SCOPE: Green leafy vegetables (GLV) may improve postprandial glycaemic responses (PGR) and metabolic health. However, inter-individual variations (IIV) preclude conclusive evidence. Sirtuin system is emerging as a key player in blood glucose control. This study investigated IIV in PGR in women co-ingesting GLV with a carbohydrate meal and interactions with the sirtuin system.
METHODS AND RESULTS: Volunteers (n = 31 women) consumed rice, rice with bok choy or spinach (75g available carbohydrate) on separate occasions. Postprandial glucose, insulin, adropin and lipid levels were measured. Anthropometric measurements and sex hormones were measured. GeXP assay measured whole blood postprandial gene expression profiles of 25 markers involved in sirtuin signalling. GLV consumption had no significant effect on PGR which showed high variation. PGR correlated with age, but no other consistent associations were observed. Sirtuin gene expression profiles revealed distinct stratified subgroups associated with PGR, lipid, insulin, fat mass, waist/hip circumferences and adropin levels.
CONCLUSION: PGR to co-ingesting GLV with a carbohydrate meal were highly variable in this cohort and failed to reveal a significant reduction in PGR. Variable responses were largely independent of menopausal status and meal consumed. However, lower expression of sirtuin gene targets was associated with higher PGR and with markers linked to health status. This article is protected by copyright. All rights reserved.
Bibliographical noteThe authors acknowledge the support of the Scottish Government Rural and Environment Science and Analytical Services (RESAS) Strategic Research Programme. Clinical biochemistry lab at the Foresterhill hospital for analysing sex hormone samples, Human Nutrition Unit staff and analytical staff and the Rowett Institute, University of Aberdeen and Alex Stewart for providing the compositional information for the meal interventions used. Finally, we would like
to thank the volunteers participating in VegGI study.
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- inter‐individual variation
- postprandial glycaemia