NAD⁺ is a helper molecule your cells need to make energy and repair themselves. NR and NMN are raw materials your body converts into NAD⁺, and in human trials both reliably raise NAD⁺ levels. NAD⁺ taken directly as a pill is mostly broken down before it reaches your cells, and IV drips have very little research behind them. The catch: raising NAD⁺ in healthy people has so far produced only small or no changes in energy, muscle or metabolism (how your body processes fuel). Promising chemistry, unproven benefits.
- SymptomLess energy, slower repair with age
- Before thatEnergy-making and repair enzymes slow down
- Before thatThey run short of their helper molecule
- RootNAD⁺ levels fall in some tissues with age
NAD⁺ in one minute
Every cell runs on ATP, a tiny rechargeable battery molecule. To recharge it, mitochondria, the power plants inside your cells, need a helper called NAD⁺. Think of it as a delivery van that shuttles energy around the power plant. NAD⁺ also fuels repair crews: enzymes, proteins (the cell's molecular machines) that each do one specific job, like fixing DNA, and sirtuins, proteins that help cells handle stress.
In animals and in some human tissues, NAD⁺ levels drop with age. The theory is simple: fewer vans, slower energy, slower repair. Top up the vans, and maybe things improve. That theory launched a whole supplement category.
The three options, compared
| Product | What it is | Raises NAD⁺ in humans? | Proven health benefit? |
|---|---|---|---|
| NR (nicotinamide riboside) | A form of vitamin B3 the body converts into NAD⁺ | Yes, in several trials | Not yet |
| NMN (nicotinamide mononucleotide) | The step right before NAD⁺ in the body's production line | Yes, in several trials | One small positive trial; otherwise not yet |
| NAD⁺ pills | The molecule itself | Mostly broken down in the gut first | No evidence |
| NAD⁺ IV drips | NAD⁺ infused into a vein | Raises blood levels during the drip | Very little research |
Why not just swallow NAD⁺? It's a fairly large molecule, and your gut and blood break most of it into smaller pieces before it gets anywhere useful. NR and NMN are smaller building blocks that cells can take in and assemble into NAD⁺ themselves.
What happens when people take them
NR in adults 55 to 79: NAD⁺ up, little else
A · Small trialSix weeks of NR raised a key NAD⁺ measure in blood cells by about 60 percent. Blood pressure showed a possible drop in people who started with high readings, but the researchers called the study a pilot and made no firm claims.[1]
NR in older men: muscle NAD⁺ up, energy unchanged
A · 12 menThree weeks of NR raised NAD⁺-related molecules inside muscle and lowered some blood markers of inflammation. But it did not change how well the muscle's mitochondria produced energy.[2]
NAD⁺ declines with age, so boosting it reverses aging.
Boosting NAD⁺ is easy. Showing that it makes people feel, perform or age better is not, at least not yet. The number in the blood went up; the outcomes mostly didn't move.
Why higher NAD⁺ might not be enough
Here's the upstream question most articles skip: why does NAD⁺ fall in the first place? Part of the answer is that the body uses it up faster with age, for example when repair enzymes work overtime on damaged DNA, and when long-running inflammation consumes it. If that's the real problem, adding more raw material treats the shortage but not the leak.
That would explain the pattern in the trials: levels rise, but cells don't necessarily work better. It's a plausible explanation, not a proven one. It's also why the bigger levers, exercise and keeping inflammation down, may matter more than the pill.
A note on legal status
In 2022, the US Food and Drug Administration (FDA) said NMN couldn't be sold as a dietary supplement because it was being studied as a drug. After a petition and a lawsuit from supplement industry groups, the FDA reversed that position in 2025, so NMN is again lawful to sell as a supplement in the US. Legal doesn't mean proven, and supplement quality varies, so look for products tested by an independent lab.
The bottom line
NR and NMN do exactly what they claim at the chemical level: they raise NAD⁺. Whether that translates into more energy or slower aging in healthy people is still an open question, and the human trials so far are small and short. If your goal is more energy, the evidence for training, sleep and fixing deficiencies is far stronger. If you're curious about NAD⁺ boosters, treat them as an experiment, not a fix.
Frequently asked questions
Is NMN or NR better?
Both raise NAD⁺ in human trials, and there's no good head-to-head trial showing one beats the other for health outcomes. NR has more published human studies so far.
Do NAD⁺ IV drips work?
There is very little controlled research on NAD⁺ infusions in healthy people. They're expensive and can cause discomfort during the drip. We'd wait for real trials.
Is NMN legal in the US?
Yes. After the FDA said in 2022 that NMN couldn't be sold as a supplement, it reversed that position in 2025 following a petition and lawsuit from industry groups. NMN can again be sold as a dietary supplement in the US.
Are NMN and NR safe?
In trials lasting weeks to a few months, both were well tolerated. Long-term safety in humans hasn't been established. Talk to your doctor first, especially if you have a medical condition or take medication.
Sources
- Martens CR, et al. Chronic nicotinamide riboside supplementation is well-tolerated and elevates NAD+ in healthy middle-aged and older adults. Nature Communications, 2018.
- Elhassan YS, et al. Nicotinamide riboside augments the aged human skeletal muscle NAD+ metabolome and induces transcriptomic and anti-inflammatory signatures. Cell Reports, 2019.
- Yoshino M, et al. Nicotinamide mononucleotide increases muscle insulin sensitivity in prediabetic women. Science, 2021.