L carnitine Supplement Benefits, Weight Control, Amino Acids, Fat Metabolism Tasman Health New Zealand A carnitine transporter at the bloodbrain barrier modulates sleep via glial lipid metabolism in Drosophila PNAS Carnitine Wikipedia L carnitine helps transport fatty acids into your cells' mitochondria, where they can be used for energy. That's why it's often marketed for fat loss and energy support. Common use: People usually take Fatty acid transportation mechanism in cell, starting with the activation of fatty acid by carnitine palmitoyl transferase 1 to acyl coA, which now attaches itself with the translocase to be transported across