Apart from weight loss, are there any other health benefits or potential side-effects in supplementing with L-carnitine?

There has been a number of studies that suggest other benefits of supplementing with L-carnitine. In an Italian study, researchers reported a decrease in post-exercise plasma lactate and an increase in work output in subjects taking l-carnitine

 

Giamberardino has demonstrated the ability of L-carnitine to significantly reduce pain associated with eccentric exercise. In a six month study, researchers reported a significant reduction in blood cholesterol following supplementation with L-carnitine while Kobayashi has reported that administration of L-carnitine increased cardiac output and alleviated symptoms of CHD.