L Carnitine has a range of benefits for women with PCOS but, a new study set out to look at carnitine's impact on some of PCOS key indicators. One of those benefits reported 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., 12 Best PCOS Supplements for Hormone Balance, Fertility & Symptom Relief Mira Fertility Shop A Functional Medicine Approach to PCOS 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.