Researchers are developing new methods to understand how ultra-processed foods (UPF) affect the human body, with a specific focus on intestinal flora. Wilhelm Glomm, a researcher at SINTEF's Department of Biotechnology and Nanomedicine, is involved in this effort.## Challenges in Current ResearchExisting studies on UPF often use simplified approaches, such as replacing laboratory animal drinking water with a 1% emulsifier solution. Researchers state that this method may lead to incomplete conclusions about the effects of specific food components.The definition of ultra-processed food is not universally agreed upon. Multiple classification systems exist, including the NOVA system, which describes UPF based on criteria such as: * Ingredients primarily used by industry * Raw materials that have been broken down and then reconstituted * Added sugar, fat, and salt, often in combinationLack of a unified definition makes distinguishing UPF from less refined foods challenging.## Investigating Gut HealthResearchers suggest that examining the digestive system and the gut can provide more insights into UPF's effects. The gut contains over two-thirds of the body's immune system, and dietary intake significantly influences the gut microbiota, which includes bacteria, viruses, and fungi.Glomm's team conducted a clinical study to investigate gut health. They collected stool samples from volunteer women, men, and one infant. The composition of gut bacteria and the metabolites they generated were analyzed, and relationships between gut bacteria and differences in age, gender, and diet were examined.Metabolites are small molecules produced when living organisms, such as gut bacteria, digest nutrients. These can be health-promoting or linked to various diseases.## Key FindingsThe study identified significant differences in bacterial diversity between adults and infants, and confirmed that diet influences the composition of gut bacteria. A connection was observed between specific gut bacteria and the production of tryptamine, a metabolite associated with weight regulation and anti-inflammatory properties.Tryptamine production was traced to ruminococcus bacteria, which convert the amino acid tryptophan—found in protein sources like meat, eggs, fish, and dairy—into tryptamine. Individuals consuming these protein sources exhibited higher levels of tryptamine, while vegetarians had lower levels. This indicates that diet can impact intestinal bacteria and overall gut health.## Emulsifiers and Intestinal CellsEmulsifiers, or E-substances, are commonly used in ultra-processed foods to improve miscibility between oil and water. Some emulsifiers have been linked to health issues, including obesity and intestinal inflammation.Researchers investigated a selection of widely used emulsifiers at different concentrations, both with and without oil. When tested as a solution in water, emulsifiers caused damage to intestinal cells, dissolving the cell layer and, in some instances, killing the cells. However, when oil was present, minimal damage was observed. Similar results were found in experiments studying the effect of emulsifiers on a mixture of gut bacteria, where the impact was minimal if oil was present.Further research is needed to fully understand the health implications of emulsifiers. The study's findings are expected to contribute to identifying connections between food and health challenges such as intestinal inflammation, obesity, and diabetes.