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When Sonia searched “NAD” in the app she uses to message her patients to prepare for this episode, seven conversations came up.
The one that stayed with her came from a patient who sent a photo of a brochure she’d picked up at a wellness clinic. It advertised NAD+ IV therapy as “the foundation of youth,” promising a drip that would support brain function, fight chronic fatigue, boost metabolism and energy, reduce inflammation, and possibly slow the aging process. It described NAD+ as a miracle molecule, the closest thing we have to a fountain of youth.
Her next message read: “I just need something natural that isn’t going to kill me.”
This patient was exhausted, foggy, bloated, achy, and dealing with rashes no one had explained. She was also afraid—not of her symptoms so much as of medicine itself. Medications, vaccines, specialists, even tests felt threatening, because any of them might end with someone telling her something was wrong and handing her a prescription she didn’t want. Her instinct when she felt unwell was: I can fix this myself, if I just find the right thing.
The brochure seemed to offer exactly that. Something that sounded gentle. Something that sounded natural. Something that promised to help her body do more of what it already does.
It’s easy to understand why it landed. And it’s worth taking seriously, because NAD+ is a real and genuinely important molecule, the research on it is real, and the answer to whether these products help is more interesting than a simple yes or no.
So let’s slow down and ask: are NAD+ supplements and IVs worth it?
The Claim
If you spend time on social media, you’ve probably seen NAD+ described as something close to a cellular cure-all. The claims tend to cluster into a few big promises. For longevity, it’s pitched as a way to “reverse aging,” “repair DNA,” and support “cellular rejuvenation.” For energy and productivity, it promises less brain fog, sharper focus, “mitochondrial support”, and recovery from burnout. For the body, the claims include glowing skin, a faster metabolism, and better workouts and muscle recovery. It’s increasingly marketed to women in perimenopause as a way to restore vitality and fix fatigue. And it shows up in detox and recovery spaces too, promoted for hangovers, alcohol recovery, and clearing “toxins.”
NAD+ is sold in two main ways. Oral supplements usually contain NAD+ precursors—building blocks with names like nicotinamide riboside (NR) and nicotinamide mononucleotide (NMN). IV drips are offered at wellness clinics, med spas, and IV bars, often as a multi-day “loading” series. The logic behind the marketing is simple: NAD+ is involved in energy production, DNA repair, and metabolism, so more NAD+ should mean more of all of those good things.
Why It’s Going Viral
Part of the answer is that the science genuinely has evolved. Nicotinamide riboside was first described in 1944, but it wasn’t until around 2004 that researchers mapped out its full role in making NAD+. Most of the research on NAD+ precursors has come out in the last twenty years, and most of the human data in just the last five or six. This isn’t an old idea dusted off for a new audience; there’s real, recent research here, and that lends it credibility.
NAD+ also sits right at the intersection of some of the biggest health conversations happening online: longevity, metabolic health, inflammation, and optimization, even for people who feel basically well. Many people are living with fatigue, brain fog, and burnout—vague, draining ways of feeling unwell that don’t always have a clear explanation or an easy fix. Fear about perimenopause has many women looking for anything proactive they can do. And growing worry about environmental toxins makes the idea of “detoxing” feel urgent.
Then there’s the appeal of the hack. Many of us know, on some level, that we aren’t sleeping enough, moving enough, or managing stress the way we’d like. But knowing that doesn’t make it possible to change. You can’t sleep more with a newborn. You can’t make a demanding job less stressful. You can’t get to the gym with an injury or no spare hour. NAD+ is often pitched as a way to offset the damage you already know is happening. It’s the wish for a pill—or a drip—that undoes what life is doing to us. That wish is deeply human.
Finally, there’s the pull of “natural.” Medical care can cause harm. Over-medicalization is real, medical errors are real, and many people have been dismissed, rushed, or handed a prescription when they wanted to be heard. When someone has been hurt by or has lost trust in the medical system, something that sounds like it simply helps your body make more of what it already makes can feel like the safer choice. That instinct makes sense—even when, as we’ll see, it doesn’t always hold up.
What the Science Shows
First, what is NAD+?
NAD+ (nicotinamide adenine dinucleotide) is a coenzyme found in every living cell. It isn’t a peptide, despite often being grouped with them online. It shuttles electrons in the chemical reactions that produce energy, cycling between an oxidized form (NAD+) and a reduced form (NADH). It also fuels enzymes involved in metabolism, DNA repair, gene expression, stress responses, and immune function. So it’s true that NAD+ plays a role in nearly everything the marketing mentions.
Your body makes NAD+ on its own. It can build it from tryptophan and from nicotinic acid (a form of vitamin B3) in food, and it can assemble it from precursors like nicotinamide (NAM), NR, and NMN. That precursor pathway is the main way cells keep their internal NAD+ supplied.
Here’s the important part: NAD+ itself is a large molecule that doesn’t easily get into cells. Think of it like a big couch you’re trying to move through a narrow apartment door. It’s much easier to bring the couch in pieces and assemble it inside. That’s why most supplements contain precursors, the pieces, rather than NAD+ itself. Your gut microbiome also appears to play a role, likely converting NMN to NR before it’s absorbed.
The promising part: animal studies
NAD+ levels drop in tissues like the brain, liver, heart, and muscle as people get older and in the setting of chronic disease. Researchers still debate how much of that decline is aging itself versus the conditions that become more common with age. Viral infections, chronic inflammation, sleep disruption, and metabolic disease have all been linked with lower NAD+, though much of that evidence comes from animal models.
In those preclinical studies (animals and cells, not people), NAD+ precursors improved glucose and lipid metabolism, reduced blood vessel dysfunction, and protected heart tissue from injury. The results look strong. But as we talk about often on this podcast, what happens in mice doesn’t reliably predict what happens in people. So the question that matters is: what does the human data show?
What happens in people who take oral supplements
A helpful 2023 review pulled together the human trials of NAD+-boosting supplements, and the most data exists for NR and NMN.
For NR, the review included twelve studies with doses ranging from 250 to 2,000 mg a day and durations from one to twenty weeks. Most were placebo-controlled, but all were small, with eight to forty participants. Some enrolled healthy adults; others enrolled people with specific conditions. Two consistent findings emerged. First, oral NR was generally safe and well tolerated for the doses and durations studied, with no serious adverse events; reported side effects included nausea, diarrhea, rashes, and leg cramps. Second, NR reliably raised NAD+ levels in the blood.
That second finding is where a lot of marketing stops, and it’s worth pausing on. Raising a number in the blood is not the same thing as helping a person feel or function better. Family medicine has a name for the evidence that really counts: “POEM” or “patient-oriented evidence that matters”. We aren’t treating a lab value; we’re caring for a human being.
When researchers looked for outcomes that matter, the picture got much quieter. For people with cardiometabolic risk, one study found a 2.5 mmHg drop in blood pressure that wasn’t statistically significant after adjustment, and a later, larger trial designed specifically to study blood pressure found no change. A 2023 meta-analysis did report small reductions of about 2.5 mmHg systolic and 2 mmHg diastolic, mostly at higher doses, over longer periods, and with nicotinic acid. The best summary is that the blood pressure data is mixed, and any effect appears modest.
The strongest trial in the review was randomized, double-blind, and placebo-controlled. It gave 40 sedentary men aged 40 to 70 with a BMI over 30 a total of 2,000 mg of NR daily for twelve weeks. Based on the animal data, researchers expected metabolic benefits. Instead, NAD+ didn’t rise in muscle tissue, and there was no effect on insulin sensitivity, body composition, or any other metabolic measure. Twelve weeks is short for some of those outcomes, and supporters argue that longer, better-funded trials might tell a different story. That’s fair. But it’s also what the best evidence we have shows today. Across studies, there’s no consistent improvement in exercise capacity either.
For people living with long COVID, where the idea is that illness-related inflammation drains NAD+ stores, a randomized controlled trial gave 58 participants 2,000 mg of NR daily. NAD+ levels rose two- to threefold, yet there was no difference compared with placebo in fatigue, sleep quality, or mood.
NMN tells a similar story. The review included thirteen studies, all published between 2021 and 2023, with 17 to 108 participants, doses of 250 to 1,250 mg daily, and durations from two to twenty-four weeks. NMN was safe and well tolerated and raised NAD+ levels. A few studies showed some cardiometabolic benefit, but most showed no change in physical function or cardiometabolic health.
NMN has also had an unusual regulatory journey that’s worth understanding. In late 2022, the FDA said NMN could no longer be sold as a dietary supplement because it had been authorized for investigation as a drug. In September 2025, after industry petitions and a lawsuit, the FDA reversed course and concluded NMN can be marketed as a supplement after all. The back-and-forth shows how blurry the line between “supplement” and “drug” can be. It’s also a reminder that supplements aren’t necessarily tested for purity or potency before they reach shelves, so what’s on the label may not match what’s in the bottle.
The IV question
This is where the evidence doesn’t just get thin; it essentially disappears. There’s no meaningful clinical data showing that IV NAD+ is safe, well tolerated, or better than taking a precursor by mouth.
The only published study we could find was a retrospective chart review from a commercial wellness clinic, published in Frontiers in Aging in 2026. It compared six clients who received IV NAD+ with eight who received IV NR. Each client got four daily infusions as a “loading” series, a protocol we couldn’t find any evidence to support. There was no placebo, no control group, no randomization, no blinding, and no prespecified outcomes.
And even so, the results are striking. All six people in the NAD+ group experienced moderate to severe abdominal cramping, diarrhea, nausea, vomiting, increased heart rate, throat pain, congestion, and chest pressure during their infusions. The symptoms stopped when the infusions ended. Five out of eight people in the NR group reported tingling in the tongue, jaw, and arm, along with cramping. Clients were allowed to control their own infusion rate, which isn’t how IV medications are given in medical settings, where rates are set based on each person’s health and risk factors. NAD+ infusions averaged 96 minutes; NR infusions, 37.
The lab results thirty days later were hard to interpret. Most values didn’t change. HDL cholesterol, the kind you generally want to be higher, dropped in the NAD+ group. HbA1c dropped in the NR group, which is surprising, since A1c reflects blood sugar over roughly three months. With so few people, and no information about other medications or changes, it’s impossible to draw meaningful conclusions. The paper describes itself as a tolerability study. It’s hard to read it and come away feeling reassured.
Cost matters too. Oral NAD+ precursors typically run about $30 to $150 a month. IV infusions can cost $300 to $1,000 or more per session, and a multi-day loading series multiplies that.
IVs also carry risks of their own, regardless of what’s in the bag. Any time the skin is broken and something is put directly into a vein, there’s a risk of infection, bruising, pain, phlebitis (inflammation of the vein), and clotting. Repeated IVs can damage veins, making it harder to get access in a real emergency. Add-ins mixed into the drip raise questions about interactions. And when side effects are normalized as something to push through, a serious reaction can be missed. In Texas, a woman died after receiving an IV of a lethal dose of electrolytes by an unlicensed person at a med spa in 2023, a case that’s now being prosecuted.
Clinical Nuance
None of this means NAD+ is useless or that anyone curious about it has been fooled. The biology is real, the animal data is genuinely promising, and the fact that NMN has been investigated as a drug suggests these compounds may turn out to have a role for specific conditions. The honest answer is that we need better studies to find out who might benefit, at what dose, by what route, and for what.
Until then, thoughtful clinicians tend to come back to a few questions: In whom? For what? And how strong is the evidence for that? For most people looking for more energy or slower aging, the current human data doesn’t show a clear benefit from oral supplements. But because oral NR and NMN have looked safe in the short term, there’s room for individualized decisions. For someone who has already worked through the evidence-based options for a condition like long COVID, chronic pain, or fibromyalgia and wants to try something else, a monitored trial of an oral precursor, with realistic expectations, can be a reasonable shared decision.
IV NAD+ is different. When deciding whether anything belongs in an IV, the first question is: is there a reason it can’t be taken by mouth? In medicine, IV treatment is typically used when someone can’t tolerate oral treatment or needs something faster than oral can provide. For NAD+, there’s no evidence of benefit from IV administration, no evidence it’s better than oral, and early signs that it can feel quite bad. When IV NAD+ appears on a clinic’s menu of services, it’s fair to ask how that clinic weighs evidence against revenue.
There’s also a quieter harm that doesn’t show up in any study: delay.
Remember the patient with the brochure? When she and Dr. Singh met again, they found real opportunities to help: she wasn’t drinking much water, wasn’t sleeping much with small children at home, and was struggling to eat regular meals. Those were real, and so was the fact that her life made them genuinely hard to change, which is part of what made a drip so tempting. But her labs also showed inflammation. After a long time and a lot of hesitation, she saw a rheumatologist and was diagnosed with lupus, a condition she had likely been living with for years while trying to manage it on her own.
Even if an oral NAD+ supplement had helped her feel a little better, that could have been bad news if it delayed a diagnosis and treatment that protect her kidneys, eyes, and joints. It’s the same concern we’d have about a painkiller that masks symptoms. Lifestyle absolutely has a role in managing lupus. But lupus isn’t a lifestyle-only condition, and compared with evidence-based treatment, an IV of NAD+ is not the safer choice.
This is why dismissing these questions doesn’t work. Patients who feel brushed off often go right back to the places selling the drip. What helps is a clinician willing to say: I hear why this appeals to you, here’s what we know and don’t know, and let’s figure out what’s really going on together.
The Antidote
For Patients
(Gentle reminders and affirmations)
It makes sense that I want something that helps me feel less exhausted.
Wanting a natural option doesn’t make me naive.
Raising a number in my blood is not the same as feeling better.
“Natural” and “safe” aren’t the same thing, and an IV is a medical procedure no matter what’s in the bag.
When something promises to fix everything, I’m allowed to pause and ask questions.
My fatigue deserves a real evaluation, not just a quick fix.
Getting a diagnosis doesn’t mean losing control of my care.
For Clinicians
(Language you can borrow, tweak, or make your own)
“I’m really glad you brought this up. Let’s talk about what we know and what we don’t know about NAD+.”
“I understand why this sounds appealing. It promises a lot of what you’re looking for.”
“The supplements do raise NAD+ levels in the blood, but we care about whether you feel and function better, and so far the studies mostly don’t show that.”
“When I think about whether anything belongs in an IV, my first question is whether there’s a reason it can’t be taken by mouth. For NAD+, I can’t find one.”
“If you want to try an oral supplement, I’m open to that. Let’s decide together what we’re hoping it will help with, and check in on how it’s going.”
“I don’t want a supplement to feel better in the short term while we miss something that needs treatment. Let’s make sure we understand what’s causing how you feel.”
Sources and Further Reading
Freeberg KA, Udovich CC, Martens CR, Seals DR, Craighead DH. Dietary Supplementation With NAD+-Boosting Compounds in Humans: Current Knowledge and Future Directions. J Gerontol A Biol Sci Med Sci. 2023.
https://pmc.ncbi.nlm.nih.gov/articles/PMC10692436/Hawkins J., Idoine R., Kwon J., Shao A., Dunne E., Hawkins E., et al. (2024). Randomized, placebo-controlled, pilot clinical study evaluating acute niagen®+ IV and NAD+ IV in healthy adults. Prepr. medRxiv. 10.1101/2024.06.06.24308565 https://www.medrxiv.org/content/10.1101/2024.06.06.24308565v1
Damgaard MV, Treebak JT. What Is Really Known About the Effects of Nicotinamide Riboside Supplementation in Humans. Sci Adv. 2023.
https://pubmed.ncbi.nlm.nih.gov/37478182/Effects of NAD+ precursors on blood pressure, C-reactive protein concentration and carotid intima-media thickness: A meta-analysis of randomized controlled trials. Eur J Clin Invest. 2023.
https://onlinelibrary.wiley.com/doi/10.1111/eci.14078Effects of nicotinamide riboside on NAD+ levels, cognition, and symptom recovery in long-COVID: a randomized controlled trial. 2025.
https://pubmed.ncbi.nlm.nih.gov/41357333/Intravenous infusion of nicotinamide adenine dinucleotide (NAD+) versus nicotinamide riboside (NR): a retrospective tolerability pilot study in a real-world setting. Front Aging. 2026.
https://pubmed.ncbi.nlm.nih.gov/41704678/The Regulatory Role of NAD in Human and Animal Cells. 2018.
https://pubmed.ncbi.nlm.nih.gov/30200865/Nicotinamide Adenine Dinucleotide (NAD+): Essential Redox Metabolite, Co-Substrate and an Anti-Cancer and Anti-Ageing Therapeutic Target. 2020.
https://pubmed.ncbi.nlm.nih.gov/32573651/Nicotinamide Adenine Dinucleotide in Aging Biology: Potential Applications and Many Unknowns. 2023.
https://pubmed.ncbi.nlm.nih.gov/37364580Impact of Geroscience on Therapeutic Strategies for Older Adults With Cardiovascular Disease: JACC Scientific Statement. J Am Coll Cardiol. 2023.
https://pubmed.ncbi.nlm.nih.gov/37389519/Abdellatif M, Sedej S, Kroemer G. NAD+ Metabolism in Cardiac Health, Aging, and Disease. Circulation. 2021.
https://www.ahajournals.org/doi/10.1161/CIRCULATIONAHA.121.056589Venable LLP. FDA Declares Nicotinamide Mononucleotide Is a Dietary Supplement. 2025.
https://www.venable.com/insights/publications/2025/10/fda-declares-nicotinamide-mononucleotide-is