NAD+

Mechanism

NAD+ (nicotinamide adenine dinucleotide) is a coenzyme involved in hundreds of metabolic reactions, particularly the redox reactions that drive ATP production and the sirtuin enzyme family that's been studied in aging research. Cellular NAD+ levels decline measurably with age, which has motivated interest in supplementation as a longevity-protocol target.

NAD+ itself is a large, polar molecule with poor membrane permeability. Most research-protocol NAD+ administration is subcutaneous or IV because oral bioavailability is low. Precursors like NMN and NR are common alternatives because they cross membranes more efficiently and convert to NAD+ intracellularly.

Research dosing

The published research-protocol literature spans a wide range. Common reference doses:

• 100–250 mg subcutaneous as a maintenance protocol
• 500 mg IV as an intensive single-dose research administration
• NMN / NR oral analogs typically dosed in the 250–1000 mg range

Half-life is short — NAD+ is rapidly partitioned across compartments and converted to downstream metabolites. The clinical question of whether boosting circulating NAD+ produces meaningful increases in tissue NAD+ levels is still being characterized in human trials.

Side-effect profile in research

Most-reported research-protocol observations are administration-route specific. Subcutaneous NAD+ commonly produces flushing and a transient burning sensation at the injection site — this is mechanistically expected and generally resolves within minutes. IV administration at high doses can produce nausea and chest tightness if infused too quickly; protocols specify slow infusion rates accordingly.

What we cover

Vendor audits for NAD+ focus on:

• Identity confirmation — NAD+ is sometimes shipped as the precursor (NMN or NR) labeled as NAD+. Mass-spec identity confirmation is essential.
• Purity — NAD+ degrades during storage and shipping if not properly handled. Lower-purity batches often reflect storage problems rather than synthesis problems.
• Bacteriostatic water reconstitution — NAD+ is unstable in solution. Some research protocols specify sodium chloride 0.9% rather than bacteriostatic water; vendor packaging instructions vary.