Effects of 12-week avocado consumption on cognitive function among adults with overweight and obesity

• Published in: International journal of psychophysiology Vol. 148; pp. 13 - 24
• Main Authors: Edwards, Caitlyn G., Walk, Anne M., Thompson, Sharon V., Reeser, Ginger E., Erdman, John W., Burd, Nicholas A., Holscher, Hannah D., Khan, Naiman A.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.02.2020
• Subjects: Attention; Carotenoids; Event-related potential; Obesity; Xanthophyll; Event-related potential; Obesity; Carotenoids; P3; N2; PUFA; Xanthophyll; MUFA; Attention; MPOD; HPLC; BMI
• ISSN: 0167-8760; 1872-7697
• DOI: 10.1016/j.ijpsycho.2019.12.006

Excess adiposity increases risk for cognitive impairment. Consumption of avocado, a highly bioavailable source of the xanthophyll lutein, has been shown to improve retinal lutein accumulation and cognitive function. Thus, we evaluated the influence of avocado consumption on cognitive function and lutein status among adults with overweight and obesity using a randomized-controlled trial with matching design for pertinent study outcomes. A cohort of 84 adults (25–45 years, 31 males) were randomized to a treatment group (N = 47) that received a 12-week daily meal with fresh Hass avocado or a control group (N = 37) that received an isocaloric meal (clinicaltrials.gov, NCT02740439). Serum lutein and macular pigment optical density (MPOD) were used to assess xanthophyll status. Attention and inhibition were assessed using the Flanker, Oddball and Nogo tasks with accompanying electroencephalographic (EEG) recording. Participants in the treatment group exhibited improvements in serum lutein and accuracy in the Flanker task. However, there were no relationships between performance and changes in lutein status, nor neuroelectric variables. No significant changes in MPOD were observed. Daily avocado intake over 12 weeks, after controlling for covariates, improved attentional inhibition and increased serum lutein concentrations among adults with overweight and obesity. However, the cognitive benefits were independent of changes in lutein concentrations. Additional work is necessary to determine non-carotenoid, or carotenoid interactive, mechanisms by which avocados may influence cognitive function. •Overweight and obesity have been linked to higher risk for cognitive impairment.•Improvements in diet have the potential to improve cognitive function.•Avocados provide lutein which has been shown to have neurocognitive potential.•A 12-week randomized-controlled trial tested the effects of avocado intake on cognitive control.•Avocado intake improved performance in attentional inhibition without changes in N2 and P3.