NAD+ vs NMN: what to choose for longevity (table)

Nicotinamide adenine dinucleotide, abbreviated as NAD+, is a cofactor present in hundreds of enzymatic reactions: from energy production in mitochondria to DNA repair and sirtuin activity. For several years, it has been known that its concentration in human tissues negatively correlates with age, and this observation underpins the entire market for NMN and NR supplements. This article compares three forms that frequently arise in this discussion: NAD+ itself, its direct precursor NMN, and nicotinamide riboside. It also examines what human studies have really shown and where the evidence is weaker than marketing suggests. A practical note right away: Bucha’s store does not carry any preparation containing NAD+, NMN, or NR, so the text serves as a guide on the topic rather than a summary of the offer.

KEY INFORMATION
• NAD+ concentration in human skin tissue decreases with age, while the activity of the consuming enzyme PARP increases (Massudi et al., PLoS One, 2012).
• Oral NAD+ has no clinical protocols; human studies concern precursors: NMN and NR.
• NMN at a dose of 250 mg daily for 10 weeks improved muscle insulin sensitivity in postmenopausal women with prediabetes (Yoshino et al., Science, 2021).
• NR at doses of 100, 300, and 1000 mg daily raised NAD+ in the blood by 22, 51, and 142 percent over two weeks (Conze et al., 2019).
• A 2026 study in seven cohorts found no decrease in NAD+ in whole blood with age, questioning this measurement as an aging marker (Trętowicz et al., Nature Metabolism, 2026).
• Bucha’s store catalog does not contain preparations with NAD+, NMN, or NR (as of 2026-08-08).

What is NAD+ and why is its level tested in the context of aging?

NAD+ serves two distinct roles in the cell. The first is redox: the molecule accepts electrons and becomes NADH in glycolysis, the Krebs cycle, and beta-oxidation of fatty acids, driving ATP production in mitochondria. The second role is signaling. NAD+ is consumed by PARP enzymes that repair DNA damage, sirtuins that regulate gene expression and metabolism, and CD38, the main enzyme that breaks down this cofactor.

The hypothesis linking NAD+ to aging is based on measurements in human tissue. In a study of 49 skin samples taken from individuals aged from newborn to 77 years, NAD+ concentration negatively correlated with age in both sexes, and in men, PARP activity increased while SIRT1 activity decreased (Massudi et al., PLoS One, 2012). The authors proposed a mechanism: accumulating DNA damage excessively stimulates PARP, which consumes the NAD+ pool faster than the cell can regenerate it.

This explains why supplements targeting NAD+ have entered longevity protocols. However, it is important to note the scale of the evidence. The Massudi study covers one tissue and shows correlation, not causation, and the circulating number in guides about a decrease “by half after forty” does not come from this study or any other work that could be pointed out. A review from 2025 directly summarizes that the decrease in NAD+ in humans has been consistently confirmed only in a limited number of studies (Vinten et al., 2025). We review this entire category, with the five most commonly sold ingredients, in the text about longevity supplements.

What are the differences between NAD+, NMN, and NR?

Three forms related to this pathway are found in sales: NAD+ itself, nicotinamide mononucleotide (NMN), and nicotinamide riboside (NR). They differ in their position in the synthesis pathway and the number of studies in humans. The table below compares them based on characteristics that actually differ. It does not include prices or cost per serving, as Bucha’s store catalog does not contain any preparation from these three, and entering market prices would be guesswork.

What have studies shown about NMN in humans?

The study most cited by manufacturers is a Japanese safety study from 2020. Ten healthy men received a single oral dose of 100, 250, or 500 mg of NMN. No significant symptoms or changes in heart rate, blood pressure, and saturation were recorded, and the concentration of nicotinamide metabolites in plasma increased depending on the dose (Irie et al., Endocrine Journal, 2020). It is worth clarifying this, as supplement descriptions often cite this study as evidence of daily dose safety, while the study examined a single administration, not a treatment.

A stronger metabolic evidence came from a randomized study published in Science. Postmenopausal women with overweight or obesity and prediabetes took 250 mg of NMN daily for 10 weeks. In the NMN group, insulin-stimulated glucose uptake measured by hyperinsulinemic clamp increased, as did insulin signaling in muscle, which was not observed after placebo (Yoshino et al., Science, 2021). This is a narrow population and one endpoint, but methodologically solid.

The third trial involved active individuals. Forty-eight amateur runners were divided into four groups: 300, 600, and 1200 mg of NMN daily and placebo, with 5 to 6 training sessions per week for six weeks. In the 600 and 1200 mg groups, oxygen uptake and power at ventilatory thresholds improved, while VO2max did not change in any group (Liao et al., 2021). The authors explain the effect as better oxygen utilization by the muscle, not an increase in the oxygen threshold.

Does raising NAD+ levels really slow aging?

In mouse models, the result is clear. C57BL/6N mice were given NMN for twelve months, throughout normal aging. The animals gained less weight, had a more efficient energy metabolism, greater physical activity, better insulin sensitivity and lipid profile, and better eye function than the control group, with no signs of toxicity (Mills et al., Cell Metabolism, 2016). This study built expectations for the entire category.

However, recent years have brought results that temper these expectations. A team that measured NAD+ in whole blood in seven independent cohorts using validated mass spectrometry methods found no decrease in concentration with age or after lifestyle interventions. The level did respond to supplementation with nicotinamide riboside, meaning the method worked. The authors question the usefulness of NAD+ in blood as an aging marker (Trętowicz et al., Nature Metabolism, 2026).

The second breakthrough concerns muscle. In a model of mice with NAD+ synthesis disabled by NAMPT in adult skeletal muscle, the cofactor concentration dropped by 85 percent, yet morphology, contractility, exercise tolerance, and mitochondrial respiratory capacity were preserved. Lifelong deficiency did not accelerate muscle aging (Chubanava et al., Cell Metabolism, 2025). The conclusion for the reader is simple: a decrease in NAD+ does not have to be the cause of what marketing attributes to it, and measurement in blood says little about what happens in tissues.

How to raise NAD+ levels without NMN supplementation?

The best-documented intervention is exercise. In a study involving young (up to 35 years) and older (over 55 years) individuals, twelve weeks of aerobic training increased NAMPT levels in skeletal muscle by 12 percent in younger and 28 percent in older individuals, while resistance training increased them by 25 and 30 percent, respectively (de Guia et al., Physiological Reports, 2019). NAMPT limits the rate of the NAD+ recovery pathway, and its amount decreases with age, so training reverses this element.

The second route is diet. Niacin and nicotinamide, two forms of vitamin B3, enter the NAD+ pool via the recovery pathway, while tryptophan feeds it via the de novo pathway. Both components are provided by a regular diet with meat, fish, legumes, and whole grain products, and extreme deficiency of vitamin B3 (pellagra) leads to multi-organ symptoms. Preparations with B vitamins are in the supplements category. Therefore, deficiency has high stakes, but that does not mean that excess provides additional benefits to a well-nourished person.

The third conclusion is negative and also counts. Popular recommendations in guides, from intermittent fasting to sauna and cold baths, are based on mechanisms described in rodents, not on measurements of NAD+ in human tissues. A review from 2025 states directly that published data on NAD+ dynamics in humans is scarce, and transferring results from animal models is not straightforward (Vinten et al., 2025). If you are looking for interventions with solid evidence in humans, exercise remains the option.

What to look for when buying and what you won’t find at Bucha?

Let’s start with a fact that changes the way to read this article. A review of the entire catalog of Bucha’s store from August 8, 2026, covering the names and full descriptions of all 386 products, found not a single preparation containing NAD+, NMN, or nicotinamide riboside. There is also no standalone resveratrol, and what remains after subtracting marketing is checked in the text about resveratrol and aging. Therefore, the product comparison cannot be filled with the store’s offer, and a text that would do so would describe phantom positions.

So what is in the catalog that actually touches on the topic? Preparations with B vitamins, including niacin and nicotinamide, which are forms of vitamin B3 that enter the NAD+ pool. You will find them in the supplements category, where they stand alongside preparations with magnesium, vitamin D3, and omega-3 acids. These are not substitutes for NMN and should not be presented as such: they provide a basic substrate, not a direct precursor.

If you still buy NMN elsewhere, check three things on the label. First, the dose per serving, not per package, because the protocols from studies range from 250 to 1200 mg daily, and without this number, you cannot compare products. Second, a purity declaration with a batch number and testing from an external laboratory. Third, the expiration date and recommended storage method, as manufacturers of these compounds most often indicate a cool and dry place. Separately, we described what is known about NMN and supplementation after forty, along with the status of this ingredient as a novel food in the EU.

What is known about the safety of NMN and NR?

Safety data are short-term, and this is their biggest limitation. For NMN, the best-documented is a single administration of up to 500 mg in healthy men, with no significant changes in vital or laboratory parameters (Irie et al., Endocrine Journal, 2020). For NR, we have an eight-week randomized trial with a placebo control: doses of 100, 300, and 1000 mg daily raised NAD+ in whole blood by 22, 51, and 142 percent over two weeks, with no difference in adverse events compared to placebo and no increase in LDL cholesterol (Conze et al., Scientific Reports, 2019).

What do we not know? First, the effects of supplementation longer than several weeks in humans have simply not been studied. Second, there is no trial comparing NMN with NR on the same endpoints, so claims like “NMN beats NR” are based on comparing incomparable studies. Third, a review from 2025 summarizes the effectiveness of NAD+ precursors in clinical studies in humans as limited, despite promising preclinical results (Vinten et al., 2025).

Caution is advised for individuals undergoing cancer treatment and those taking medications regularly. Not because harm has been demonstrated, but because published data comes from small groups of healthy volunteers and does not cover such situations. The decision to supplement with a chronic illness should be made with the attending physician, not based on a product description in an online store.

Frequently Asked Questions

What is the difference between NAD+ and NMN?

NAD+ is a ready cofactor used by enzymes, while NMN is its direct precursor from which the cell regenerates NAD+. Oral NAD+ does not have an established clinical protocol because the molecule is broken down in the digestive tract. Human studies are conducted on precursors, namely NMN and nicotinamide riboside.

How much NMN was used daily in human studies?

The range from published trials is 250 to 1200 mg daily for 6 to 10 weeks. The safety study by Irie and colleagues from 2020 examined a single dose of 100, 250, and 500 mg in ten healthy men, not a treatment, and this distinction is often blurred in supplement descriptions.

Is NMN better than NR?

There is no study comparing both compounds on the same endpoints, so the answer is: it is unknown. NR has a longer trial with a placebo control and measured an increase in NAD+ in the blood, while NMN has metabolic evidence in muscle. Comparing these studies is like comparing incomparable results.

Does supplementation with NAD+ or NMN extend life?

There is no such evidence in humans. Annual administration of NMN to mice alleviated some age-related changes, but in humans, only intermediate markers have been measured in several-week trials. Lifespan was not an endpoint in any published trial. A review from 2025 summarizes the effectiveness of NAD+ precursors in clinical studies as limited.

Is it worth testing NAD+ levels in the blood?

A 2026 study measured NAD+ in whole blood in seven independent cohorts and found no age-related changes or lifestyle intervention effects. The concentration responded only to supplementation. The authors question the value of this measurement as an aging marker in healthy individuals.

Can I buy NMN or NAD+ at Bucha’s store?

No. A review of the entire store catalog from August 8, 2026, covering the names and descriptions of all 386 products, found no preparation containing NAD+, NMN, or nicotinamide riboside. However, preparations with B vitamins, including niacin and nicotinamide, are available.

If you are looking for preparations that are actually in stock and support daily intake of B vitamins, check the supplements category, the only one in the store where these preparations are actually available. Catalog status checked on August 8, 2026.

This article is for informational and educational purposes only and does not constitute medical advice. Before starting supplementation, consult your doctor, especially if you are taking medications regularly, are pregnant or breastfeeding, or have a chronic illness.

Author: Michał Waluk · Published: 2026-08-05 · Updated: 2026-08-08