Blueberry Supplementation in Midlife for Dementia Risk Reduction

Nutrients. 2022 Apr 13;14(8):1619. doi: 10.3390/nu14081619.

Abstract

Late-life dementia typically develops over a period of many years beginning in midlife. Prevalence of metabolic disturbance also accelerates in middle age and is a prominent risk factor for dementia. Preliminary studies indicate that blueberry supplementation can improve cognitive performance and influence metabolism and brain function and therefore may have a role in early intervention to prevent neurodegeneration. In a randomized controlled trial, we investigated the effects of daily blueberry supplementation in a middle-aged sample of insulin-resistant participants with elevated risk for future dementia. We enrolled overweight men and women, aged 50 to 65 years, with subjective cognitive decline (SCD) and performed pre- and post-intervention assessments of cognition and metabolism and exploratory measures of peripheral mitochondrial function. We observed improved performances for the blueberry group on measures of lexical access, p = 0.003, and memory interference, p = 0.04, and blueberry-treated participants reported reduced memory encoding difficulty in daily life activities, p = 0.03. The blueberry-treated group also exhibited correction of peripheral hyperinsulinemia, p = 0.04, and a modest trend for increased mitochondrial uncoupling, p = 0.11. The cognitive findings indicated improved executive ability in this middle-aged sample. In addition, the changes in metabolic and bioenergetic measures imply potential mechanistic factors associated with anthocyanin and proanthocyanidin actions. The demonstration of these benefits in middle-aged individuals with insulin resistance and SCD suggests that ongoing blueberry supplementation may contribute to protection against cognitive decline when implemented early in at-risk individuals.

Keywords: BMI; cognition; insulin resistance.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Blueberry Plants*
  • Cognition
  • Cognitive Dysfunction* / epidemiology
  • Cognitive Dysfunction* / prevention & control
  • Dementia* / epidemiology
  • Dementia* / prevention & control
  • Dietary Supplements
  • Female
  • Humans
  • Male
  • Middle Aged
  • Risk Reduction Behavior