L Carnitine for weight loss is and heres why. There is zero published scientific data to support that L Carnitine actually helps you lose body fat. I went ahead and purchased the meta analysis Carnitine: the claims and why it may not work L carnitine for metabolism Lifehack 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