BSN say that L-Carnitine is for fat loss, recovery, and support. Unfortunately it is ineffectual for all three (whatever the third means) in all but the elderly. Even then the effect is minor.
I first decided to supplement with L-Carnitine after hearing of its fat loss attributes. However as I found out from the experience, and research (which I had unfortunately done AFTER purchasing) - it was a waste of money. It is not OVERLY expensive, but for what it does even $1 would be too much.
Some people say they take it when they cut, and it is added to many protein mixes that advertise it as a fat burning compound, but make no mistake: any fat loss results you get will be because of diet and exercise.