Does L Carnitine have side effects? (L Carnitine) L Carnitine Linus Pauling Institute Oregon State University L Carnitine: Uses, Benefits, Dosage, and Side Effects StrengthLog Understanding the Benefits and Uses of Carnitine in Health and Fitness Fitness Health Early research into L carnitine was often cited as underwhelming, showing negligible changes in muscle carnitine content and fat loss outcomes. However, these findings may have been limited by a short study window