Of 446 analysed Olink plasma proteins, 34 were identified as key components in the metabolic network, including CTRC, PON3, KITLG, APOM, CD4, LDLR, MFGE8, LPL, MATN2, FAM3C, FGF21, TGM2, IGFBP1, LEP, AGRP, ANXA4, ACE2, HMOX1, CHL1, MSMB, NRP1, FST, GUSB, GHRL, ANGPTL4, IGFBP2, CDH5, CTSD, SRCRB4D, FCRL5, WFIKKN2, CD300LG, ALDH1A1, and GH1, with 27 present in the non-diabetes network and 18 in the diabetes network, of which 11 were shared across networks. This evidence concerns the gene FGF21 and diabetes mellitus.