It’s hard to miss the growing noise around ultra-processed foods (UPFs), a topic I am deeply passionate about. I regularly speak to corporates and schools on this subject, so I was really interested in a recent study co-authored by Dr Chris van Tulleken, which found that home-cooked meals and minimally processed foods (MPFs) are more effective for weight loss than their ultra-processed counterparts.
The link between UPFs and weight gain has been shown repeatedly in research. But what made this study unique was its design because it compared UPF and MPF diets while keeping both within the UK government’s Eatwell Guide recommendations. This is significant, because traditional nutritional advice has tended to focus on four main metrics: saturated fat, free sugar, salt and calories. These form the basis of our food labelling and the voluntary traffic light system, yet there is no mention of processing anywhere in our guidelines or on packaging.
The study followed 55 adults living with overweight or obesity, all of whom habitually consumed diets made up of at least 50% UPFs. Participants spent eight weeks on either a minimally processed diet or a UPF diet, followed by a four-week “washout” period eating their usual food, then swapped to the other diet for another eight weeks. Afterwards, they received six months of behavioural support to reduce UPF intake.
Calories were not restricted, just as in everyday life, but both diets met government limits for salt, sugar and saturated fat, and included at least five portions of fruit and vegetables a day. This meant the UPFs in the study were at the “healthier” end of the spectrum, rather than the high-salt, high-sugar, high-fat products we typically picture.
The results were telling: both groups lost weight, but those on the MPF diet lost around 2% of body weight compared to 1% for those on the UPF diet. When participants began the trial on the MPF diet, weight loss was even greater at 4%.
One likely reason is texture and calorie density. UPFs tend to be softer due to processing, making them easier to eat quickly. Combined with higher calorie density, this may delay the gut–brain satiety signal, allowing us to overeat before we realise we’re full.
I recently watched Dr van Tulleken and fellow co-author Dr Samuel Dicken discuss not just the study, but the broader health implications of UPFs.
In an ideal world, we’d all eat minimally processed food, but the reality is different. The cost-of-living crisis has driven up food prices, with healthier items often hit hardest. Many families and individuals simply cannot afford to avoid UPFs, and even when they can, time, cooking skills and confidence in the kitchen can be barriers.
Interestingly, quality-of-life scores in the study either stayed the same or improved for both groups. One possible explanation is that when food is provided, prepared, delivered and paid for, it can remove some of the daily stress around eating.
The challenge is that UPFs make up over half of the average UK adult’s diet, more than 70% for primary school children and over 80% for adolescents. They are embedded in our culture, from sugary breakfast cereals and lunchtime meal deals, to ready meals for dinner and even the food served in schools and hospitals. This is not the occasional treat, it makes up our food environment and our everyday reality.
Proposals to tackle the problem include taxation, marketing restrictions and warning labels on certain foods similar to those used in Mexico and Chile. But experts agree that no single measure will work alone. The food environment we live in is shaped by an industry driven by profit, producing foods engineered to be over-consumed. Just as with tobacco, asbestos and seat-belt laws, meaningful change is likely to require strong legislation, and the political will to put public health ahead of corporate interests.
At present, not everyone has the freedom to choose the healthiest foods because of the vast differences in cost and accessibility. That said, there are still steps we can take as individuals, households and communities to start shifting the balance.
As a nutritional therapist, I believe change begins with awareness. Once we understand what UPFs are and how they affect our health, we can start making small, achievable swaps- such as adding one more home-cooked meal a week, choosing less processed versions of foods we already enjoy or batch-cooking to save both time and money. It’s not about perfection, it’s about nudging our diets towards more whole, minimally processed foods over time.
The journey away from UPFs is not always straightforward, but with knowledge, planning, and community support, it is possible to reclaim a way of eating that nourishes both body and mind. Each step we take, however small, moves us closer to a food culture that truly supports our health.
If you’re interested in finding out more about my talks, workshops, webinars and courses on UPF and a range of other topics, please get in touch.
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