Weight loss doubles when eating minimally processed foods over ultra-processed alternatives

By Admin

05 Aug, 2025

In the ever-evolving world of nutrition science, a groundbreaking clinical trial by researchers at University College London (UCL) and University College London Hospitals (UCLH) has shed new light on the importance of food processing in achieving and maintaining a healthy body weight. The study, recently published in Nature Medicine, offers a compelling case: eating minimally processed foods can lead to twice as much weight loss compared to eating ultra-processed foods even when both diets are nutritionally identical.

Real-World Proof: The First of Its Kind

This was the longest and most realistic experimental study to date comparing minimally processed foods (MPF) like homemade spaghetti Bolognese or overnight oats to ultra-processed foods (UPF) such as packaged lasagna or oat bars. The trial involved 55 adults divided into two groups who alternated between an eight-week MPF diet and an eight-week UPF diet, separated by a four-week "washout" period of normal eating.

Participants were not calorie-restricted. They received home-delivered meals, aligned with the UK’s Eatwell Guide containing balanced levels of fats, sugars, proteins, salt, and fibre and were told to eat as they pleased.

The Results: Twice the Weight Loss with MPF

Both groups lost weight on both diets, but the MPF diet led to a 2.06% weight loss, nearly double the 1.05% reduction seen with the UPF diet. This translates to a daily calorie deficit of 290 kcal on the MPF diet versus 120 kcal on the UPF diet.

More importantly, the MPF diet resulted in healthier body composition, with fat mass and total body water reduction, and no loss of muscle mass.

Cravings in Control: MPF Wins Again

Participants also reported significantly better control over food cravings on the MPF diet:

• 2x improvement in overall craving control
  
  

• 4x improvement in resisting savoury foods
  
  

• Nearly 2x improvement in resisting their most craved foods
  
  

Remarkably, even with greater weight loss (which can sometimes intensify cravings), those on the MPF diet felt more in control.

The Bigger Picture: Changing the Food Environment

While ultra-processed foods aren’t always nutritionally inferior, this study underscores that how our food is processed matters as much as what’s in it. With ultra-processed options dominating supermarket shelves due to their low cost and convenience, the study emphasizes that obesity is not merely a matter of personal choice. The global food environment shaped by multinational food corporations plays a massive role.

Policy interventions like front-of-pack warning labels, marketing restrictions, and food subsidies are needed to make healthy, minimally processed options accessible and appealing to all.

What About Other Health Markers?

Interestingly, despite UPF's bad reputation, the study found no significant negative changes in blood pressure, liver function, glucose levels, or cholesterol over the short term. Some even improved slightly, possibly because participants’ baseline diets were poorer than the trial's balanced UPF diet.

Still, researchers caution that longer studies are necessary to understand how these diets affect long-term health markers beyond weight.

Final Thoughts: A Return to Simplicity

Professor Rachel Batterham summed it up perfectly: “Choosing less processed options such as whole foods and cooking from scratch… is likely to offer additional benefits in terms of body weight, body composition, and overall health.”

This study makes a strong case for moving beyond calories and nutrition labels alone. If you're aiming for sustainable weight loss and better health, the fewer hands your food has passed through, the better.

Key Takeaway: A diet rich in minimally processed foods not only promotes greater weight loss but also enhances control over cravings and encourages healthier eating habits all without strict calorie counting or deprivation.

Let food be simple again. 🍎🥦🍲