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., L carnitine improves polycystic ovary syndrome by increasing CYP11A1, estrogen receptor, and decreasing XNIP and VEGF expression Naunyn Schmiedeberg's Archives of Pharmacology Springer Nature Link How L Carnitine Supports Insulin Resistance Management Oana Posts L carnitine is a naturally occurring amino acid structure that is made in the human brain, liver, and kidneys. L carnitine plays a critical role in energy production, as it converts fat into energy. Best PCOS Supplement Combos: Boost Your Health & Goals