Hormones and metabolites from study 1 comprising overweight healthy men. (A) Plasma GLP-1 increased during acipimox treatment. (B) Acipimox did not affect plasma GIP levels. (C) Plasma glucose increased to a lesser extent after the OGTT during acipimox treatment. (D) Serum FFAs were suppressed more after the OGTT during acipimox treatment. (E) Acipimox did not affect serum insulin levels. (F) The change in AUCs (delta FFA, control minus cipimox; delta GLP-1, acipimox minus control) between acipimox treatment and the control experiment in FFA and GLP-1 were compared and revealed a significant correlation. Printed P values refer to comparison of AUCs. Asterisk indicates significant differences in a pairwise comparison. All data are presented as mean ± SEM. Acipimox, white circles; control, black triangles.