Anti-inflammatory diet supports brain health in people with cardiometabolic diseases

Among people with cardiometabolic diseases (CMD), diets with lower inflammatory potential contribute to larger gray matter and smaller white matter hyperintensity volumes, as well as reduced risk of dementia, according to a study.

For the study, researchers used data from the UK Biobank and identified 84,342 dementia-free older adults (mean age 64.1 years, 51.2 percent female). These participants were followed for 15 years, with a subsample of 8,917 having undergone brain MRI scans.

Baseline CMDs, such as type 2 diabetes, heart disease, and stroke, were ascertained using medical records. Average intake of 31 nutrients by the participants was assessed up to five times using the Oxford WebQ, a web-based 24-hour dietary assessment. The resulting data were used to calculate Dietary Inflammatory Index scores, which were categorized as follows: anti-inflammatory (≤−1.5 points), neutral (>−1.5 to <0.5 points), or proinflammatory (≥0.5 points).

Of the participants, 14,079 (16.7 percent) had at least one CMD at baseline. A total of 1,559 individuals (1.9 percent) received a diagnosis of dementia over a median follow-up of 12.4 years. Joint effect analysis showed that compared with CMD-free participants with an anti-inflammatory diet, participants with CMDs and a proinflammatory diet had the highest risk of dementia (hazard ratio [HR], 2.38, 95 percent confidence interval [CI], 1.93–2.93), followed by those with CMDs and a neutral diet (HR, 1.91, 95 percent CI, 1.57–2.32), and those with CMDs and an anti-inflammatory diet (HR, 1.65, 95 percent CI, 1.36–2.00).

Among participants with CMDs, an anti-inflammatory diet was associated with a 31-percent decreased risk of dementia as compared with a proinflammatory diet (HR, 0.69, 95 percent CI, 0.55–0.88; p=0.003).

Brain MRI findings showed that participants with CMDs and an anti-inflammatory diet additionally had significantly larger gray matter volume (β = −0.15; 95% CI, −0.24 to −0.06 vs β = −0.27; 95% CI, −0.38 to −0.16) and smaller white matter hyperintensity volume (β = 0.05; 95% CI, −0.04 to 0.14 vs β = 0.16; 95% CI, 0.05-0.27) compared with their counterparts with a proinflammatory diet.