GCG and type 2 diabetes mellitus: In a study by Takeuti et al., T2DM patients consumed 30 g of glutamine diluted in 200 ml of water for one day, and the authors observed a significant reduction in blood glucose 2 h after the ingestion of glutamine; however, blood glucose 1 h afterward and PYY and GLP-1, 1 and 2 h after glutamine consumption showed no significant changes.