JAMA Network Open: Everyday Diet May Reduce Dementia Risk by Nearly One-Third

A new study published in JAMA Network Open suggests that a diet rich in anti-inflammatory foods may significantly reduce the risk of developing dementia, particularly in people with a higher biological predisposition to Alzheimer's disease.

Researchers found that older adults with early biomarkers of Alzheimer's disease who followed an anti-inflammatory diet had up to a 29% lower risk of developing dementia. The findings are based on data from nearly 1,900 participants enrolled in a Swedish aging study who were followed for 15 years.

At the start of the study, all participants were over the age of 60 and showed no signs of dementia. During the follow-up period, they underwent up to six clinical assessments, which included dietary evaluations and blood sample collection.

The researchers focused on three key biomarkers associated with Alzheimer's disease and neurodegeneration:

• Tau protein, which forms toxic aggregates in the brain when it accumulates abnormally.

• Neurofilament light chain (NfL), a marker of neuronal injury and degeneration.

• Glial fibrillary acidic protein (GFAP), which reflects the activation of supportive brain cells in response to damage.

The results showed that among participants with elevated levels of these biomarkers, adherence to an anti-inflammatory diet was associated with a 21% to 29% lower risk of dementia, depending on the specific biomarker.

According to the study authors, a diet with low inflammatory potential may benefit not only the general population but also individuals who are already at increased risk of cognitive decline.

Registered dietitian Emily Case, who reviewed the findings, noted that the growing body of scientific evidence increasingly supports the role of nutrition in Alzheimer's disease prevention. She emphasized that diet should be considered part of a comprehensive prevention strategy that also includes regular physical activity and adequate sleep.

Anti-inflammatory foods are commonly found in dietary patterns such as the Mediterranean diet and the DASH diet. These include:

• Berries and dark leafy greens rich in antioxidants.

• Fish and walnuts, which provide omega-3 fatty acids.

• High-fiber foods, including whole grains, legumes, fruits, and vegetables.

• Healthy fats from olive oil, avocados, and nuts.

Experts also point out that while genetic predisposition plays an important role in the development of neurodegenerative diseases, lifestyle choices—including diet—can substantially influence how these risks manifest.

Overall, the study highlights that although a healthy diet cannot completely eliminate the risk of dementia, it may help delay its onset and reduce the likelihood of severe disease progression.