Polycystic Ovary Syndrome (PCOS): Symptoms & Nutritional Strategies. Life Extension L Carnitine: Benefits, Side Effects, FAQ, Sources, and Dosage L Carnitine Linus Pauling Institute Oregon State University 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. PCOS Nutrition Center L Carnitine (120 Capsules) Co administration of Spirulina and L carnitine preserves ovarian reserve in a rat model of premature ovarian insufficiency via SIRT1 regulation of oxidative stress, inflammation, and apoptosis Scientific Reports