HOMA-IR and fasting insulin were improved only in the overweight or obesity group (−3.84%, 95% CI: −6.11% to −1.57%, p = 0.009 for HOMA-IR; −2.36%, 95% CI: −4.52% to −0.19%, p = 0.042), while no effects on weight status was observed (p = 0.061 for HOMR-IR; p = 0.166 for fasting insulin). Here, INS is linked to obesity due to melanocortin 4 receptor deficiency.