Increasing daily consumption of ultraprocessed foods by 10%—roughly the equivalent of a small bag of potato chips—may elevate the risk of dementia, even for individuals who typically follow a healthy, plant-rich diet, according to a new study, reports BritPanorama.
Ultraprocessed foods, or UPFs, account for about 53% of all calories consumed by adults in the United States, as per data from the US Centers for Disease Control and Prevention. In children, the proportion is even higher, with nearly 62% of their energy intake stemming from UPFs.
Lead author Barbara Cardoso, a senior lecturer in nutrition dietetics and food at Monash University in Melbourne, Australia, stated, “Our study showed that UPF consumption was associated with worse attention and higher dementia risk in middle-aged and older adults.” However, the study could demonstrate an association rather than direct causation.
Cardoso elaborated that the association remained consistent regardless of adherence to the Mediterranean diet, suggesting that this link pertains more to food processing than to displacement of healthier food options. The findings align with earlier research indicating that a 10% increase in UPF intake correlates with a 16% rise in cognitive impairment risk.
Dr. W. Taylor Kimberly, a professor of neurology at Harvard Medical School, not involved in the study, described it as an “important addition” to the body of evidence regarding the cognitive risks associated with ultraprocessed foods. Kimberly, who authored a related study published in January, stated, “Together these studies highlight that higher UPF consumption is consistently associated with poorer cognitive performance.”
Kimberly noted a potential upside for those willing to reduce their UPF intake over time. His study revealed that replacing ultraprocessed foods with minimally processed and whole foods over a five- to six-year period was associated with a 12% lower risk of cognitive decline.
Research has increasingly shown the dangers of ultraprocessed foods. A February 2024 review of 45 studies involving approximately 10 million individuals indicated that every additional 10% of UPF in one’s diet could substantially increase the risk of developing various health conditions, including cardiovascular disease, mental disorders, and obesity.
Real versus predigested food
The sought-after Mediterranean diet, which prioritizes whole grains, fruits, vegetables, beans, seeds, nuts, and extra-virgin olive oil, has also been linked to reduced risks of serious health issues such as cancer, heart disease, and dementia, especially for those possessing two copies of the APOE4 gene, a known Alzheimer’s risk factor.
Other notable plant-based diets, including the DASH diet and MIND diet, emphasize the consumption of whole foods while minimizing sugar, red meat, and ultraprocessed foods—each related to improvements in various health metrics.
In contrast, ultraprocessed foods consist of little to no whole food content, often being composed of derived elements that are chemically altered with additives to create products that depart significantly from their original forms. Such “predigested” foods are often high in sugar, salt, and fat and may lack essential nutrients beyond what is necessary for healthy bodily and brain function.
Furthermore, a 2022 study examining 10,000 individuals found that those consuming the most ultraprocessed foods had a 25% faster decline in executive function and a 28% faster rate of overall cognitive impairment compared to those eating the least.
Attention span and dementia risk
A recent study published in the journal Alzheimer’s & Dementia: Diagnosis, Assessment & Disease Monitoring surveyed over 2,100 Australians aged 40 to 70, finding that approximately 42% of their typical diet comprises ultraprocessed foods. Participants completed food diaries while undergoing cognitive testing to assess attention span and processing speed.
Cardoso indicated, “For every 10% increase in ultra-processed food a person consumed, we saw a distinct and measurable drop in a person’s ability to focus.” Although direct links between UPFs and memory issues were not identified, the study measured overall mental decline using a validated scoring tool designed to predict 20-year dementia risk.
Notably, each 10% increase in daily UPF consumption was associated with a 0.24 point rise in dementia risk on a scale ranging from 0 to 7 points, underscoring how ultraprocessed foods can accumulate in a daily diet.
Cardoso emphasized the importance of eliminating ultraprocessed foods from diets to mitigate risk, particularly before any neurological complications arise. “Midlife is a stage that offers a key opportunity to address modifiable risk factors before neuropathological changes compatible with dementia develop,” she concluded.
The ongoing discourse surrounding ultraprocessed foods illustrates the importance of dietary choices in cognitive health, signaling a need for greater public awareness on the implications of food processing on overall wellbeing.
