Health Reference LibraryNADH: the coenzyme form of B3 and what the trial doses actually were
This entry is part of the Nutri Tailor Health Reference Library — cited research on supplements, nutrients and adjacent areas of health.
Summary
NADH is the working coenzyme of vitamin B3 in its reduced form, the direct electron donor feeding the mitochondrial respiratory chain where ATP is generated, and NADH needs no conversion before participating in energy metabolism, unlike niacin or niacinamide. The fatigue research used specific doses. The 1999 crossover trial in chronic fatigue syndrome used a stabilised 10mg daily dose, with 31 percent of patients responding against 8 percent on placebo, and a larger 2021 trial paired 20mg of NADH with CoQ10. This capsule provides 1mg, a tenth to a twentieth of those studied doses, so the honest use is gentle coenzyme support, and a trial-scale routine needs several capsules, where niacinamide may serve the NAD+ goal more economically.
How it works
NADH is the reduced, electron-carrying state of NAD, the coenzyme built from vitamin B3. In mitochondria, NADH hands electrons to complex I of the respiratory chain, the first step of the sequence that generates ATP, and NADH also participates in neurotransmitter synthesis pathways for dopamine, noradrenaline and serotonin. Swallowed NADH faces an acidic stomach and enzymatic degradation, which is why trial products used stabilised formulations, and why part of any oral dose likely arrives as its breakdown products feeding the same NAD pool that niacinamide feeds.
Effective dose
The clinical research doses are specific. Forsyth and colleagues used 10mg of stabilised oral NADH daily in the 1999 chronic fatigue crossover trial, and Castro-Marrero and colleagues used 20mg daily alongside 200mg CoQ10 in the 2021 trial of 207 patients. This capsule provides 1mg of NADH, so reaching trial-scale intake means ten or more capsules, which is neither the design nor an economical route. One to two capsules daily is gentle coenzyme support; anyone specifically pursuing the researched fatigue protocols should look at dose arithmetic first and discuss persistent fatigue with a GP regardless.
Forms compared
Each capsule provides 1mg of NADH in a vegetarian capsule shell, made in the UK, with NADH as the sole active ingredient. NADH is inherently unstable in light, heat and acid, so keep the pot closed, cool and dry. Niacinamide is the robust, inexpensive precursor route to the same NAD pool at hundreds of times the milligram dose, which is the honest comparison anyone considering NADH should see.
Timing
Trial protocols dosed NADH in the morning on an empty stomach with water, on the reasoning that food and stomach acid conditions affect survival of the molecule. Taking NADH first thing before breakfast mirrors the researched pattern. Consistency matters more than perfection, and nothing about NADH requires evening avoidance, though some users prefer mornings given the energy framing.
Safety profile
The trials reported no severe adverse effects related to NADH at 10 to 20mg daily, and 1mg daily sits far below those doses. NADH does not cause the flushing associated with nicotinic acid. Persistent, unexplained fatigue deserves a GP review before any supplement, because anaemia, thyroid conditions, sleep disorders and low B12 or vitamin D are common, testable causes, and a supplement that soothes the symptom can delay finding the driver.
Special populations
People with diagnosed ME or chronic fatigue syndrome considering the researched protocols should involve their GP or specialist, both for dose-scale honesty and because the condition's care benefits from coordination. Pregnancy and breastfeeding lack NADH-specific safety data, so a standard B3 intake through diet or prenatal products is the default there. Anyone with ongoing fatigue plus weight change, breathlessness, low mood or pain has a GP-shaped picture, not a supplement-shaped picture.
Interactions
NADH has no well-documented drug interactions at supplemental doses, which partly reflects limited study rather than proven neutrality. The theoretical overlap with blood-pressure medication through vasodilation belongs to nicotinic acid, not NADH. Nutri365 checks for interactions and contraindications across the whole supplement and lifestyle picture when you use the platform.
Guideline positions
Forsyth and colleagues (Annals of Allergy, Asthma and Immunology, 1999) ran a randomised, double-blind, placebo-controlled crossover of 10mg stabilised oral NADH in 26 chronic fatigue syndrome patients, with 31 percent responding on NADH against 8 percent on placebo and no severe adverse effects, framed by the authors as a pilot needing larger trials. Castro-Marrero and colleagues (Nutrients, 2021) randomised 207 ME and chronic fatigue patients to 20mg NADH plus 200mg CoQ10 or placebo for 12 weeks, reporting reduced cognitive fatigue perception and quality-of-life gains. No UK guideline recommends NADH for any indication.
Practical framework
Choose NADH when you want the pre-formed coenzyme itself in small amounts as part of an energy-support routine, with eyes open that the fatigue research used 10 to 20mg daily. Niacin (NADH) provides 1mg per capsule at £20.44 for the bottle, in stock and UK-made, at nutritailor.co.uk/products/niacin-nadh. Take in the morning before food, mirroring the trial pattern. For NAD+ repletion at meaningful milligram scale, the niacinamide entry sets out the economical precursor route, and persistent fatigue belongs with a GP first.
Common misconceptions
NADH marketing often implies any dose delivers the trial results, when the researched doses were 10 to 20mg of stabilised formulations and this capsule is 1mg. A second misconception is that swallowed NADH arrives intact at mitochondria, when stomach acid and gut enzymes degrade much of an oral dose toward the same precursor pool niacinamide feeds. Third, NADH is sometimes confused with nicotinic acid; NADH neither flushes nor modifies lipids.
Sources
- Forsyth LM, Preuss HG, MacDowell AL, Chiazze L Jr, Birkmayer GD, Bellanti JA 1999. Therapeutic effects of oral NADH on the symptoms of patients with chronic fatigue syndrome. Ann Allergy Asthma Immunol 82:185-91.
- Castro-Marrero J et al 2021. Effect of Dietary Coenzyme Q10 Plus NADH Supplementation on Fatigue Perception and Health-Related Quality of Life in ME/CFS. Nutrients 13:2658.
- Council for Responsible Nutrition 2025. Vitamin B3, in Vitamin and Mineral Safety 4th Edition. CRN.