NAD+

Coenzyme (not a peptide) · B-tier (Dr. Alex Tatem) · Limited evidence

A coenzyme essential to cellular energy. Levels fall with age, so topping them up makes sense on paper. Proof of benefit from IV or injected NAD+ is thin.

Dr. Tatem’s take

B-tier: “as safe as any other compound that we’ve ever talked about”, with sound biology, though it “may not have a ton of placebo-controlled peer-reviewed data.”

In Dr. Tatem’s tier list

• Not a peptide — a coenzyme essential for redox reactions and handling oxidative stress. Once niche, now everywhere, often as IV infusions.
• Most supporting data comes from tissue and lab studies rather than clinical trials, but the mechanism is sound.
• It is “as safe as any other compound that we’ve ever talked about” and has been used in thousands of people with very good safety.
• Verdict: B tier, even without much placebo-controlled peer-reviewed data.

History & background

NAD (nicotinamide adenine dinucleotide) was discovered in 1906 by Arthur Harden and William Young as a “cozymase” needed for yeast fermentation; Harden and Hans von Euler-Chelpin shared the 1929 Nobel Prize in Chemistry partly for this work.

Interest in NAD+ for aging grew in the 2000s–2010s after research linked falling NAD+ levels to aging in animals, which fueled oral precursors (NR, NMN) and IV “drip” clinics. No IV NAD+ product is FDA-approved.

Benefits

• Central to cellular energy metabolism and DNA repair.
• Oral precursors (like NR) raise NAD+ levels in small trials.

Risks

• Fast IV infusions cause nausea, cramping, chest tightness and flushing.
• Long-term effects unknown.

Dosing protocols (informational, labeled by evidence)

• Clinical trial / label: IV pilot study — ~750 mg (3 µmol/min for 6 h), IV infusion, Single, Single
• Physician / clinic: Wellness-clinic IV — 250–1000 mg per infusion, IV, slow drip over hours, Loading series, then periodic, Varies
• Community (bro science): Community subQ — ~50–100 mg, SubQ, Daily to a few times/week, Varies

Status: Not an FDA-approved drug for any use. IV infusions over 100 mL per 12 hours are banned in tested sport.

Grade and commentary: Dr. Alex Tatem. Watch: Truth About More Popular Peptides (What Works, What’s Overhyped) | Peptide Tier List pt.2, The Truth About NAD (From a Doctor). Subscribe: @DrAlexTatem.