L Carnitine: Benefits, Uses, Side Effects, and More 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. Private Label Infertility & PCOS Support Tablets L Carnitine has become one of the most commonly asked about supplements over the past 18 months and I can see why when looking at all the research that has come out about it over the last 2ish years.,