Moreover, HSL phosphorylation at Ser563 was reduced by approximately 40% during 3-OHB infusion in both groups compared with NaCl (participants with type 1 diabetes: median ratio 0.6; 95% CI 0.44, 0.82; p=0.003; control participants: median ratio 0.61; 95% CI 0.44, 0.84; p=0.004) (Fig. 6b). Here, LIPE is linked to type 1 diabetes mellitus.