This guy isn't talking about something simple. The biomarker he's looking forward is just as elusive as the biomarker for ME/CFS. He's talking about nutrient depletion, persistent infections, autoimmunity, mast cells, compromised energy production. This has all been going on in ME/CFS and there aren't any neat answers, certainly not just taking NAD+ - yes, it's a help, but it doesn't fix the underlying problem.