A systematic review by Sindhughosa et al. [50] showed that vitamin D supplementation significantly improved insulin resistance, with a reduction in HOMA-IR levels (MD: −1.06; p = 0.0006), increased vitamin D levels by 17.45 ng/mL (p = 0.0002), and modestly reduced ALT levels (MD: −4.44; p = 0.02). The gene discussed is GPT; the disease is Insulin resistance.