Ultra-Processed Foods Linked to Brain Damage, Stroke Risk, Study Finds

High consumption of ultra-processed foods, such as soft drinks, packaged snacks, and sugary breakfast cereals, is associated with an increased risk of stroke and future memory problems, according to a recent study by Canadian researchers.

The study, published in JAMA Network Open, examined the brains of approximately 9,000 participants using magnetic resonance imaging (MRI) scans. Researchers identified small areas of brain damage more frequently in individuals who consumed large quantities of ultra-processed foods. Those with the highest intake were 40% more likely to exhibit these brain changes, which can go unnoticed as they often lack obvious symptoms.

These brain alterations can serve as early indicators years before the onset of stroke or memory decline. Russel J. de Souza, an associate scientist at the Population Health Research Institute (PHRI) of McMaster University and Hamilton Health Sciences and the study's first author, noted that these findings were unexpected, as such damage is typically associated with much older age groups. The study focused on middle-aged Canadians who reported no pre-existing heart conditions or other health concerns.

Participants in the study, aged between 35 and 69, who consumed the most ultra-processed foods also had higher body fat and visceral fat, which is linked to health issues including heart disease. The study observed a particularly strong connection between ultra-processed food consumption and brain damage in women. Those in the highest consumption group showed nearly double the likelihood of brain damage indicators compared to the lowest consumption group.

Sonia Anand, a senior scientist at PHRI and the study's senior author, stated that the findings suggest the link between diet and brain health may be detectable before noticeable memory or thinking problems arise. Ultra-processed foods are often low in essential nutrients like fiber, vitamins, and minerals, while being high in sodium, saturated fats, and added sugars, according to the CDC.

Data from August 2021 to August 2023 indicated that ultra-processed foods constituted about 55% of the daily calorie intake for Americans aged one year and older. For the participants in this specific study, ultra-processed foods accounted for approximately 25% of their daily intake. Conversely, whole foods such as fruits, vegetables, and grains made up a smaller proportion of the diet for those consuming higher amounts of ultra-processed items.

The researchers acknowledged that while the study revealed a connection between ultra-processed food consumption and indicators of brain changes, it could not establish a direct causal relationship. The participants were evaluated only once, and longer-term studies with repeated MRI scans are needed to determine if reducing intake of these foods can slow or prevent such brain changes. Follow-up research is reportedly in progress.