INS and type 2 diabetes mellitus: Supplementation with vitC (500 mg/day) increased insulin sensitivity and the expression of the SVCT2 transporter in skeletal muscle in type 2 diabetic patients [121], supporting findings that an intake of high-dose ascorbic acid (above 1 mg/day) exerted a beneficial effect on maintaining blood sugar homeostasis and decreasing insulin resistance in type 2 diabetic patients [119].