Consumption of ultraprocessed foods (UPFs) is significantly associated with an increased risk of dementia and a measurable decline in attention span, according to new research published in the journal Alzheimer’s and Dementia.
The study, conducted by researchers at Australia’s Monash University, analyzed more than 2,000 dementia-free adults between the ages of 40 and 70. The findings reveal that every 10% increase in UPF intake—roughly equivalent to eating one package of chips per day—is tied to higher dementia risk and lower attention scores.
Notably, this increased risk was observed regardless of whether the individuals otherwise maintained a healthy diet, such as the Mediterranean diet. While attention scores were impacted, researchers found no significant link between UPF consumption and memory.
“Your brain is an energy-hungry organ,” said Dr. Daniel Amen, a brain disorder specialist and psychiatrist, in an interview regarding the findings. He noted that because the brain consumes approximately 20% of a person’s daily calories, the quality of those calories is critical.
UPFs, which include packaged snacks, sugary soft drinks, and ready-made meals, are often high in additives, unhealthy fats, and sugar. These ingredients can promote inflammation, insulin resistance, and oxidative stress, all of which are considered “bad for the brain.” Amen emphasized that even small amounts of these foods can have measurable effects, stating that attention is the “gateway” to learning and decision-making.
The researchers suggested the study highlights a need to refine dietary guidelines to account for food processing levels. However, the team also noted a limitation in the study: the data was based on self-reported dietary habits, which can affect the strength of the findings.
To mitigate risks, health experts recommend replacing one ultraprocessed item daily with “brain-healthy” options such as nuts, seeds, clean proteins, and colorful vegetables. For individuals with a family history of cognitive decline or existing conditions like diabetes and high blood pressure, experts warn that diet should be treated as a “primary brain-health intervention” rather than a secondary concern.