carlson labs acetyle l carnitine Metabolic Maintenance® Acetyl L-Carnitine Carlson - Acetyl L-Carnitine, 500

There are also several risk assessment about safety of carnitine

PLoS ONE

Carnitine, Healthy Weight Management, and Athletic Performance Carnitine has been a supplement of interest to athletes for some time, associated with the preservation of lean body mass, increased skeletal muscle, increased fat burning, and enhanced exercise performance and muscle recovery

FIGURE 5 The E2 subunit is encoded by dihydrolipoamide branched-chain transacyclase gene (DBT) and is the subunit to which E1 and E3 subunits are attached at the center of the complex

Carnipure is the most studied form of L-Carnitine, over two decades of research endorsed it as safe, pure and effective