Early exposure to unhealthy foods leaves lasting brain and feeding changes

Eating unhealthy foods early in life leave lasting brain and feeding changes but gut bacteria can help restore healthy eating, new University College Cork (UCC) research study finds today (Tuesday 24^th February 10am)

A high-fat, high-sugar diet during the early life period can cause long-lasting changes in how the brain regulates eating, even when the unhealthy diet is stopped and body weight is normalized, the researchers at APC Microbiome, a leading research institute, at UCC discovered.

Children today are growing up in food environments saturated with high-fat, high-sugar options that are readily accessible and heavily promoted. From birthday parties and school celebrations to sporting events and even as rewards for good behaviour, these foods have become a routine part of childhood experiences.

This new research highlights the long-term impact of this early exposure, demonstrating that frequent consumption of energy-dense, nutrient-poor foods in childhood can shape preferences and establish unhealthy eating patterns that persist well into adulthood.

Published today in Nature Communications, the study also demonstrates that microbiota-targeted interventions, including a specific strain of beneficial gut bacteria (Bifidobacterium longum APC1472) or prebiotic fibres (fructo-oligosaccharides (FOS) and galacto-oligosaccharides (GOS), naturally present in foods such as onions, garlic, leeks, asparagus and bananas, and widely available in fortified foods and prebiotic supplements), could help prevent these effects when administered throughout life.

The researchers found that exposure to a high-fat, high-sugar diet during early life in a preclinical mouse model led to persistent alterations in feeding behaviour in adulthood. These behavioural changes were linked to lasting disruptions in the adult hypothalamus, a key brain region involved in appetite control and energy balance.

What we eat early in life matters

Our findings show that what we eat early in life really matters. Early dietary exposure may leave hidden, long-term effects on feeding behaviour that are not immediately visible through weight alone."

Dr. Cristina Cuesta-Martí, first author of the study

The study showed that unhealthy diets early in life disrupted brain pathways involved in feeding behaviour, with effects lasting into adulthood, suggesting an increased risk of obesity later in life.

Importantly, targeting the gut microbiota helped counteract these long-term diet-related effects. The putative probiotic strain Bifidobacterium longum APC1472 produced marked improvements in feeding behaviour while inducing only minor changes in overall microbiome composition, suggesting a targeted mode of action. In comparison, the prebiotic combination (FOS+GOS) drove broader shifts in the gut microbiome.

Targeting the gut microbiota can mitigate the long-term effects

Dr Harriet Schellekens, lead investigator of the study, added: "Crucially, our findings show that targeting the gut microbiota can mitigate the long-term effects of an unhealthy early-life diet on later feeding behaviour. Supporting the gut microbiota from birth helps maintain healthier food-related behaviours into later life."

Professor John F. Cryan, Vice President for Research & Innovation at UCC and collaborator on the study, said: "Studies like this exemplify how fundamental research can lead to potential innovative solutions for major societal challenges. By revealing how early-life diet shapes brain pathways involved in the regulation of feeding, this work opens new opportunities for microbiota-based interventions."

The UCC led study was in partnership with collaborators at the University of Seville (Spain), University of Gothenburg (Sweden) and Teagasc Food Research Centre (Fermoy, Ireland), and funded by Research Ireland, a Government of Ireland Postgraduate Scholarship and a research award from the Biostime Institute for Nutrition & Care.