Combined with the conclusion of Maeda (Maeda et al., 2005) that the lack of both FABP4 and FABP5 has a stronger protective effect on diet-induced insulin resistance, obesity, and atherosclerosis than any single lack, so we speculated that silibinin may also affect lipid transport through FABP5. Here, FABP4 is linked to obesity due to melanocortin 4 receptor deficiency.