ALCAR, a better utilized form of Carnitine, has been well researched, and numerous studies have connected it to longevity benefits. It is inexpensive, so it would be an obvious one to take if the benefits are true.
It is often described as "reducing the effects of glycation" and having benefits to the brain in particular.* This is accomplished through its role of transporting fatty acids across the cell membrane, and those are important for the mitochondria.
Studies have shown that it improves energy levels and muscle strength, and protects against some neurotoxic insults.
Our own research has pointed to not taking the high amount commonly recommended, which is sometimes as high as 1000 mg per day or higher.
The proper amount of ALCAR to take may depend on the amount of fatty acids available in your body. If more are available, a higher amount of ALCAR might easily be too much. More research is needed.
The study referenced earlier found that chronic use of ALCAR decreased glucose metabolism to lactate, and reduced GABA in the hippocampal formation of the brain.