In corroboration with epidemiological studies demonstrating the association between PBDE exposure and obesity, as well as the accumulation of PBDE in adipose tissue, laboratory data indicate that adipogenic effect of PBDE is mediated by the up-regulation of PPARγ and C/EBPα signaling (Figure 1) through a variety of mechanisms including epigenetic effects, modulation of oxidative stress, adipose tissue inflammation, thyroid functioning, and gut microbiota. This evidence concerns the gene PPARG and obesity due to melanocortin 4 receptor deficiency.