Ultraprocessed Foods May Affect Attention and Dementia Risk
A new study links higher ultraprocessed food intake with poorer attention and higher estimated dementia risk in middle-aged and older adults.
A cross-sectional study of nearly 2200 dementia-free Australian adults found that higher ultraprocessed food intake was associated with lower attention scores and higher estimated dementia risk, even after accounting for Mediterranean diet adherence.
The study did not find a significant link between ultraprocessed food intake and memory scores.
Study Details
Ultraprocessed foods are packaged or industrially formulated foods that often contain added sugars, refined starches, fats, flavorings, emulsifiers, and other additives. Common examples include soft drinks, sweetened beverages, packaged snacks, dairy-based desserts, and many ready-to-eat foods.
This study focused on adults aged 40 to 70 years enrolled in the Healthy Brain Project in Australia between 2016 and 2023. The participants were dementia-free at the time of the study, with an average age of 57 years. Most participants were women, White, and had higher education or socioeconomic status, which is important when thinking about how broadly the results apply.
The most consumed ultraprocessed foods in the study were dairy-based desserts and drinks, followed by soft drinks, fruit drinks, and other sweetened beverages.
Methodology
Researchers looked at participants’ usual food intake over the previous 12 months using a validated food frequency questionnaire. They estimated how much of each person’s diet came from ultraprocessed foods and also measured how closely they followed a Mediterranean-style diet.
Cognitive performance was measured using the Cogstate Brief Battery, which evaluated processing speed, visual attention, visual recognition memory, working memory, and attention. The researchers then created attention and memory composite scores. Dementia risk was estimated using the Cardiovascular Risk Factors, Aging, and Incidence of Dementia tool.
The analysis adjusted for age, sex, physical activity, smoking status, cardiometabolic disease history, body mass index, and Mediterranean diet adherence. This matters because the study tried to separate the effect of ultraprocessed foods from overall diet quality.
Key Findings
Higher ultraprocessed food intake was associated with a higher modified dementia risk score.
Each 10% increase in ultraprocessed food intake was linked to a measurable decrease in attention scores.
The attention association remained significant even after adjusting for Mediterranean diet adherence.
People whose ultraprocessed food intake made up more than 28% of total grams consumed had lower attention scores than those whose intake was 13% or less.
No significant association was found between ultraprocessed food intake and memory scores.
Implications for Practice
For patients and families, the practical message is not that one snack causes dementia. The study shows an association, not proof of causation. Still, it adds to a growing body of evidence suggesting that diet quality may matter for brain health before dementia develops.
The most important finding is the attention signal. Attention and processing speed are daily-life functions. They affect driving, reading, work performance, medication management, and the ability to follow conversations. A diet pattern high in ultraprocessed foods may be one modifiable factor worth addressing earlier in life, especially in middle age.
For healthcare providers, this study supports including food processing level in conversations about brain health, not just calories, sugar, sodium, or fat. It may be useful to ask patients how often they consume sweetened drinks, packaged desserts, chips, ready-to-eat snacks, and heavily processed convenience foods.
The Mediterranean diet adjustment is clinically interesting. Even when researchers accounted for Mediterranean diet adherence, ultraprocessed food intake still showed an association with attention and dementia risk. That suggests clinicians may need to look at both sides of diet quality: increasing protective foods such as vegetables, legumes, fish, nuts, and olive oil, while also reducing highly processed foods.
Important Limitations
This was a cross-sectional study, so it cannot prove that ultraprocessed foods directly caused poorer attention or higher dementia risk. It captures a snapshot in time.
The study population was also not fully representative. Participants were mostly women, White, better educated, and had higher socioeconomic status. Many also had a family history of dementia. The food questionnaire relied on self-reported intake, which can introduce recall errors.
These limitations mean the findings should be interpreted as a signal that deserves further study, not as final proof.
Practical Takeaway
For people concerned about dementia prevention, this study supports a simple and realistic goal: reduce ultraprocessed foods gradually, especially sweetened drinks, packaged desserts, and snack foods. Replacing even some of these foods with less processed options may be a reasonable brain-health step.
For clinicians, the study offers another reason to discuss diet quality with middle-aged adults before cognitive symptoms appear. The focus should be practical, nonjudgmental, and specific: identify the most frequent ultraprocessed foods in a patient’s diet and help them swap one category at a time.