Welcome back to the club. Today's edition explores:
Deep Dive: Same healthy diet, twice the weight loss when the food was less processed
Pillar Spotlight: Why short sleep may make you more likely to catch a cold
Video of the Week: What one of the longest studies on happiness reveals about a good life
DEEP DIVE
Same Healthy Diet, Twice The Weight Loss
Can ultra-processed food still be healthy if it fits the official guidelines? A new UK trial put that to the test.
Researchers recruited 55 adults in England who were overweight and got at least half their calories from ultra-processed food. Each person followed two diets for eight weeks, in random order, with a four-week break in between.
Both diets followed the NHS Eatwell Guide, the UK's official advice on healthy eating. One was minimally processed, the kind of food you might cook at home. The other was ultra-processed but healthy on paper, built around foods like breakfast cereals, ready meals and plant-based alternatives. Every meal, snack and drink was delivered to people's homes twice a week, and they could eat as much as they liked.
Both diets led to weight loss, but not equally. On the minimally processed diet, people lost 2.06 percent of their body weight, roughly double the 1.05 percent on the ultra-processed diet. They also lost about 1kg more body fat. Triglycerides, a type of fat in the blood, fell on the minimally processed diet but not on the other, and people said they had better control over their cravings.
Eight weeks may sound short, but the researchers estimate that keeping up these trends for a year could mean about 9 to 13 percent weight loss on the minimally processed diet, against 4 to 5 percent on the ultra-processed one.
The findings are clear, following healthy eating advice helps, and choosing less processed food may help even more.
The Protocol
Follow the Eatwell Guide: Build meals around fruit and vegetables, wholegrain starchy foods, and protein such as beans, fish, eggs or meat. Both diets in the trial did this, and both led to weight loss.
Choose the less processed version: Swap packaged cereals and ready meals for simple foods you put together yourself, like porridge oats or a home-cooked stew.
Look past health claims: Many of the ultra-processed foods in the trial carried nutrition or health claims, so a healthy label does not mean the food is minimally processed.
PILLAR SPOTLIGHT · SLEEP & RECOVERY
Short Sleep May Open The Door To Colds
Feel like you catch every cold going? Your sleep might be part of the reason.
In a US study, researchers tracked the sleep of 164 healthy adults aged 18 to 55 with wrist trackers for a week. Then they put them in quarantine and gave them nose drops containing a common cold virus.
People who slept less than 5 hours a night were 4.5 times more likely to develop a cold than those who slept more than 7 hours. Sleeping 5 to 6 hours raised the odds 4.2 times. Those sleeping 6 to 7 hours were at no clear extra risk.
VIDEO OF THE WEEK
The Secret To A Good Life
Psychiatrist Robert Waldinger leads one of the longest studies of adult life ever run. After decades of tracking the same people, the clearest lesson has nothing to do with money or fame. It's about the people around us, and why good relationships keep us healthier and happier.
That's it for this week.
Swap one packaged meal for something simple you cook yourself. Aim for at least seven hours of sleep, especially when colds are going around. And watch Robert Waldinger's talk, then call a friend you have been meaning to catch up with. Small steps, and all of them easy to start.
Take care of yourself,
The Vitality Club
THE SUMMARY
Key takeaways
The UPDATE trial, published in Nature Medicine in 2025, gave 55 adults in England two 8-week diets in random order, both following the NHS Eatwell Guide.
Weight fell 2.06 percent on the minimally processed diet and 1.05 percent on the ultra-processed diet.
The minimally processed diet also cut fat mass by about 0.98 kg more, lowered triglycerides and improved craving control.
The trial was small, 91 percent of participants were women, and LDL cholesterol fell more on the ultra-processed diet.
In 164 healthy adults given a cold virus, those sleeping under 5 hours were 4.5 times, and those sleeping 5 to 6 hours 4.2 times, more likely to catch a cold than those sleeping over 7 hours.
Sources
Dicken SJ, et al. (2025). Ultraprocessed or minimally processed diets following healthy dietary guidelines on weight and cardiometabolic health: a randomized, crossover trial. Nature Medicine.
Prather AA, et al. (2015). Behaviorally assessed sleep and susceptibility to the common cold. Sleep.
About the authors
The Vitality Club is written by PhD researchers at Durham University, Marcus W, Camila G and Todd B, who turn new peer-reviewed health and longevity research into practical takeaways. This article is for education only and is not medical advice; talk to a qualified healthcare professional before changing your diet, exercise, supplements or medication.