FGF21 and Obesity: Indeed, previous publications implicated CerS1 and CerS5 in obesity and glucose intolerance (Hammerschmidt et al., 2019; Turpin et al., 2014; Turpin‐Nolan et al., 2019) (Gosejacob et al., 2016) Specifically, CerS1‐derived C18‐ceramide in skeletal muscle was shown to enhance whole‐body glucose metabolism in obesity by increasing the muscle‐derived adipokine Fgf21 (Turpin‐Nolan et al., 2019).