts, pistachios, Brazil nuts Seeds: Chia, pumpkin, sesame, sunflower, flax Herbs and Spices: Basil, oregano, turmeric, cumin, cinnamon Beverages: Coffee and cocoa (which contain beneficial plant compounds)
The goal isn’t perfection but progress. Even increasing from 10 to 20 different plants per week provides significant benefits for gut microbiome diversity.
The Sweet Solution
Eliminating ultra-processed foods doesn’t mean eliminating sweetness. Rhys discovered that homemade alternatives could satisfy cravings while providing nutritional benefits:
- Chocolate mousse made from dark chocolate, olive oil, maple syrup, and aquafaba
- Homemade granola with natural ingredients and no added sugars
- Healthy chocolate and peanut butter bars using whole food ingredients
These alternatives provide the satisfaction of sweet treats without the engineered addictiveness of commercial products.
The Industry Reality Check
As Rhys dove deeper into eliminating ultra-processed foods, he uncovered the extent of food industry manipulation. The creation of these products involves sophisticated marketing and psychological manipulation, including bold health claims on attention-grabbing packaging.
Food companies have invested millions in research aimed at making consumers eat more—from the sound a package makes when opened to the texture of food in the mouth and that irresistible flavor that leaves people craving more.
The manipulation is comprehensive:
- Visual design that triggers impulse purchases
- Flavor profiles that activate reward pathways in the brain
- Textures that encourage rapid consumption
- Packaging that suggests health benefits despite poor nutritional profiles
This insight added ethical motivation to Rhys’s dietary choices. Beyond personal health, he found satisfaction in withdrawing financial support from companies that prioritize profits over public health.
The Practical Approach
Rhys’s transformation was comprehensive, but perfectionism isn’t required. Even organizations like Zoe, which strongly advocate for limiting ultra-processed foods, suggest keeping them under 15% of total diet rather than eliminating them entirely.
Professor Tim Spector shared with Rhys that his approach might seem “restrictive” and admits he occasionally enjoys a bag of chips. The key is progress, not perfection.
Practical considerations include:
- Dining out can present challenges
- Social situations may require flexibility
- Complete elimination isn’t necessary for significant benefits
- Small indulgences can be maintained (Rhys still consumes alcohol)
The Sustainability Factor
What makes Rhys’s approach remarkable is its sustainability. Unlike restrictive diets that require constant willpower, eliminating ultra-processed foods removes the source of cravings rather than fighting them.
When you’re not consuming foods engineered to be addictive, appetite naturally regulates. Energy levels stabilize, reducing the cycle of sugar crashes and carbohydrate cravings that drive overeating.
The changes become self-reinforcing:
- Better energy leads to more physical activity
- Improved sleep quality supports hormone balance
- Enhanced mood reduces emotional eating
- Cooking skills develop, making healthy choices easier
The Broader Implications
Rhys’s experience reflects a growing body of research highlighting the connection between ultra-processed foods and various health problems. Beyond weight gain, these foods have been linked to increased risk of heart disease, diabetes, certain cancers, and mental health issues.
The transformation goes beyond individual health. By choosing whole foods over processed alternatives, consumers send market signals that can influence food industry practices. Every purchase is a vote for the kind of food system we want to support.
The Bottom Line
Rhys’s 18-month journey demonstrates that sustainable weight loss and health improvement don’t require deprivation or complex rules. By focusing on food quality rather than quantity, he achieved results that had eluded him through traditional dieting approaches.
The key insights:
- Ultra-processed foods are engineered to promote overconsumption
- Eliminating them allows natural appetite regulation
- Weight loss becomes effortless when you’re not fighting food engineering
- Health benefits extend far beyond the scale
- The approach is sustainable because it doesn’t require constant willpower
The most compelling aspect of Rhys’s transformation isn’t just the 21 pounds lost or the improved athletic performance—it’s the ease with which he maintains these changes. When healthy eating becomes enjoyable rather than restrictive, lasting transformation becomes possible.
For anyone struggling with weight management or seeking better health, Rhys’s approach offers a different path forward—one that works with your body’s natural systems rather than against them. The question isn’t whether you can sustain another restrictive diet, but whether you’re ready to eliminate the foods that make healthy eating unnecessarily difficult.
