I like to base supplement protocols off of data. That is why I test before recommending things because everyone will have different bottlenecks in their metabolism.

Some key nutrients are magnesium, copper, B1, B2, B3, B5, ALA, CoQ10 etc...

Metabolomix+ testing allows me to see where the functional deficiencies are. Also highlights heavy metals toxicities that can impair the enzymes shown above.