NAD+ for men: what it can and cannot do

What is actually established

The biology is real, and it is worth separating from the marketing before anything else. NAD+ is a coenzyme your cells cannot function without. It carries electrons through the reactions that produce cellular energy, and it is consumed by enzymes involved in DNA repair signalling and metabolic regulation. Levels decline with age. None of that is controversial.

• Established. NAD+ is essential to cellular energy metabolism, and tissue levels fall as people get older.
• Demonstrated in humans. Oral precursors raise blood NAD+. Nicotinamide riboside did so in healthy middle-aged and older adults, nicotinamide mononucleotide did so in older men, and a head-to-head trial found both roughly doubled circulating NAD+ within two weeks.
• Reasonably established. Tolerability. Across the trials run so far, NAD+ and its precursors have been generally well tolerated, with the common complaints being rate-related flushing and nausea.
• Not established. That raising the number changes how you feel, perform, recover or age.

That last line is the whole argument of this page, and it is why the honest version of this product is worth more to you than the enthusiastic one.

What the trials say about the claims men see

The claims in this category are made mechanistically, then presented as outcomes. Here is the state of the human evidence for each of the ones aimed at men.

Does NAD+ raise testosterone?

There is no human trial showing that NAD+ or its precursors raise testosterone. This claim is everywhere in the men's wellness category, and it is worth knowing exactly where it comes from so you can recognise it.

The mechanism story goes like this. Testosterone is produced in the Leydig cells of the testes, that production is energy intensive and depends on mitochondrial function, and several enzymes involved in mitochondrial regulation depend on NAD+. Animal and cell studies have explored whether raising NAD+ availability supports that machinery, and some report effects in aged or metabolically stressed models. That is genuinely interesting biology.

It is also several steps away from a man's blood test result. A plausible pathway in mouse tissue is not a measured change in human serum testosterone, and the trials that would settle it have not been run. So the accurate statement is that this is mechanistic and animal-level only, with no human trial support, and that is the statement we are going to keep making while competitors round it up to a benefit.

If low testosterone is what you are actually worried about, the path is a morning blood test repeated on a second morning, not a supplement or an injection aimed at a different system. Start with what are the symptoms of low testosterone. Testosterone therapy at Expert Health is prescribed only for men whose hypogonadism is confirmed by lab testing.

Why men in midlife look at NAD+ at all

The pitch lands because the problem is real. Somewhere in the forties, a lot of men notice the same cluster: the training session that used to take a day to recover from now takes three, the afternoon slump that coffee no longer fixes, the sense of running at a lower baseline. NAD+ marketing maps neatly onto that, because cellular energy is a satisfying explanation for feeling flat.

The problem is that the same cluster is produced by sleep debt, undiagnosed sleep apnea, alcohol, thyroid disease, anemia, low mood and sometimes low testosterone, all of which are checkable and several of which are treatable. Buying an unproven product before checking those is the expensive order of operations. Read why am I tired all the time first, and treat NAD+ as a decision to make afterwards rather than instead.

Stacking NAD+ with testosterone therapy

Men on testosterone therapy often ask whether to add NAD+, and the honest answer is that it is a question for the physician managing your therapy rather than a recommendation we are going to make. There is no trial evidence that combining them improves any outcome, and there is no established interaction profile for injectable NAD+ because it has had very little formal study.

• One prescriber should see the whole plan. Whoever manages your testosterone should know about every other thing you inject or swallow, including supplements.
• Testosterone therapy stays diagnosis-gated. It is prescribed for men with hypogonadism confirmed by lab testing, and adding a second product does not change that requirement or the follow-up bloodwork that comes with it.
• Do not attribute effects to the wrong thing. Starting two treatments together makes it impossible to tell which one did anything, which is a practical argument for changing one variable at a time.
• There is no evidence of a synergy. Nobody has tested the combination, so any claim about it stacking is invention rather than data.

What you get at Expert Health

If, knowing all of the above, you want to try it under supervision, Expert Health prices NAD+ at $249 per month on the subscription, or $675 one time for a bottle covering about a 10-week supply:

• A free call with a health specialist, with no obligation to buy
• A US-licensed provider who reviews your history and can decline to prescribe
• NAD+ compounded by a licensed US pharmacy and shipped free and discreetly, with what you need to inject at home
• Provider check-ins, so the dose and frequency are matched to how you respond

Compounded medications are not FDA-approved, and NAD+ is prescribed off-label for energy and longevity goals. The full price breakdown is in how much NAD+ injections cost, and the molecule comparison is in NAD+ vs NMN vs NR.

Frequently asked questions

Sources

1. Effects of nicotinamide riboside on NAD+ levels, cognition, and symptom recovery in long-COVID: a randomized controlled trial · eClinicalMedicine, via PubMed, 2025
2. Chronic nicotinamide riboside supplementation is well-tolerated and elevates NAD+ in healthy middle-aged and older adults · Nature Communications, via NIH PMC, 2018
3. Chronic nicotinamide mononucleotide supplementation elevates blood NAD+ levels and alters muscle function in healthy older men · npj Aging, via NIH PMC, 2022
4. Physical performance parameters in patients taking nicotinamide mononucleotide: a systematic review of randomized controlled trials · Cureus, via NIH PMC, 2024
5. The differential impact of three different NAD+ boosters on circulatory NAD and microbial metabolism in humans · Nature Metabolism, via PubMed, 2025
6. Compounding and the FDA: questions and answers · U.S. Food and Drug Administration