L Carnitine and Sleep: Does It Affect Rest or Sleep Quality? 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. Morning or Evening? Best Time to Take L Carnitine LABRADA INDIA 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 The Role of l Carnitine in Mitochondria, Prevention of Metabolic Inflexibility and Disease Initiation