Same calories. Same macros. Different effects on your metabolism and brain. New research is challenging how we think about ultra-processed food.
We knew this long before it made headlines. When we started Chief, we believed that real food matters, and what we put into our bodies affects far more than just our waistlines. We were concerned about the growing dominance of ultra-processed foods and their potential impact on our physical and mental health and wanted to challenge the idea that convenience had to come at the expense of nutrition. We started Chief to create convenient, genuinely nutritious foods made with real ingredients and without unnecessary additives. Now, the science is catching up, and the findings are increasingly difficult to ignore.
Our modern food environment has changed dramatically. Ultra-processed foods (UPFs) are everywhere, including products marketed as healthy, high-protein or nutritious. Today, approximately 42% of calories consumed in Australia and 55% in the United States come from ultra-processed foods. If you're wondering what actually qualifies as ultra-processed food, read our article on the NOVA food classification system.
Higher consumption of UPFs has consistently been linked to poorer health outcomes, including cardiovascular disease, obesity, type 2 diabetes, certain cancers, depression and anxiety. But researchers are now uncovering something even more interesting. Food processing may change how our bodies absorb and metabolise nutrients, and how our brains respond to food.
Even when foods contain similar ingredients and nutritional profiles, processing differences can alter their physical structure, nutrient availability, and physiological effects. A fascinating new study has shown just that.
New 2026 study: ultra-processed foods change how your body and brain respond
A study published in Nature Metabolism in October 2026 examined what happened when 57 healthy adults consumed ultra-processed versus minimally processed meals carefully matched for calories, protein, carbohydrates, fat and several other nutritional characteristics.
The findings? Despite similar nutritional profiles, the meals triggered significantly different metabolic and brain responses.
Compared with minimally processed meals, ultra-processed meals:
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Triggered significantly higher insulin responses, despite similar overall blood glucose exposure.
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Kept blood glucose elevated for longer, although total glucose exposure was similar.
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Increased post-meal energy expenditure, meaning the body burned more energy during the period following consumption.
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Altered fuel metabolism, with reduced carbohydrate oxidation and increased fat oxidation.
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Produced different brain responses in regions involved in motivation, reward and food valuation.
Perhaps the most fascinating finding was the difference in brain activity. Researchers observed changes in how the brain responded to food cues, including activity in the striatum, a region involved in reward and motivation. In other words, two meals can look almost identical on a nutrition label, yet your body and brain may respond to them very differently.
Importantly, this was a short-term study. It demonstrated different physiological responses, not that a single ultra-processed meal causes brain damage or metabolic disease. The findings on higher energy expenditure and fat oxidation are not inherently harmful.
But it raises an important question. If processing changes how our bodies and brains respond to a single meal, what might years of relying heavily on ultra-processed foods mean for our health?
Read the original 2026 study:
https://doi.org/10.1038/s42255-026-01619-4
This isn't the first study to raise concerns about ultra-processed foods. The research has been accumulating for years.
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Research links ultra-processed foods to cognitive decline and dementia
Large-scale observational research from 2026 has associated higher ultra-processed food consumption with greater risks of cognitive impairment and dementia. These findings do not establish causation, but add to growing concerns about diet and long-term brain health.
Read the study:
https://pmc.ncbi.nlm.nih.gov/articles/PMC13277461/
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Minimally processed foods produced almost twice the percentage weight loss.
A randomised trial published in Nature Medicine in 2025 found that participants lost 2.06% of their body weight on a minimally processed diet, compared with 1.05% on an ultra-processed diet over eight weeks, even though both diets followed healthy eating guidelines.
Read the study:
https://doi.org/10.1038/s41591-025-03842-0
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Research involving nearly 10 million people revealed a concerning pattern.
A major review published in The BMJ in 2024 linked higher ultra-processed food consumption with increased risks of cardiovascular disease, type 2 diabetes, mental health disorders and premature death. While observational studies cannot prove cause and effect, the findings add weight to concerns about diets dominated by UPFs.
Read the study:
https://www.bmj.com/content/384/bmj-2023-077310
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Ultra-processed diets led people to eat approximately 500 extra calories a day
In a controlled trial conducted in 2019 by the US National Institutes of Health, participants spontaneously consumed around 500 more calories daily on an ultra-processed diet and gained approximately 0.9 kg in just two weeks. On the unprocessed diet, they lost approximately 0.9 kg.
Read the study:
https://doi.org/10.1016/j.cmet.2019.05.008
Why this matters, and why we started Chief
Not all food processing is harmful. Cooking, freezing, fermenting, and drying are all forms of processing, and some can actually improve food safety and nutrient availability. The concern is the growing reliance on industrially formulated ultra-processed foods, particularly those with poor nutritional quality.
At Chief, we've always believed that food should be judged by more than its calorie count or protein content. Ingredients matter. Food quality matters. And increasingly, science shows us that how food is processed matters too. We started Chief because we believed convenient food could be better. Made with real ingredients, thoughtfully formulated and designed to nourish the body rather than simply fill a gap in the market.
We're glad to see public awareness growing and research revealing more about the relationship between ultra-processed foods, metabolic health and the brain.
Real food. Real ingredients. Backed by science.
