Location: Nutrition, Food Safety/Quality
Project Number: 0500-00117-001-006-A
Project Type: Cooperative Agreement
Start Date: Aug 1, 2026
End Date: Jul 31, 2027
Objective:
The objective of this study is to evaluate the efficacy of peanut consumption to improve cerebrovascular, cognitive, and physical function in adults with mild cognitive impairment (MCI). We will conduct a randomized, controlled crossover trial with 16-week intervention and control periods separated by an 8-week washout. Our central hypothesis is daily consumption of unsalted, skin-roasted peanuts will improve cognitive performance and physical function by enhancing cerebral blood flow (CBF) in adults with MCI.
Aim 1: Determine the effects of daily peanut consumption (2 oz/day) on global and domain-specific cognitive function. Hypothesis: Compared to isocaloric control, peanut consumption will improve cognitive performance assessed using the Montreal Cognitive Assessment (MoCA) and National Institutes of Health (NIH) Toolbox Cognition Battery.
Aim 2: Quantify the effects of daily peanut consumption (2 oz/day) on cerebrovascular function. Hypothesis: Compared to isocaloric control, peanut consumption will increase global CBF (assessed using pCASL magnetic resonance imaging [MRI]) and task-related neural activation (assessed using functional MRI).
Aim 3: Evaluate the effects of daily peanut consumption (2 oz/day) on body composition and physical function. Hypothesis: Compared to isocaloric control, peanut consumption will increase appendicular lean mass (measured by DXA), functional exercise capacity (assessed by 6-minute walk test), and physical performance (measured by Short Physical Performance Battery).
Approach:
The proposed study will be a randomized, single-blinded (outcome assessor–blinded), controlled crossover trial of daily peanut consumption in 40 adults with MCI. Participants will complete two 16-week intervention periods: (1) daily peanut consumption and (2) peanut-free, isocaloric control, separated by an 8-week washout to minimize potential carryover effects. Treatment sequence will be determined by computer-generated randomization, balancing the number of participants beginning with each intervention. Outcome assessments will be conducted at baseline and after each intervention period by trained investigators blinded to condition allocation.
A crossover design was selected to reduce between-subject variance and increase power by allowing each participant to serve as their own control. The 16-week intervention duration and 8-week washout are based on prior randomized controlled trials demonstrating improvements in CBF and cognitive function with nut and peanut consumption in older adults.