Digestion Muscle Specific Deletion of Carnitine Acetyltransferase Compromises Glucose Tolerance and Metabolic Flexibility ScienceDirect PDF) Effects of oral L carnitine supplementation on insulin sensitivity indices in response to glucose feeding in lean and overweight obese males There's a reason L carnitine keeps showing up in PCOS research Because PCOS is closely tied to insulin resistance, inflammation, and metabolic dysfunctionand L carnitine plays a role in energy metabolism and fat utilization.