Moreover, declined NAD+ levels have been associated with aging, obesity, and type 2 diabetes,[33] and supplementing NAD precursor shows improvements in energy metabolism, diurnal rhythm, and glucose metabolism in obesity and aging.[34] These facts not only provide an explanation of the increased PPARγ acetylation in metabolic disturbances of aging, obesity, and shiftwork but also raise the possibility of harnessing PPARγ acetylation via manipulating NAD+ levels to tackle metabolic dysfunctions. Here, PPARG is linked to obesity due to melanocortin 4 receptor deficiency.