Objective: The purpose of this study was to investigate the effects of supplementation with a spearmint (
Mentha spicata L.) extract, high in polyphenols including rosmarinic acid, on cognitive performance, sleep, and mood in individuals with age-associated memory impairment (AAMI).
Design: Subjects with AAMI (
N = 90; 67% female; age = 59.4 ± 0.6 years) were randomly assigned (
n = 30/group) to consume 900, 600, or 0 mg/day (two capsules, once daily) spearmint extract for 90 days, in this double-blind, placebo-controlled trial. Assessments were completed for cognition (days 0, 45, and 90), sleep (days 0 and 90), and mood (days 0 and 90) by using the Cognitive Drug Research (CDR) System
TM, Leeds Sleep Evaluation Questionnaire (LSEQ), and Profile of Mood States (POMS
Results: Quality of working memory and spatial working memory accuracy improved after supplementation with 900 mg/day spearmint extract by 15% (
p = 0.0469) and 9% (
p = 0.0456), respectively, versus placebo. Subjects consuming 900 mg/day spearmint extract reported improvement in their ability to fall asleep, relative to subjects consuming placebo (
p = 0.0046). Overall treatment effects were evident for vigor-activity (
p = 0.0399), total mood disturbance (
p = 0.0374), and alertness and behavior following wakefulness (
p = 0.0415), with trends observed for improvements after spearmint supplementation relative to placebo.
Conclusions: These results suggest that the distinct spearmint extract may be a beneficial nutritional intervention for cognitive health in older subjects with AAMI.