If you suspect mitochondrial damage, then d-ribose, acetyl carnitine, CoQ-10 and biotin are your supplements.

All of these are more expensive than the B12 and thiamine (benfotiamine), and omega-3's, and other vitamins.

Dr. Wahl's diet includes large amounts of colorful vegetables with antioxidant properties as well. She leans heavily on sulfurous veggies like broccoli and kale, also.

Anyone who suspects mito damage will have to stop using drugs that damage them, like the fluoroquinolones, and statins.(and other less common ones). Stop smoking also which affects blood circulation to the periphery, and which contains many toxins in the smoke as well.

Dr. Bruce Ames made his supplement Juvenon, for this express purpose. He believes also that faulty B-complex metabolism in the cells is also a cause of mito decay. If you search him, you'll find his website which has alot of detailed information on it.