Ultra-Processed Foods: What You Eat May Be Affecting Your Attention And Brain Health

Your brain may be suffering from what you eat every day. Scientists warn that ultra-processed foods may increase the risk of cognitive decline and dementia.

Ultra-processed foods are increasingly present in people's daily lives worldwide. Soft drinks, chips, filled cookies, ready-made meals, processed meats, and various industrialized products are part of the daily diet of millions of people.

These foods often contain many artificial ingredients, preservatives, flavorings, colorings, and large amounts of sugar, fat, and salt. Although they are convenient and inexpensive, scientists have been warning for years that frequent consumption of these products can cause serious harm to physical health. Now, new research also raises concerns about possible impacts on the brain.

Previous studies had already linked ultra-processed foods to cardiovascular disease, obesity, type 2 diabetes, depression, and even premature death. More recently, researchers have begun to investigate whether these foods could also influence memory, attention, and the risk of developing dementia in the future.

However, an important question remained: were the observed problems caused specifically by ultra-processed foods or simply by a poor diet in general?

To try to answer this question, Australian scientists analyzed data from more than two thousand people between 40 and 70 years old who participated in a large project on brain health. None of the participants had a diagnosis of dementia.

The researchers asked the volunteers to fill out detailed questionnaires about everything they usually ate throughout the day. From these answers, the foods were classified according to their level of industrial processing. Thus, the scientists were able to calculate how much of each person's diet consisted of ultra-processed products.

After that, the participants underwent computerized tests to assess different brain functions, such as attention, memory, and speed of reasoning. The researchers also used a scientific tool that estimates the future risk of developing dementia based on factors such as cardiovascular health, lifestyle, age, and general health habits.

Furthermore, the scientists took an important precaution: they separated the effect of ultra-processed foods from the overall quality of the diet. This allowed them to understand whether ultra-processed foods could affect the brain even in people who followed a diet considered relatively healthy.

The results showed that the higher the consumption of ultra-processed foods, the worse the attention-related performance. The study also found an increased estimated risk of dementia among people who consumed more of these foods. According to the researchers, the association remained even after considering factors such as adherence to the Mediterranean diet, frequently associated with brain protection and longevity.

Interestingly, scientists did not find a clear link between ultra-processed foods and memory, suggesting that some areas of brain function may be more sensitive than others to the effects of industrialized food.

The authors emphasize that further studies are needed to understand exactly how these foods may affect the brain over the years. Hypotheses include inflammatory processes, metabolic changes, impact on blood vessels, and possible effects of chemical additives present in processed products.

Even so, the results reinforce the idea that reducing the consumption of ultra-processed foods can be an important measure not only for the body but also to protect brain health during aging.

READ MORE:

Ultra-processed food intake, cognitive function, and dementia risk: A cross-sectional study of middle-aged and older Australian adults

Barbara R. Cardoso, Euridice Martinez Steele, Barbara Brayner, Xinyi Yuan, Lisa Bransby, Hannah Cummins, Yen Ying Lim, and Priscila Machado

Alzheimer’s & Dementia. Volume18, Issue2 April/June 2026 e70335DOI: 10.1002/dad2.70335

Abstract: 

Ultra-processed food (UPF) consumption is linked to over 30 adverse health outcomes, including several risk factors for dementia such as cardiovascular disease, type 2 diabetes, and obesity. We aimed to examine the association of UPF consumption with cognitive performance and dementia risk scores, and whether these associations are independent of overall diet quality. This cross-sectional analysis assessed 2,192 Australian dementia-free adults aged 40–70 years. Diet was assessed using a validated food frequency questionnaire and classified according to the Nova system. Cognitive function was measured using the Cogstate Brief Battery, and dementia risk was estimated with the CAIDE tool. Each 10% increase in UPF intake was associated with lower attention scores (−0.05 points) and higher dementia risk (+0.24 points), independent of Mediterranean diet adherence. Higher UPF consumption is associated with poorer attention and increased modifiable dementia risk, independent of overall diet quality.