The tree · Energy and fuel sensing
A supplement that raises a cell's NAD improves an age-related function in a controlled trial
NAD is a molecule every cell uses to turn food into energy and to run its repair enzymes, and its level in tissues falls with age. Two building blocks of it, nicotinamide riboside and nicotinamide mononucleotide (NMN), are sold as supplements on the strength of mouse studies in which they restored muscle and blood vessels in old animals. In people, both raise NAD in the blood; the first controlled result on a function came in 2021, when a St Louis group found that ten weeks of NMN improved how well muscle responded to insulin in overweight women past the menopause, though it did not change their weight, blood sugar or fitness. Larger trials have been mixed, and no regulator has approved either for anything.
What would count
A controlled trial in people reports that a compound given to raise NAD improves an age-related function (muscle, blood vessels, insulin response, walking) more than placebo on the trial's pre-stated main measure, in a peer-reviewed report. The animal rung is the same in a living animal. For the clinic rung: a regulator approves such a compound as a treatment for an age-related condition; sale as a supplement does not count.
Who settles it: The peer-reviewed trial report; the regulator's approval record for the clinic rung.
Where it stands
First human. Reached 22 April 2021, on the record of Yoshino and 10 others, 22 April 2021 (doi.org). Next rung within 5 to 20 years.
When it reaches the clinic: the project's estimate
This is the one thing on this page that is a judgment rather than a record. The project's estimate of the year it reaches the clinic is 2042, no earlier than 2032 and no later than 2090; the model draws from that range every run, with the likely year the most probable draw. Set 16 October 2026, a first pass awaiting an outside review.
| Rung | No earlier than | Most likely | No later than | |
|---|---|---|---|---|
| In clinical use | 2032 | 2042 | 2090 | feeds the year at the top |
Why. No company was carrying an NAD precursor through drug trials for an age-related condition when this was written, because the compounds cannot be patented; the likely year assumes an academic trial in muscle or heart failure reports positive in the early 2030s and a drug-grade version is approved in the early 2040s. The earliest assumes a drug company's related compound reaches an approval sooner; the latest allows for the mixed trials being the true answer.
Changes to this record
None since it was written on 16 October 2026. Every change to the stage or the estimate lands here with its date, the old value, the new one and the reason, and a change to the estimate never happens because a number looked wrong: it needs a dated reason and a source.
The last readings
- 17 October 2026 Quiet
Nothing in the window: no peer-reviewed controlled trial of an NAD-raising compound on an age-related function dated 2026-10-10 to 2026-10-17 was found, and no regulator's approval. Older items seen and falling short: a December 2025 pilot of nicotinamide riboside in 52 people with mild cognitive impairment (NAD rose, cognition did not improve); a ClinicalTrials.gov entry (NCT04571008, Effect of NMN Supplementation on Organ System Biology) showing results first posted 2026-03-11 and last updated 2026-08-17, which is a registry posting and not a peer-reviewed report, and whose findings were not visible; and a 2026 company document describing a 66-person trial of nicotinamide riboside with exercise in Friedreich's ataxia, an inherited disease rather than an age-related function. None of these moves the leaf, which is already at first human and whose next rung is a regulator's approval.source 1, source 2, source 3
What the story so far says about it
On the record
- 22 April 2021Nicotinamide mononucleotide increases muscle insulin sensitivity in prediabetic women
- 29 March 2018Chronic nicotinamide riboside supplementation is well-tolerated and elevates NAD+ in healthy middle-aged and older adults
Notes
These compounds are the most-sold "anti-ageing" supplements, which is why the leaf's clinic rung is written to exclude supplement sales: millions of people taking something is not the same as a regulator having looked at whether it works. The 2021 result is small and in one function; the leaf stays at first human until a larger trial.