NADH (Coenzyme 1)

Tier 3 — weak evidence · Energy · Chronic fatigue · Cognition

The reduced form of NAD+ that plays a central role in cellular energy production. A few small trials suggest benefit for chronic fatigue syndrome, with one showing significantly improved fatigue scores versus placebo. Also studied for jet lag recovery. The sublingual form absorbs better than oral tablets. Evidence base is very limited and mostly from small, older studies. Expensive relative to the strength of evidence.

Dose: 5–10 mg/day sublingual on an empty stomach; limited evidence beyond chronic fatigue syndrome