NAD+ drops by roughly half by middle age. Four questions tell you who can prove a refill.

Every company selling an NAD+ supplement opens with the same sentence, and the sentence is true. Nicotinamide adenine dinucleotide sits in every cell you own. It carries electrons through the reactions that turn food into usable energy, and it is the co-substrate that a family of repair proteins called sirtuins cannot work without. Levels fall as you get older. By middle age the drop is around 50 percent.

That much is free. Any brand can say it, and most of them do, because nobody is ever asked to prove it. The expensive sentence is the second one: the claim that a capsule puts some of it back.

Almost nothing separates NAD+ products at the level of the first sentence. Everything separates them at the level of the second. What follows is a four question audit you can run on any bottle in the category, in the order that matters, together with what happens when you run it on Basis, the product Elysium Health has been selling since 2015.

What the molecule actually does, in two jobs

NAD+ runs two separate lines of work, and Elysium splits them the same way in its own explainer. The first is metabolic. NAD+ accepts and donates electrons in the chain that converts nutrients into cellular energy. Nothing about that job is negotiable. The second is regulatory. NAD+ is required by sirtuins, the proteins that supervise cellular housekeeping. Sirtuins can only function in the presence of NAD+, as the company puts it. When NAD+ falls, sirtuin activity falls with it.

That is why the molecule became a target rather than a curiosity. You cannot simply swallow NAD+ and expect it to arrive intact. What you can swallow is a precursor, a smaller molecule your cells convert. Basis uses nicotinamide riboside, a naturally occurring form of vitamin B3, which the body turns into NAD+ in a two step process. It pairs that with pterostilbene, a polyphenol found in blueberries and a more potent relative of resveratrol, aimed at the sirtuin side of the ledger.

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Question oneWas it ever tested in a person?

Most of what gets written about NAD+ comes from cells in a dish and from mice. That work is real, and it is also the cheapest kind of evidence to point at, because a molecule that lights up a petri dish has cleared none of the obstacles between a lab bench and your bloodstream. The first question is therefore blunt. Did anyone give this to human beings and measure what happened.

Elysium did, and it was the first trial of its kind for nicotinamide riboside: the first repeat dose study, and the first test of NR combined with pterostilbene in people.

Question twoWas there a placebo group, and was anybody blinded?

An uncontrolled study of a supplement will almost always produce a happy number, because the people who enroll want it to work and the people running it want it to work too. Randomization and blinding exist to take that wanting out of the result. Elysium's trial was double blind, randomized and placebo controlled, with three arms rather than two.

The reported outcome: participants on the recommended dose saw cellular NAD+ rise by an average of 40 percent over baseline at 30 days, and that level held at 60 days. Participants on double the recommended dose rose 90 percent at 30 days, then settled back to 55 percent at 60. The placebo group had no increase at all. No serious adverse events were reported.

Question threeCan you read the paper yourself?

A trial that exists only as a sentence on a product page is a claim, not evidence. The version that counts is the one a reviewer outside the company saw, with the methods attached, in a journal you can open. Elysium's first study was published in November 2017 in a peer reviewed Nature partner journal, open access, and the company states plainly that publishing in open access peer reviewed journals is a policy rather than an accident.

You do not have to be a biochemist to get value out of a citation like that. The author list tells you the chief scientist and the chief executive both put their names on the result, which means neither can quietly disown it later. The journal name tells you a third party reviewed the methods. The date tells you the claim has been standing in public, available to be attacked, for the better part of a decade.

Question fourIs the dose in the bottle the dose in the study?

This is where most claims in the category quietly come apart, and it is the easiest of the four to check. A brand cites a trial. The trial used a specific quantity of a specific compound. The product contains something less, or something adjacent, or a proprietary blend that refuses to say. The citation stays on the page. The dose does not match it.

The recommended arm of the Basis trial took 250 mg of nicotinamide riboside and 50 mg of pterostilbene. The supplement facts panel on the pouch reads Elysium NR 250 mg and PT 50 mg per serving, a serving being the two capsules you take in the morning. Two numbers, one panel, thirty seconds of your time.

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What happened when one of the answers came back no

A company that only ever publishes the studies that worked has told you nothing at all, because you have no way to know how many did not. So the most informative item on Elysium's science page is not one of its wins.

That is a negative result about their own molecule, kept in public view, next to a buy button. It is the single strongest thing on the page, and it is strongest precisely because it is unflattering.

Seventeen registrations, and who is holding the clipboard

The other reason to look past the marketing copy is the registry. A trial listed on ClinicalTrials.gov has to declare, before it starts, what it will measure and when. That declaration is what makes it hard to run a study, dislike the answer and change the question afterwards. Elysium's science page carries seventeen of those identifiers.

Two of the completed studies were reported in journals with no stake in the outcome, one in Hepatology and one in Nature Aging. A separate toxicology study of the company's proprietary form of nicotinamide riboside appeared in the International Journal of Toxicology in 2020. Whatever you make of the conclusions, the pattern is a company that keeps handing its molecule to people who are free to say no.

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Who signs off, and what that signature covers

Basis was developed by Leonard Guarente, co-founder and chief scientist at Elysium, professor of biology at MIT and head of its aging center. He is one of the people who established that sirtuins matter to aging in the first place, which is the field this whole product category grew out of.

Behind him sits a scientific advisory board of more than 25 researchers and clinicians, eight of them Nobel laureates. The useful detail is in the small print of how it works. Elysium states that the board does not endorse a specific product. It advises on which compounds to pursue, how to design the studies and what the research says. That is a narrower claim than most brands would make with the same names, and it is the honest one.

• Carolyn BertozziStanford University
• Aaron CiechanoverTechnion, Israel
• Eric KandelColumbia University
• Martin KarplusHarvard University
• Paul ModrichDuke University
• Sir Richard RobertsNew England Biolabs
• Thomas SüdhofStanford University
• Jack SzostakUniversity of Chicago

The eight Nobel laureates named on elysiumhealth.com/pages/advisory-board, alongside more than seventeen other scientists and clinicians.

"The company boasts an impressive board of scientific advisors and presents results of its clinical trials." Business Insider, quoted on Elysium's news and media page

The part that has nothing to do with the paper

A trial validates a formula. It says nothing about the specific pouch a courier leaves at your door, and in a category with a long history of contamination and label inflation, that gap is not academic.

Basis is NSF Certified for Sport, which is the only independent third party certification program recognized by the United States Anti-Doping Agency. Certification is granted lot by lot, not once and forever, and Elysium publishes the certification status and the quality and purity information for every lot it ships. That means the number on the bottom of your pouch is checkable against a public record, by you, on a Tuesday, without asking anyone's permission.

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The honest ceiling on a 40 percent

Here is what the trial did not do. It measured NAD+ in whole blood. It did not measure how you feel on a Thursday, and no reading of it should promise that. Elysium says as much in its own FAQ: Basis is designed to work beneath the surface, and you may not feel different despite what the company believes is happening inside.

You can watch that play out in their own review section, which they have not scrubbed.

Leaving that on a product page is a choice. The alternative reading of the same evidence is the one you get from people who decided the mechanism was reason enough and stayed on it for a decade.

What long term customers actually say

Basis carries 1,293 published reviews at an average of 4.5 out of 5. What is unusual about the set is its tenure. A large share of the writers are not reporting on a first month. They are reporting on year seven, year ten, year twelve.

Sarah's second sentence is the whole problem of the category, stated better than most trial write-ups manage. Nobody has a control version of themselves. Which is exactly why the four questions above are worth the ten minutes: they are the only part of the decision that does not depend on how you happen to feel this week.

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The practical part

Run the four questions on anything else

The audit is not about one brand. It is a filter, and it works on any bottle in any aisle that leans on a mechanism to justify a price.