The low glutamate diet improves cognitive functioning in veterans with Gulf War Illness and resting-state EEG potentially predicts response. (2nd November 2022)

• Record Type: Journal Article
• Authors: Kirkland, Anna E.; Baron, Michael; VanMeter, John W.; Baraniuk, James N.; Holton, Kathleen F.
• Is Part Of: Nutritional neuroscience. Volume 25:Number 11(2022)
• Page Start: 2247
• Page End: 2258
• Publication Date: 2022-11-02
• Subjects: Gulf War Illness -- cognitive functioning -- electroencephalography (EEG) -- glutamate -- dietary intervention; Neuropharmacology -- Periodicals; Diet -- Periodicals; Diet therapy -- Periodicals; Nutrition -- Periodicals; 615.78
• DOI: 10.1080/1028415X.2021.1954292
• Languages: English
• ISSNs: 1028-415X

Abstract

ABSTRACT: Objectives: Gulf War Illness (GWI) is a chronic, multi-symptom disorder with underlying central nervous system dysfunction and cognitive impairments. The objective of this study was to test the low glutamate diet as a novel treatment for cognitive dysfunction among those with GWI, and to explore if baseline resting-state electroencephalography (EEG) could predict cognitive outcomes. Methods: Cognitive functioning was assessed at baseline, after one-month on the diet, and across a two-week double-blind, placebo-controlled crossover challenge with monosodium glutamate (MSG) relative to placebo. Results: Significant improvements were seen after one-month on the diet in overall cognitive functioning, and in all other domains tested (FDR p < 0.05), except for memory. Challenge with MSG resulted in significant inter-individual response variability ( p < 0.0001). Participants were clustered according to baseline resting-state EEG using k-means clustering to explore the inter-individual response variability. Three distinct EEG clusters were observed, and each corresponded with differential cognitive effects during challenge with MSG: cluster 1 had cognitive benefit (24% of participants), cluster 2 had cognitive detriment (42% of participants), and cluster 3 had mild/mixed effects (33% of participants). Discussion: These findings suggest that the low glutamate diet may be a beneficial treatment for cognitive impairment in GWI. Future research is needed to understand the extent to which resting-state EEG can predict response to the low glutamate diet and to explore the mechanisms behind the varied response to acute glutamate challenge.