Injectable L Carnitine How It Works & What to Expect? Acetyl L Carnitine Study NOW Foods L Carnitine Arazo Nutrition The Role of l Carnitine in Mitochondria, Prevention of Metabolic Inflexibility and Disease Initiation L carnitine supplements bioavailability is very less and according to some studies it takes 8 to 12 weeks for for loss results, so if you decide to supplement with oral L carnitine do take it in