GLP1R and diabetes mellitus: Both incretins lose efficacy in the context of chronic elevated blood glucose seen in diabetes, but the somewhat better‐preserved effectiveness of GLP‐1 compared to GIP has been linked to GIPR‐downregulation (Zhou et al., 2007) or alternatively to a Gs to Gq‐coupling switch downstream of the GLP‐1, but not the GIP‐receptor (Oduori et al., 2020).