Anti-Inflammatory Diet May Lower Dementia Risk in People With Early Alzheimer's Biomarkers: Study

Researchers conducted tests using an extensive sample of elderly people from the famous Swedish National Study on Aging and Care in Kungsholmen (SNAC-K). The cohort study consisted of community-dwelling subjects aged 60 years or more between March 2001 and August 2004 and had them undergo multiple medical, clinical, and nutritional examinations over the course of 6 waves, which lasted until February 2016 to November 2019. First data analyses were done in September 2024 to August 2025, followed by rigorous statistical re-analyses performed in March and April 2026.

For the initial analyses, blood samples were taken for determining serum levels of three important high-resolution neurobiological biomarkers: phosphorylated tau at threonine 217 (p-tau217) to assess active Alzheimer amyloid-tau pathology; neurofilament light chain (NFL) for monitoring widespread axonal neurodegeneration; and glial fibrillary acidic protein (GFAP) for measuring destructive reactive astrogliosis and brain inflammation. Over 6 years, researchers were monitoring compliance of participants regarding three reliable patterns of healthy diets: the Alternate Mediterranean Diet (AMED), the Alternative Healthy Eating Index (AHEI), and the reverse Empirical Dietary Inflammatory Index (rEDII). The main endpoint was the incidence of all-cause dementia, while the secondary endpoint was Alzheimer dementia incidence.

Key findings:

• The mean baseline age of participants amounted to 70.5 ± 9.3 years, and, additionally, the population contained a vast majority of females – 1,125 subjects or 60.3% of the total study group.
• Over an average follow-up period of 8.4 years ranging from under 0.1 to 15.9 years, there was a total of 240 subjects that developed a condition of clinical all-cause dementia.
• In the case of participants with increased p-tau217 levels, a 1–z-score increase in compliance with an anti-inflammatory diet resulted in a remarkably protective hazard ratio of 0.71 (95% CI, 0.58-0.88).
• As for participants with elevated NFL concentrations, an increase in adherence to the rEDII diet resulted in a lower hazard ratio of 0.79 (95% CI, 0.66-0.95).
• Additionally, in the case of patients with elevated GFAP concentrations, a 1–z-score increase in adherence to the anti-inflammatory diet led to an extremely protective hazard ratio of 0.73 (95% CI, 0.60-0.89).
• In contrast to the aforementioned results, positive associations between the general AMED and AHEI dietary patterns and reduced dementia risk occurred only among participants with low baseline biomarker levels.

Overall, the results from this cohort study on elderly patients have revealed that following a less-inflammatory diet was linked with reduced dementia risk in people with Alzheimer's disease pathology and neurobiological risk factors. This result highlights the need for the implementation of diet-based dementia prevention measures not just for the entire population but especially for those who are already at increased risk. These definitive decades-long observations make up an integral empirical base for contemporary preventative neurology, showing that it is still possible to influence the development of dementia through lifestyle changes even when microscopical brain damage has started.

Reference:

Mrhar A, Carballo-Casla A, Grande G, et al. Diet Quality and Dementia Risk in Older Adults With Alzheimer Pathology. JAMA Netw Open. 2026;9(6):e2620254. doi:10.1001/jamanetworkopen.2026.20254