The benefit with randomized human evidence behind it is narrow: NAD⁺ precursors raise the amount of NAD⁺ in your blood, reliably and dose-dependently. The benefits the category is actually marketed on — energy, focus, slower aging, recovery — have not been established in any format, and for injected or infused NAD⁺ they have not been tested at all.
One housekeeping note before the substance. NAD⁺ is not a peptide; it is a dinucleotide coenzyme, and it picks up the label because it is sold from the same menu as sermorelin and BPC-157. We unpack that in is NAD⁺ a peptide, and it matters here mainly because it means peptide research does not transfer: the NAD⁺ evidence base has to be judged on its own.
What the trials actually measured
Almost every well-run NAD⁺ trial has the same primary endpoint, and it is a blood level.
A randomized, multicenter, double-blind, placebo-controlled trial randomized 80 healthy middle-aged adults (n = 80) to placebo or 300, 600 or 900 mg of NMN daily for 60 days. Blood NAD concentrations rose significantly in every treated group at day 30 and day 60 against both placebo and baseline (all p ≤ 0.001) [1]. An eight-week randomized, placebo-controlled trial of nicotinamide riboside at 100, 300 and 1,000 mg raised whole blood NAD⁺ by 22%, 51% and 142% within two weeks [2].
Those are real results and they are the reason this category is not simply snake oil. They are also biomarker results. Raising a coenzyme you can measure in a tube is a precondition for a benefit, not the benefit itself.
What happened when someone measured an outcome
This is the part sellers do not quote. A placebo-controlled randomized pilot gave nicotinamide riboside to older adults with mild cognitive impairment, escalating to 1 g a day over a 10-week study. Blood NAD⁺ rose 2.6-fold in the NR group (p < 0.001, 95% CI 17.77 to 43.49), with no between-group difference in adverse events — and the cognitive measures, including the Montreal Cognitive Assessment, stayed stable throughout [3].
Read that as a pair. The drug did what it was supposed to do biochemically, by a wide margin, and the thing people buy it for did not move. That is the shape of this literature, and it repeats.
A systematic review published in early 2026 put a census behind the impression. Searching human and rodent intervention studies of NAD-related compounds from January 2010 to October 2025, it identified 113 eligible studies — 33 human intervention studies, 28 of them randomized — and concluded that oral NR and NMN consistently demonstrate biochemical target engagement and are generally well tolerated over weeks to months, while effects on functional, metabolic, vascular and other healthspan-relevant outcomes were heterogeneous and often null or endpoint-specific. It also reported that no eligible outcomes trial evaluated intravenous or intramuscular NAD⁺ itself for anti-aging or wellness indications [4].
The four claims you will see on a clinic page
“More energy.” The mechanism is real — NAD⁺ carries the electrons that end up as ATP — and the inference from mechanism to felt energy in a healthy person is not supported by a controlled trial. Mechanism is a hypothesis, not a result.
“Mental clarity.” The one trial that measured cognition properly found it unchanged while the biomarker moved 2.6-fold. That is the most relevant evidence anyone has, and it points the other way.
“Anti-aging.” No controlled outcome trial in any format. Most of what is cited for this claim is rodent work, and the gap between the mouse data and the human data is the whole subject of our benefits page.
“Addiction and recovery protocols.” Widely advertised by infusion clinics, usually at the top of the price list, with no controlled outcome trial we can find supporting the indication.
What this means for a course you are about to buy
Decide which of the two things you are paying for. If it is the measured biomarker, an oral precursor delivers it in randomized trials for a few dollars a week, and the supplement board is where those sit. If it is one of the outcomes, no format has shown it, and the expensive formats have shown it least.
That matters most on price. The one IV seller we have found that publishes a dose works out at about $3.20 a milligram, against roughly $0.15–$0.25 for the injection sellers that publish one — 13 to 21 times more for the same molecule, with less evidence behind the route, not more.
Before paying for any protocol, get the milligram figure and the number of sessions in writing. Without both, no comparison is possible, and the questions worth asking are short enough to take to a consultation.