anti-inflammatory foods

Dietary Patterns and Cerebral Glucose Metabolism in Older Adults: Findings from the Western Australian Memory Study

1 April 2026

Castro CB, Gardener SL, Jahan F, Chen J, Brown BM, Loo RL, Taddei K, Rainey-Smith SR, Weinborn M, Dos Reis ACR, Verma S, Carrigan N, Inderjeeth C, Doré V, Garg ML, Martins RN, Sohrabi HR.

Summary

Plain-Language Summary

This study investigated how dietary habits influence brain energy levels (glucose metabolism) in older adults, a key marker of cognitive health. Researchers discovered that a "Western Diet" high in sugar and saturated fats significantly accelerated the decline of brain metabolism in regions vital for memory and processing, with these effects being most pronounced in women.

Key Findings

Brain Energy Decline: High adherence to a Western Diet was linked to a faster drop in glucose metabolism in the neocortex and prefrontal regions.
Sex-Specific Vulnerability: The negative impact of poor diet on brain metabolism was statistically significant in females but not in males.
Functional Impact: The decline occurred in brain areas responsible for essential tasks, including facial recognition and complex decision-making.
The "Prudent" Gap: Surprisingly, a "Prudent Diet" (rich in produce and whole grains) did not show a significant protective effect on brain metabolism within this specific study period.

Practical Takeaways

Prioritize Brain Fuel: Limiting highly processed foods, added sugars, and excessive saturated fats may help preserve the brain’s ability to metabolize energy as you age.
Early Intervention for Women: Given that women are at a higher risk for Alzheimer's, maintaining a high-quality diet is a critical preventative strategy for long-term neurological health.
Focus on "The Harmful" vs. "The Helpful": This research suggests that avoiding damaging foods (Western Diet) may be just as important as including healthy ones for maintaining brain metabolism.

Study Limitations

The study utilized self-reported food questionnaires, which can be subject to recall bias. Additionally, the relatively small sample size and three-year duration may have been insufficient to capture the full protective benefits of a healthy "Prudent" diet.

Abstract

Alzheimer's disease (AD) is characterized by significant reductions in glucose metabolism, reflecting underlying synaptic dysfunction, correlating with cognitive decline. We aimed to explore the impact of dietary patterns on the change in glucose metabolism.<h4>Methods</h4>This longitudinal, prospective study included 132 community-dwelling older adults without a diagnosed dementia history enrolled in the Western Australian Memory Study (WAMS). Participants completed a food frequency questionnaire at baseline and underwent [<sup>18</sup>F]-Fluorodeoxyglucose positron emission tomography (FDG-PET) imaging at baseline and at up to two follow-up assessments scheduled approximately 18 months apart, over a maximum follow-up period of 43 months. Principal component analysis yielded two dietary patterns-named Western Diet and Prudent Diet. Linear mixed-effect models evaluated the association between dietary adherence and glucose metabolism, including potential confounders. Analysis was repeated stratified by sex.<h4>Results</h4>Adherence to a Western Diet, characterized by high sugars and saturated fats, was associated with faster decline in glucose metabolism in the left fusiform gyrus (β = -0.00062; SE = 0.00025; FDR-adjusted <i>p</i> = 0.043), neocortex (β = -0.00063; SE = 0.00026; FDR-adjusted <i>p</i> = 0.047), left ventrolateral prefrontal (β = -0.00083; SE = 0.00032; FDR-adjusted <i>p</i> = 0.045 and inferior parietal region (β = -0.00344; SE = 0.00129; FDR-adjusted <i>p</i> = 0.033) in females. A Prudent Diet, characterized by a high intake of fruits, vegetables, and whole grains, showed no significant effects.<h4>Conclusions</h4>Our study highlights the following: (a) The potential detrimental impact of a Western Diet on brain glucose metabolism, particularly for females, who are at higher risk for AD. The decline was observed in regions essential for cognitive functions, including visual processing and facial recognition, emphasizing the role of diet in brain health. (b) No significant associations were observed between adherence to a Prudent dietary pattern and changes in glucose metabolism.

Source study →