NAD+ and NMN are sold for the same promise — raising the body's level of a coenzyme that falls with age — and the search volume for "NAD vs NMN" reflects a buyer choosing between a drip and a capsule. Neither is a peptide; both are sold through the same channels as research peptides, which is why they are catalogued here. This page lays the two records side by side. It does not pick one.
What each molecule is
| NAD+ | NMN | |
|---|---|---|
| Full name | Nicotinamide adenine dinucleotide | Nicotinamide mononucleotide |
| Formula / molecular weight | C21H27N7O14P2 / 663.4 | C11H15N2O8P / 334.2 |
| Role | The coenzyme itself: carries electrons in energy metabolism, and is consumed by repair and signalling enzymes (sirtuins, PARPs) | A precursor, converted to NAD+ inside cells in one enzymatic step |
| How it is sold | Intravenous drips, intramuscular and subcutaneous injections | Capsules, powders and sublingual tablets |
| US regulatory status | No FDA-approved injectable label; compounded or sold as a research product | Dietary supplement (FDA response letter posted 29 September 2025) |
The size difference matters. NAD+ is a large, charged molecule, and the one published infusion study found infused NAD+ was "rapidly and completely removed from the plasma" before levels rose — the detail is on our NAD+ dosage page. NMN is about half its size and is taken by mouth, which is why the two products end up on different routes.
The human trial records, side by side
NMN — oral, small, short. ClinicalTrials.gov listed 32 studies with nicotinamide mononucleotide as an intervention on 30 September 2026, only one with posted results. The trials cited most often:
- Yoshino et al., Science 2021 (NCT03151239): 25 postmenopausal women with prediabetes and overweight, 13 on NMN 250 mg a day and 12 on placebo, 10 weeks. Muscle insulin sensitivity and insulin signalling rose on NMN and not on placebo. Two authors hold NMN-related patent interests, disclosed in the paper.
- Yi et al., GeroScience 2023 (NCT04823260): 80 healthy middle-aged adults, placebo or 300, 600 or 900 mg a day, 60 days. Blood NAD rose in every NMN group; walking distance on a six-minute test improved; insulin resistance did not change; "no safety issues" were found. The lead author was employed by an NMN manufacturer.
- Christen et al., Nature Metabolism 2026 (NCT05517122): 65 adults, 14 days, comparing NMN, nicotinamide riboside and nicotinamide. NMN and nicotinamide riboside raised circulating NAD+ comparably; nicotinamide did not. The authors, from Nestlé Research, propose that gut bacteria convert NMN and nicotinamide riboside to nicotinic acid, which then drives the rise — meaning the capsule may work partly by a route other than intact NMN entering cells.
NAD+ — injected, fewer and more varied. The human injection record runs from 5 mg to roughly 700 mg per session, in a handful of studies:
- Yu et al., American Journal of Cardiovascular Drugs 2026: 180 adults with heart failure from ischaemic cardiomyopathy, NAD+ 10 mg intravenously once a day for 7 days, or placebo, alongside standard treatment. Ejection fraction at one month was 45.44% against 42.44% (p = 0.024); hospitalisation and symptom-class differences were not statistically significant. This is the largest randomized placebo-controlled NAD+ injection trial we have located.
- The wellness doses are on another scale. A US trial registration and a research vendor's vial both use 500 mg, fifty times the heart-failure trial's daily dose; our NAD+ dosage page traces the fifty-fold gap between the trial and clinic doses.
The two have never been compared in a trial. We found no registered or published study that randomised people to injected NAD+ versus oral NMN. Any "which is better" answer is an inference across different routes, doses, populations and outcomes.
Side effects, as recorded
- Injected NAD+. A 2026 retrospective review of a wellness clinic's records found every client given 500 mg intravenously on four consecutive days reported cramping, nausea or other symptoms, and infusions were slowed as a result. FDA's January 2026 warning letter to a compounding facility records three patients sent to the emergency room with low blood pressure and uncontrollable shaking after NAD+ from one lot that contained bacterial endotoxins. The full record, with FAERS counts, is on our NAD+ injection side-effects page.
- Oral NMN. The published trials, at up to 900 mg a day for up to about three months, report no safety signal. They are small, short, in healthy or prediabetic adults, and several are funded or staffed by manufacturers. FDA's adverse-event database held 8 reports naming "NMN" and 5 naming "nicotinamide mononucleotide" on 30 September 2026 — low numbers that reflect how rarely supplement users report, not measured safety.
Where the records do not reach
- Any head-to-head comparison of NAD+ and NMN.
- Whether raising blood NAD+ by either route changes any hard health outcome in people.
- Long-term use: no NMN trial we found ran beyond about three months; no NAD+ injection trial beyond weeks.
- Whether a given NMN capsule contains what its label says — supplement makers are not required to prove content to FDA before sale — or a given NAD+ vial is sterile and endotoxin-free, which the GenoGenix letter shows cannot be assumed.
Anyone weighing either for a medical reason should bring the specific product and this record to a doctor. The related compound often stacked with both, glutathione, has its own dosage page.
Sources and dates
- PubChem CID 14180 (NMN) and CID 5892 (NAD+), computed properties, read 2026-09-30.
- Regulations.gov docket FDA-2023-P-0872, document FDA-2023-P-0872-2754, "Response Letter from FDA HFP to Natural Products Association and Alliance for Natural Health USA", posted 2025-09-29 (document record read through the regulations.gov API 2026-09-30; the letter's PDF was not retrievable from here, and its conclusion is as summarised by the petitioner, Natural Products Association, in its release of the same date).
- Yoshino M et al. Science 2021;372(6547):1224-1229 (PMID 33888596; full text PMC8550608, methods read; registry NCT03151239).
- Yi L et al. GeroScience 2023;45(1):29-43 (PMID 36482258; NCT04823260).
- Christen S et al. Nat Metab 2026;8(1):62-73 (PMID 41540253; NCT05517122).
- Yu X et al. Am J Cardiovasc Drugs 2026;26(1):97-106 (PMID 40954388).
- ClinicalTrials.gov v2 API, intervention "nicotinamide mononucleotide": 32 studies, 1 with results (NCT04571008), 2026-09-30. openFDA drug adverse-event endpoint, medicinal product "NMN" (8) and "NICOTINAMIDE MONONUCLEOTIDE" (5), 2026-09-30.
- Our NAD+ dosage page (read 2026-09-17 sources) and NAD+ injection side-effects page (FAERS count 2026-09-25) for the NAD+ injection figures carried here.
Corrections go to the contact page.