Findings from the literature supported the direction of effect between BMI and circulating proteins for various effects identified in this analysis (CRP, Factor B and H, the interleukin 1 family of proteins, SAA/2, fibrinogen and antithrombin III), although for others there was no clear prior evidence suggesting that obesity influences their levels (Supplementary Table 8). Here, SERPINC1 is linked to obesity due to melanocortin 4 receptor deficiency.