L Carnitine vs Acetyl L Carnitine: Key Differences Acetyl L Carnitine VS L Carnitine: Which is Better? Acetyl L Carnitine is more thought of as a fat burner. It's actually powerful tool for athletes looking to improve endurance, energy, and mental performance. Here's how you can integrate it into your routine for Acetyl L Carnitine 500mg Cognitive Support Carlson Momentous Acetyl L Carnitine 60 Servings L Carnitine Linus Pauling Institute Oregon State University