NAD+ has become a buzzword in the wellness world. You may have seen it sold as a capsule, a powder, or an IV drip, often with big promises about energy and aging. But what is NAD+, really, and what does the science say so far? Here is a balanced look at what we know and what we do not.
What NAD+ is
NAD stands for nicotinamide adenine dinucleotide. You will often see it written as NAD+. It is a coenzyme, which is a helper molecule that enzymes need to do their jobs. The NIH Office of Dietary Supplements (ODS) explains that all tissues in your body turn niacin, also called vitamin B3, into NAD, its main active form.
NAD is busy. According to ODS, more than 400 enzymes need NAD to carry out reactions in the body, which is more than for any other coenzyme made from a vitamin. NAD helps turn the energy in carbohydrates, fats, and proteins into ATP, the main energy currency of your cells. It is also needed by enzymes that help keep DNA intact, control gene activity, and support communication between cells.
Where it comes from in your diet
Niacin comes in a few forms, including nicotinic acid, nicotinamide, and related compounds such as nicotinamide riboside, ODS notes. Animal foods like poultry, beef, and fish provide niacin, and so do plant foods such as nuts, legumes, and grains. Many breads and cereals in the U.S. have added niacin. Your body can also make some NAD from tryptophan, an amino acid found in protein.
A serious lack of niacin causes a disease called pellagra. ODS notes that pellagra is uncommon in industrialized countries and mostly affects people with very limited diets.
Why NAD+ gets linked to aging
Researchers are interested in NAD+ because levels decline during aging. A 2024 review in Cold Spring Harbor Perspectives in Medicine describes NAD+ as an essential molecule involved in energy production, DNA repair, and the ways cells clear out damaged parts. The authors discuss how NAD+ imbalance may play a role in aging and in diseases of the brain. They note that early lab and animal work with NAD+ precursors looks promising and that several clinical trials are underway.
That is where much of the excitement comes from. But results in animals do not always hold up in people.
What human studies have shown so far
Most human research has tested NAD+ precursors. These are building blocks the body can use to make NAD+, such as nicotinamide riboside (NR) and nicotinamide mononucleotide (NMN).
- They can raise NAD+ levels. A 2018 randomized, placebo-controlled trial in Nature Communications found that NR was well tolerated and boosted NAD+ metabolism in healthy middle-aged and older adults.
- Health effects are much less clear. A 2026 systematic review in Ageing Research Reviews looked at 33 human trials and 80 rodent studies. Rodent studies often showed improvements. In people, oral NR and NMN reached their biological targets and were generally well tolerated over weeks to months, but effects on actual health outcomes were mixed and often showed no benefit.
- Some measures did not change. A 2024 meta-analysis of eight randomized trials found that short-term NMN did not significantly improve blood sugar control or blood fats in mostly middle-aged and older adults.
The 2026 review concluded that while boosting NAD+ shows biological activity, its effectiveness for anti-aging or wellness outcomes remains inconclusive. The authors called for larger, longer, well-designed trials with clear health outcomes.
What about IV drips and injections?
NAD+ infusions are offered at some wellness clinics. The 2026 systematic review found no clinical trials of IV NAD+ for anti-aging. In other words, there is not yet trial evidence showing whether this approach helps with aging at all.
Supplements are not FDA-approved
NAD+ products sold as dietary supplements are not checked by the FDA for safety and effectiveness before they are sold. The National Center for Complementary and Integrative Health (NCCIH) explains that the FDA is not authorized to review supplements this way before they reach the market. NCCIH also notes that:
- What is on the label may not be what is in the product.
- Natural does not always mean safe.
- Some supplements can interact with medicines or affect surgery.
- Supplements cannot legally claim to diagnose, treat, cure, mitigate, or prevent any disease. Only drugs can make those claims.
So far, no NAD+ product has clear clinical trial evidence that it slows aging in people.
More is not always better
ODS notes that no harmful effects have been reported from niacin that occurs naturally in food. High doses from supplements are a different story. Large amounts of nicotinic acid can cause flushing, a red, burning, tingling, or itchy feeling in the skin. ODS also describes more serious effects at very high doses, including stomach problems, changes in blood sugar control, and signs of liver damage.
This is one reason to check with a clinician before adding any supplement, especially if you take other medicines or have a health condition. NCCIH also encourages you to tell your health care providers about any supplements you use.
Questions to ask your clinician
- Am I getting enough niacin from my diet?
- Is there any reason to think I am low in niacin?
- Could a supplement interact with my medicines or health conditions?
- What does the research actually show for my goals?
- Are there proven steps I should focus on first?
Talvi offers video visits with licensed clinicians. At Talvi, a licensed clinician reviews your health history before anything is prescribed.
The bottom line
NAD+ is a real and important molecule. Your body makes it from vitamin B3, and hundreds of enzymes depend on it. Research on NAD+ and aging is active and interesting. But so far, human studies show that precursors can raise NAD+ levels without clear proof that they slow aging or improve health. Be cautious with bold claims, and talk with a licensed clinician before you try any NAD+ product.