MELBOURNE, Australia — Higher intake of ultraprocessed foods was linked to lower attention scores and higher modifiable dementia risk scores in a new study of more than 2,100 dementia-free Australian adults, researchers reported April 24, 2026. The findings suggest that the degree of food processing may matter for brain health even when people otherwise follow healthier eating patterns, April 24, 2026.
The study, published in Alzheimer’s & Dementia: Diagnosis, Assessment & Disease Monitoring, analyzed 2,192 adults ages 40 to 70. Researchers classified diets using the Nova food-processing system, measured cognition with a computerized test battery and estimated dementia risk through a score based on modifiable health factors.
For every 10% increase in ultraprocessed food intake, participants had lower attention scores and higher dementia risk scores. The association remained after researchers accounted for adherence to a Mediterranean-style diet, suggesting that processing itself may be a separate concern from overall diet quality.
How ultraprocessed foods were tied to attention
Ultraprocessed foods include products such as soft drinks, packaged salty snacks, ready-made meals, processed meats and many sweetened dairy desserts. Monash University said the 10% increase was roughly comparable to adding a standard packet of potato chips to a daily diet.
Lead author Dr. Barbara Cardoso, of Monash University, said researchers saw a “distinct and measurable drop” in the ability to focus as ultraprocessed food intake rose. The decline appeared in tests measuring visual attention and processing speed, not in memory tests.
That distinction matters because attention helps support learning, problem-solving and everyday decision-making. Still, the study was observational and cross-sectional, meaning it captured a point in time and cannot prove that ultraprocessed foods caused poorer focus or higher dementia risk scores.
Why ultraprocessed foods keep appearing in brain health research
The new findings add to a line of research that has been building for several years. In 2022, a prospective cohort study in Neurology found that higher ultraprocessed food consumption was associated with higher risks of dementia, Alzheimer’s disease and vascular dementia among older adults in the U.K. Biobank.
In 2023, a JAMA Neurology study of 10,775 adults in Brazil reported that higher ultraprocessed food consumption was associated with faster global and executive function decline over a median follow-up of eight years. Executive function includes skills such as planning, attention and task-switching.
A 2024 Harvard Health article also highlighted research connecting higher ultraprocessed food intake with increased risk of cognitive impairment and stroke, while noting that people who ate more minimally processed foods appeared to have better brain health outcomes.
What the study did and did not show
The researchers did not find a significant association between ultraprocessed food intake and memory loss. They also noted that self-reported diet data can be imperfect because people may forget, underestimate or misclassify what they eat.
The dementia score used in the study reflects risk factors that can be changed, such as obesity and high blood pressure. It is not the same as a dementia diagnosis, and the findings should not be read as proof that a daily packaged snack will directly cause dementia.
Even so, the results point to a practical public health message: reducing ultraprocessed foods may be one manageable way to support long-term brain health, especially in midlife, when many dementia risk factors begin to accumulate.
Simple swaps may help lower exposure
Experts generally recommend replacing heavily processed snacks and ready-to-eat meals with foods that are closer to their original form. Examples include fruit, vegetables, beans, nuts, whole grains, fish, eggs and minimally processed dairy or meat products.
Small changes may be more realistic than a total overhaul. Swapping a packaged salty snack for nuts, replacing sugary drinks with water or choosing a homemade meal instead of a ready-made entrée can reduce daily exposure to additives, refined starches, excess salt and added sugars commonly found in ultraprocessed foods.
The latest research does not close the case on diet and dementia. It does, however, strengthen the warning that the daily convenience of ultraprocessed foods may come with a cost for attention and long-term brain health.
