Nicotinamide Mononucleotide (NMN)

Nicotinamide Mononucleotide (NMN and β-NMN) is a compound found naturally in the cells of our bodies and is integral to several cellular processes. NMN is a direct precursor to NAD+, a vital coenzyme essential for a myriad of cellular functions. The levels of NAD+ are known to decline as we age, and this decline is associated with aging and various age-related diseases. The has been shown in several clinical trials that by supplementing with NMN, we can boost the levels of NAD+ in the body, potentially counteracting age-related cellular decline and improving overall health. Preliminary studies, mainly in mice, suggest that NMN supplementation could offer a range of health benefits, such as enhanced energy metabolism and improved DNA repair, indicating its potential role in slowing the aging processes.

However, while NMN shows significant promise, comprehensive studies determining its long-term safety, effective dosage, and potential side effects in humans are still in progress. NMN is also present in several food sources, including broccoli, cabbage, cucumber, avocados, and edamame, but only in small quantities.

NMN and its impact on longevity are at the cutting edge of anti-aging research, with new discoveries and insights emerging regularly, deepening our understanding of the aging process and potential interventions to extend health and lifespan.

Sources of NMN in Food

NMN is naturally present in a variety of foods, albeit in relatively small quantities. Here is a list of some foods known to contain NMN, along with their respective NMN content.

Food Type	Name	NMN Content (mg/100g-Food)
Vegetable	Edamame	0.47–1.88
Vegetable	Broccoli	0.25–1.12
Vegetable	Cucumber Seed	0.56
Vegetable	Cucumber Peel	0.65
Vegetable	Cabbage	0.0–0.90
Fruit	Avocado	0.36–1.60
Fruit	Tomato	0.26–0.30
Other	Mushroom	0.0–1.01
Meat	Beef (raw)	0.06–0.42
Seafood	Shrimp	0.22

While these foods can contribute to NAD+ levels through the provision of NMN, the quantities present are relatively small, and it is currently unclear whether dietary intake alone can significantly impact NAD+ levels in the body. Therefore, research into NMN supplementation is ongoing to explore its potential in maintaining or elevating NAD+ levels and mitigating age-related decline.

Legal

European Union (EU)

In the European Union, the classification and regulation of substances are often determined by their intended use and the claims made by the manufacturer or distributor. As of the latest update, Nicotinamide Mononucleotide (NMN) is classified as a chemical in the EU and has not been approved for human consumption. This classification is due to the EU's stringent regulations surrounding novel foods and substances, emphasizing consumer safety.

While NMN is not approved for human consumption in the EU, consumers may come across NMN products online that appear to be marketed for human use. However, these are officially sold either as chemicals for research and laboratory purposes or as supplements for animals, including dogs and cats. It is important for consumers to recognize the legal status and potential risks of such unapproved substances.

United States (US)

In November 2022, the US Food and Drug Administration (FDA) issued a statement saying that NMN may not be sold as a supplement, citing its status as being under investigation as a drug. This development is a reversal of the FDA's previous decision to allow its sale as a new dietary supplement (NDI). The reason for the reversal is unknown, but in December 2021, Metro International Biotech, a startup pharmaceutical company that has developed the NMN formulation MIB-626, wrote to the FDA: "As a company that has instituted publicly available clinical trials on ß-NMN, we request that FDA take the preclusion provision … seriously to protect the rights of companies that have spent significant time and research to develop drug products from competition from dietary supplements". According to Insider, the FDA confirmed that it had considered Metro's request.

Different Forms of NMN

Nicotinamide Mononucleotide (NMN) exists in two stereoisomeric forms, α-NMN and β-NMN, which have the same molecular formula but differ in the spatial arrangement of atoms. Recent advancements in NMN supplementation have led to the development of various formulations aimed at enhancing the compound's bioavailability and efficacy.

β-NMN

β-NMN is the biologically active form of NMN, predominantly utilized in scientific studies and supplements. It is integral in the biosynthesis of Nicotinamide Adenine Dinucleotide (NAD+), a vital coenzyme involved in numerous cellular processes, including energy metabolism, DNA repair, and cellular aging. When references are made to NMN in the context of supplementation or scientific research, it typically pertains to β-NMN due to its biological significance and activity.

α-NMN

α-NMN, on the other hand, does not participate in NAD+ biosynthesis and lacks the biological activity and associated health benefits of β-NMN. It is not the focus of NMN-related research or supplementation.

Liposomal NMN

Liposomal NMN is a form of NMN that is encapsulated within liposomes to enhance stability and bioavailability. This dietary supplement is available on the market and is being explored for its potential to increase the effectiveness of NMN supplementation. However, as of the latest updates, there are no published clinical studies specifically validating the benefits and efficacy of liposomal NMN, which means that while the theoretical advantages are promising, they have not yet been confirmed by scientific research.

MIB-626

MIB-626 doses of 1,000 mg taken once daily over 14 days doubles NAD+ levels (middle graph). When taken twice daily, MIB-626 triples NAD+ levels (right graph). The placebo capsules had no effect on NAD+ levels (left graph).

MIB-626, developed by Metro International Biotech, is a microcrystalline form of NMN. This formulation may offer enhanced stability, solubility, or bioavailability compared to the regular crystalline form of NMN, potentially optimizing the efficacy of NMN supplementation. MetroBiotech plans to bring MIB-626 on the market as drug, not as dietary supplement. For that reason, several clinical trials are ongoing evaluating the effects and safety of MIB-626 on humans.

Early results have indicated that a dosage of 1000 mg over 14 days can raise NAD+ levels (AUClast) about factor 1.7, and 2000 mg can increase by factor 3.7 above baseline in overweight or obese adults.

Reduced NMN (NMNH)

Reduced Nicotinamide Mononucleotide (NMNH) is a novel, potentially more effective NAD+ precursor.

NMN-HAP

NMN-HAP is a hydroxyapatite-based nano-drug delivery system for nicotinamide mononucleotide that showed significantly enhancing NMN bioavailability and replenishing NAD+ levels in mice. NMN-HAP is currently not available as supplement.

Metabolism of NMN

Bioavailability

Levels of NAD+ and NAMN in blood were increased by oral administration of 250mg NMN. NAD metabolome in blood was measured every 4 weeks. Three asterisks mean statistical significance: p-value < 0.001.

Bioavailability is a crucial factor in the effectiveness of any dietary supplement, including Nicotinamide Mononucleotide (NMN). It refers to the proportion of a substance that enters the circulation when introduced into the body and is thus able to have an active effect. In the case of NMN, bioavailability determines how much of the compound reaches the bloodstream and subsequently contributes to NAD+ biosynthesis. One of the main challenges with NMN bioavailability is its absorption and transportation within the body. When taken orally, NMN needs to be absorbed through the gastrointestinal tract, which can present barriers to its effective uptake.

• Molecular Size: NMN's relatively large molecular size compared to other NAD+ precursors (like NR, or nicotinamide riboside) poses a challenge for its absorption in the gut.
• Enzymatic Degradation: NMN can be subject to degradation by enzymes in the digestive tract, potentially reducing the amount that actually enters the bloodstream.

To address these challenges, various strategies and formulations have been developed:

• Liposomal Encapsulation: Liposomal NMN involves wrapping NMN molecules in a lipid layer, which can help protect them from degradation in the digestive system and enhance absorption.
• Sublingual Administration: Taking NMN sublingually (under the tongue) is proposed to increase its bioavailability by allowing direct absorption into the bloodstream, bypassing the digestive system.
• Microcrystalline Formulation: MIB-626, a microcrystalline form of NMN developed by MetroBiotech, is believed to offer enhanced stability and bioavailability.

While various methods to enhance NMN’s bioavailability are being explored, conclusive evidence on the most effective form or administration method is still emerging. Current research is focused on understanding how different formulations affect NMN's absorption and utilization in the body. Future studies are expected to provide more insights and possibly lead to more effective NMN supplementation strategies.

Effect

• Taking 800 mg NMN per day increase blood cell NAD+ levels by ~43% in mild hypertension patients display significantly lower blood cell NAD+ levels.
• Taking 300 mg NMN per day increase serum NAD+/NADH ratio by ~38%.
• It is assumed that the NAD+ level increases continuously through the NMN intake until it reaches its maximum after 1-2 weeks.^{[Citation needed]}

	After	NMN Group			Placebo Group			NMN group
		NAD+ concentrate [µM]			NAD+ concentrate [µM]			NAMN
		Baseline	After	Factor	Baseline	After	Factor	After
Whole blood, 250 mg/day	12 weeks	0.176±0.063	1.07±0.16	6.1	0.194±0.081	0.53±0.12	2.7	3.51±1.86
250 mg/day	12 weeks	~22	~38	1.72	~21	~22	~1	~1.45
250 mg/day	12 weeks	0.006 (mean)	0.026 (mean)	(4.3)
800 mg/day (pmol/mg protein)	12 weeks	14.81±11.68	21.19±11.83	1.43	16.20±10.37	16.15±8.56	~1

Combination Therapy for Enhanced NAD+ Levels

A variety of nutritional supplements are available in the market, which contains the compositions of NMN coupled with natural products. Despite this, the synergistic effects and transformation processes of NMN in such combinations are not fully understood.

In a recent study, oral administration of NMN (500 mg/kg) was combined with either resveratrol (50 mg/kg) or ginsenosides (Rh2 & Rg3) (50 mg/kg) in C57BL/6 mice to assess the efficacy of these drug combinations. The results showed that the combination could increase NAD+ levels in specific mouse tissues compared to NMN alone:

• With Resveratrol: NAD+ levels increased approximately 1.6 times in the heart and 1.7 times in muscle tissue.
• With Ginsenosides (Rh2 & Rg3): NAD+ levels in lung tissue improved by about 2.0 times.

These findings suggest that combining NMN with specific natural products like resveratrol or ginsenosides may amplify the beneficial effects on NAD+ levels, offering new avenues for treating age-related diseases or conditions linked to decreased NAD+ levels in specific tissues.

Clearance

It is currently assumed that NAD+ levels return to baseline within 1-2 weeks after ceasing NMN administration.^{[Citation needed]} In two clinical trials, NAD+ levels were measured four weeks after discontinuation of NMN and were found to be back to baseline.

Controversy about NMN as Direct Precursor

NMN administration of NMN–HAP and free NMN increases plasma NAD+ and NR in mice

NMN is often advertised, for example by NMN suppliers, as a direct precursor to NAD+, purportedly making it more effective compared to other precursors like Nicotinamide Riboside (NR). However, NMN's role as a direct precursor is only effective when it is inside the cell. This raises questions about how NMN, when ingested or administered externally, enters the cell to contribute to NAD+ synthesis. The central controversy surrounding NMN as a precursor to NAD+ lies in its mechanism of cellular entry. While NMN is a direct precursor of NAD+ within the cell, the debate focuses on whether NMN can be directly absorbed by cells or if it must first be converted to NR. In that case, NR might have an advantage over NMN, as NMN would require one additional conversion step compared to NR.

1. Direct Transport Mechanism: One hypothesis suggests that NMN can directly enter cells through specific transporters. The Slc12a8 transporter in the aged mouse ileum has been suggested to facilitate NMN's direct absorption. However, this idea has faced challenges due to conflicting research findings, and the functionality of Slc12a8 in humans has yet to be conclusively determined.
2. Dephosphorylation to NR: An alternative and currently more widely accepted theory proposes that NMN is not directly utilized by cells. Instead, it is first converted to Nicotinamide Riboside (NR) through dephosphorylation before cellular absorption. This conversion is mediated by enzymes like CD73. Once inside the cell as NR, it is then phosphorylated into NMN.

While direct transportation into the cell and dephosphorylation to NR can coexists, studies in mice indicate that orally ingested NMN is predominantly converted to NR in the intestinal tissue before absorption, challenging the view of NMN as a direct precursor to NAD+.

Potential Longevity Benefits

NMN supplementation has been associated with several potential benefits, primarily due to its role as a precursor to NAD+, a crucial coenzyme involved in various cellular processes. Here are some potential benefits based on preliminary research:

Prospects of increasing NAD+ by NMN

Potential health benefits in mouse models		Results of published human clinical trials
	Brain: improved brain function, protected from neurodegeneration, enhanced new myelin generation Lung: prevented pulmonary fibrosis, improved respiratory system function Liver: improved liver function, reduced hepatic steatosis, increased capacity to regenerate Heart: protected cardiomyocytes from injury caused by tachycardia Eye: exerted neuroprotective effects on photoreceptors Muscle: reduced atrophy, enhanced mitochondrial function and increased physical activity Vasculature: protected vasculature, increased capillary density, neovascularization, blood flow Inflammageing: improved immune cell function, reduced inflammation Skin: protected the skin from photodamage caused by UVB irradiation Reproduction: improved oocytes quality, restores fertility, increased the number of sperm		Safety: basically safe under the existing intervention dose and time Sleep quality: no significant improvement Muscle: prevented aging-related muscle dysfunctions and improving physical performance Ear: improved the right auditory ability of old men Cognition: no significant improvement Diabetes: increased muscle insulin sensitivity, insulin signaling, and remodeling in prediabetic women Telomere: increased telomere length Hypertension: significantly lowers blood pressure in mild hypertensive adults

In Humans

• Cellular Energy and Metabolism: By increasing NAD+ levels, NMN supplementation can potentially enhance cellular energy production and metabolism, leading to improved physiological functions and reduced age-related metabolic decline.
• Cognitive Function: Some research indicates that NMN may have neuroprotective effects, potentially improving cognitive function and reducing the risk of neurodegenerative diseases by maintaining neuronal health and resilience.
• Cardiovascular Health: NMN supplementation may offer cardiovascular benefits by improving blood flow and reducing the risk of age-related cardiovascular diseases, contributing to heart health and longevity.
• DNA Repair: Enhanced NAD+ levels through NMN supplementation can support DNA repair mechanisms, potentially reducing DNA damage and the risk of mutation, which are associated with aging and cancer.
• Insulin Sensitivity: NMN has been shown to improve insulin sensitivity, potentially reducing the risk of type 2 diabetes and metabolic syndrome, contributing to overall metabolic health.

Safety and Dosage

When considering NMN supplementation, it is crucial to understand the potential interactions and impacts of NMN. Here are some considerations based on current knowledge and research.

Dosage

Human studies have tested a range of doses, with some trials using up to 1,200 mg over 6 weeks. The longest study was about 250 mg over 24 weeks. However, the long-term safety, efficacy, and optimal dosage of NMN are still under investigation, and more comprehensive studies are needed to establish concrete guidelines for NMN supplementation.

David Sinclair takes 1000 mg/day NMN in the morning.

Safety

When it comes to NMN (Nicotinamide Mononucleotide) supplementation, safety is a primary concern, especially given the relatively early stage of human studies in this area. The current body of research, mostly comprising animal studies and limited human trials, suggests that NMN is generally well-tolerated at various dosages. However, there are several important safety considerations to keep in mind:

• Human Study Limitations: Most research on NMN has been conducted in animal models, primarily mice. While these studies are promising, human biology can respond differently, and the long-term effects of NMN in humans are still not fully understood.
• Dosage and Tolerance: The tolerability of NMN appears to be dose-dependent. Human studies have tested a range of doses, with some trials using up to 1,250 mg per day or 2,000 mg per day of the specialized NMN formulation MIB-626. These studies have generally reported good tolerability, but individual responses can vary.
• Interactions with Medications: The potential interactions between NMN and various medications are not yet fully understood. Individuals taking prescription medications, particularly those for chronic conditions, should consult with a healthcare provider before starting NMN supplementation.
• Long-term Safety: The long-term safety of NMN supplementation is an area that requires further research. While short-term studies have shown promising results, the effects of prolonged NMN use over years or decades are not yet known.
• Purity and Quality of Supplements: The market for NMN supplements varies widely in terms of product purity and quality. It is crucial to source NMN from reputable suppliers who provide third-party testing and quality assurance to ensure the product is free from contaminants and accurately labeled in terms of dosage.
• Population-Specific Effects: Different populations, such as the elderly, those with chronic illnesses, or those with specific genetic backgrounds, may respond differently to NMN supplementation. Tailored studies are needed to understand these variable responses better.

In summary, while NMN supplementation is an exciting area of research with potential health benefits, especially related to aging and metabolic health, it is essential to approach it with caution. Ongoing research and clinical trials will continue to inform safer usage guidelines and help identify the full spectrum of NMN's effects in humans.

Side Effects

Overall, there have been no serious side effects in humans clinical trials that have been due to the use of NMN. When taken at higher doses than intended, you could be facing side effects such as nausea, diarrhea, indigestion, and stomach discomfort. However, these are common side effects of supplements when taken in amounts that are too high.

Some individuals reported in NMN forums low energy and tiredness potentially caused by methyl donor deficiency (see next section). The side effects can occur from the beginning or after a longer period of use.

It is important to monitor for any adverse reactions, especially when starting supplementation or changing dosages.

Methyl Donor Deficiency

There is a theoretical concern that consuming NMN could deplete methyl groups in the body and might lead to a Methyl Donor Deficiency associated with symptoms such as low energy and tiredness. NMN is converted to NAD+ in the body, which can then be broken down into nicotinamide. Nicotinamide is then methylated by the liver to form N1-methylnicotinamide, which is excreted in the urine. This methylation process consumes a methyl group from S-adenosylmethionine (SAMe), the primary methyl donor in the body.

For this reason, some individuals who take NMN also supplement with methyl donors such as Trimethylglycine (TMG) or Vitamin B Complex to ensure that they are not depleting their body's supply of methyl groups. Some individuals take methyl donors as a precautionary measure, while others may begin supplementation after experiencing sleepiness attributed to NMN.

However, there is no clear evidence yet as clinical trials are lacking. While the biochemical pathway is known, the actual impact of NMN supplementation on the global status of methyl groups is not well-established in humans. It would likely require substantial NMN consumption coupled with an insufficient intake of dietary methyl donors to significantly affect these groups. There could be also a compensatory mechanisms in place slowing down the conversion of NMN to NAD+ or the methylation of nicotinamide if methyl groups were being depleted.

Types of NMN Administration

Nicotinamide Mononucleotide (NMN) can be administered in various forms, each with its unique considerations. Below is a breakdown of the common types of NMN administration:

• Oral Powder (Dissolved in Water): NMN powder can be dissolved in water and consumed as a drink. The benefit of this method, compared to capsules, is that the dosage can be easily adjusted, for example, reduced if side effects appear. In animal studies, particularly with mice, NMN is often mixed into the animals' drinking water.
• Oral Powder (Mixed with Food): NMN powder can also be mixed with food items such as yogurt. This method is considered oral ingestion, similar to dissolving it in water, and subjects the NMN to the digestive process. Mixing NMN with food can be convenient for those who prefer not to take it sublingually or in capsule form and may help mask any unpleasant taste of the NMN powder when dissolved in water. However, the effectiveness and bioavailability of NMN when mixed with food have not been extensively studied, and the presence of other food components and the acidic environment might potentially influence the stability and absorption of NMN.
• Capsule Form: NMN is encapsulated for easy consumption, offering a convenient and taste-neutral method. Like oral powder, capsules subject NMN to the digestive process. Capsule form is often used in clinical trials as it allows for precise dosing and is generally well-accepted by participants. It also enables the blinding of participants in placebo-controlled trials, maintaining the integrity of the study, as it is easier to make placebo capsules or tablets that are indistinguishable from the active ones.
• Sublingual Powder: This form of NMN is taken by placing the powder directly under the tongue, allowing it to dissolve and be absorbed through the mucous membranes in the mouth. The general guideline is to hold the substance under the tongue for approximately 1 to 5 minutes to allow for adequate absorption through the sublingual gland. Some individuals believe sublingual administration offers better bioavailability due to direct absorption into the bloodstream, bypassing the digestive system. However, while this method is promoted in many YouTube videos, there is no evidence of any positive or negative effects and there is currently no clinical study utilizing sublingual administration. Furthermore, this method is relatively inconvenient, especially for those who might find the taste of sublingual powder too strong.

Timing for Supplementation

Our body has a natural rhythm where NAD+ levels fluctuate throughout the day rather than remaining constant, closely tied to our circadian rhythms. NAD+ plays a crucial role in regulating our body's internal clock. The Sirt-1 gene, which is influenced by NAD+, signals our body when it's time to eat or sleep.

Dr. David Sinclair suggests to take NMN in the morning when the natural rise in NAD+ and Sirt-1 activity should happen. Taking NMN e.g. at night might disrupt the NAD+ cycle and potentially affecting the sleep or hunger. This can be especially beneficial for frequent travelers trying to adjust to a new time zone, as a morning dose of NMN can help reset the body's internal clock and reduce jet lag.

A recent RCT clinical trial investigated the effects of the time-dependent intake of NMN (250 mg/day) on older adults (≥ 65 years) over 12 weeks. Aging-induced insufficient physical activity and deterioration of physical function result in fatigue. This symptom frequently occurs among the elderly and has been complained by 27–50% of community-dwelling older adults in their daily life. Overall, NMN intake in the afternoon (in contrast to the morning) effectively improved lower limb function and reduced drowsiness in older adults. These findings suggest the potential of NMN in preventing loss of physical performance and improving fatigue in older adults.

Additionally, it's noteworthy that two MIB-626 trials utilized a twice per day administration regimen. This dosing schedule is significant because it could potentially offer more consistent NAD+ level support throughout the day, although the specific implications of this frequency in relation to circadian rhythms and overall efficacy remain an area for further research.

Stability and Storage

NMN powders are thought to degrade into NAD+ when left at room temperature. However, this may be true for pure NMN supplements, some supplements use NMN in a stabilized form. This form has been shown to be more stable thus resulting in less breakdown at room temperature.

Humidity or water can have negative effects on NMN and result in the degradation of NMN into NAD+. This fact is not disputed and thus NMN powder should be stored in a dry place in a resealable container.

In addition, scientists have tested NMN powders and found that these do not need to be kept in the refrigerator or freezer. The purity at 1 year when stored in a plastic bottle at room temperature was found to be 99.8%. Also a NMN manufacturer published NMN stability results when putting NMN into double pharmaceutical polyethylene bags. After 6 month under condition of 40℃ and 75% relative humidity the samples had > 99% purity.

However, it is advised if storing for the long-term (> 3 months), NMN supplements should be kept in the refrigerator to ensure its stability.

Overall, NMN powders are stable when stored at room temperature, especially when provided in a stabilized form. However, they need to be kept away from high-humidity environments as water can speed up the degradation of NMN. So if you plan to consume the powder immediately (< 1–2 months) you do not need to store it in the refrigerator but if stored for> 3 months it is best to store it in the refrigerator.

Always consult the manufacturer of you specific NMN supplements to obtain proper storage instructions for your product. If concerned, storing the NMN in the refrigerator does not have negative effects on the NMN and thus can be done.

NMN appears to be stable in water; in one study 93%–99% of NMN was maintained intact in drinking water at room temperature for 7–10 days.

Synergistic Supplements in Conjunction with NMN

While Nicotinamide Mononucleotide (NMN) itself is a promising compound in the realm of anti-aging and cellular health, its potential can be further enhanced when used in conjunction with other supplements. This section explores various nutraceuticals that may have synergistic effects when taken alongside NMN, potentially amplifying its benefits.

Stilbenes: Resveratrol and Pterostilbene

Stilbenes, particularly resveratrol and pterostilbene, are non-flavonoid phenolic compounds extensively studied for their anti-inflammatory, antioxidant properties, and their role in combating age-related disorders like diabetes and cancer. They are found naturally in grapes and berries, and studies have established their safety and bioavailability, with doses of resveratrol up to 5 grams and pterostilbene to 250 mg being well-tolerated.

Despite their potential, resveratrol and pterostilbene have shown lifespan extension only in certain preclinical models, with the results being context-dependent and subject to debate. Pterostilbene is particularly notable for its higher bioavailability (80%) compared to resveratrol (20%), and its efficacy in upregulating antioxidant enzymes like SOD and GR. This difference in bioavailability is critical in modulating the SIRT1 pathway, with co-administration of the two potentially maximizing their collective benefits.

Resveratrol's role in skin health, through its anti-angiogenic and wound-healing properties, is well-documented, while pterostilbene effectively mitigates inflammatory responses in various contexts.

The relationship between resveratrol and the SIRT1 pathway is a key focus in experimental models, especially in the context of dosage and supplementation. Although resveratrol has shown numerous health benefits, its direct activation of SIRT1 remains a subject of debate. Nonetheless, its indirect involvement in SIRT1 activation and its mimicry of caloric restriction effects suggest its potential as a metabolic modulator related to aging.

Resveratrol and pterostilbene's potential in conjunction with NMN supplementation is particularly promising. Their combined use can lead to increased NAD+ levels in the heart and skeletal muscle, more so than NMN alone. Resveratrol's ability to activate NMNAT1, thus increasing NAD+ levels and providing a substrate for SIRT1 activation, underscores the potential of these compounds in a targeted approach to delay or reverse aging signs. Their co-administration with NR has also shown a dose-dependent increase in NAD+ levels in acute kidney injury patients, further supporting their combined use in age-related therapies.

In summary, resveratrol and pterostilbene, especially when used in combination with NMN, represent a strategic orthomolecular approach to enhancing longevity and managing age-related diseases.

CoQ10

Coenzyme Q10 (CoQ10), also known as ubiquinol in its oxidized form, ubiquinone, is a crucial component in the mitochondrial electron transport chain. Its role in cellular energy production and as an antioxidant makes it integral to health, particularly in the context of neurodegenerative disorders, diabetes, cancer, fibrosis, and cardiovascular diseases. CoQ10 supplementation, especially in disease states, is aimed at restoring antioxidant activity to correct homeostatic imbalances.

CoQ10's cardiovascular protective qualities are well-established, with evidence showing its ability to improve hyperglycemia, hypertension, oxidative stress, and reduce the risk of cardiac events. Notably, endogenous synthesis of CoQ10 declines with age, and higher mitochondrial levels have been linked to increased longevity. This connection is particularly evident in skeletal muscle health in the elderly, where higher plasma CoQ10 content correlates with improved muscle integrity and reduced levels of inflammatory markers such as TNF-α, IL-6, and CRP.

The importance of CoQ10 extends to lipid metabolism, where it plays a key role in maintaining lipid integrity and preventing LDL oxidation, thereby offering protection against atherosclerosis. Replenishing declining CoQ10 levels in aging individuals is essential to mitigate the risk of age-related diseases and reduce the burden of oxidative stress. Studies have shown that CoQ10 supplementation, combined with dietary changes, can improve metabolic profiles in elderly men and women, reducing metabolic and cardiovascular risks.

In the context of chronic fatigue syndrome (CFS), which shares several characteristics with aging such as inflammation and oxidative stress, CoQ10 and NAD+ supplementation have demonstrated synergistic effects. These supplements have been shown to decrease maximum heart rate post-exercise and improve fatigue symptoms, as well as enhance levels of NAD+/NADH, CoQ10, ATP, citrate synthase, and lipoperoxides.

The antioxidant, anti-inflammatory, and age-mitigating effects of CoQ10 position it as a valuable supplement in an orthomolecular approach to combat the biological process of aging. This is especially true when considering its supportive role in enhancing NAD+ levels. However, further research is needed to fully elucidate the synergistic benefits of combining NAD+ precursors with CoQ10 supplementation in aging and age-related diseases.

Trimethylglycine (TMG)

Trimethylglycine (TMG), also known as betaine, was initially derived from the beetroot plant and is recognized for its osmoprotectant and anti-inflammatory properties. As a primary methyl group donor, TMG plays a significant role in DNA methylation processes, alongside other compounds like methionine and choline. The rate of DNA methylation is closely linked to the availability of these methyl donors. TMG also acts to suppress various inflammatory expression profiles, including TNF-α, COX2, and NF-kB activity.

The role of TMG extends to combating age-related pathologies. It does so by supporting optimal lipid and glucose metabolism, inhibiting inflammatory transcription processes, and reducing cellular ER stress. One of the notable aspects of TMG's function is its influence on the methylation process, crucial for epigenetic regulation and genome stability, which are integral to healthy aging.

A key consideration in the context of NAD+ supplementation is the impact on TMG levels. The degradation of NAD+ precursors, particularly nicotinamide (NAM), demands a higher consumption of TMG compared to choline, potentially depleting the available pool of methyl donors. This elevated consumption of TMG during NAM degradation underscores the importance of supplementing with methyl donors when administering NAD+ precursors, especially NAM, to maintain balanced methylation.

However, the specific effects of NMN or direct NAD+ conversion on methylation levels have yet to be thoroughly investigated. Therefore, concurrent supplementation of NMN, NAD+, or other NAD+ precursors along with TMG could be a strategic approach to prevent a decline in TMG levels. This co-supplementation may ensure the maintenance of proper methylation health and function, thereby supporting overall well-being and potentially mitigating age-related decline.

Flavonoids: Quercetin, Fisetin, Luteolin/Luteolinidin, and Apigenin

Flavonoids such as fisetin, quercetin, luteolin/luteolinidin, and apigenin have demonstrated significant health benefits, including potent senolytic activity.

Fisetin and quercetin are known for their anti-cancer properties, particularly in inducing calcium-induced tumor apoptosis and improving cancer-related inflammatory profiles. Fisetin, in particular, has shown strong senolytic effects in older and progeroid mice models, as well as in murine and human adipose tissues, contributing to improved lifespan and tissue homeostasis. Its safety and efficacy are being investigated in Phase 2 clinical trials focusing on reducing inflammation and improving walking speed in frail elderly individuals (NCT03675724, NCT03430037). Fisetin also interacts with the NAD+/NADH age-related pathway, notably through SIRT1 activation, suggesting potential geroprotective effects in the context of NAD+/SIRT1/CD38 pathways, although more research is needed to establish concrete effects on longevity.

Quercetin, structurally similar to fisetin, is also recognized as a senolytic agent with benefits in cardiovascular disease, neurodegeneration, inflammation, oxidative stress, cancer, and diabetes management. It is considered a geroprotective agent in in vitro models of premature aging. Quercetin contributes to the modulation of the NAD+/SIRT1/CD38 axis by altering the NAD+/NADH ratio, activating SIRT1, and inhibiting CD38, thereby impacting metabolic disorders.

Luteolin and its derivative luteolinidin have shown anti-inflammatory effects, particularly in skin aging, skin diseases, and cognitive functions. They are implicated in the CD38 mechanism, acting as potent inhibitors and leading to an increase in available NAD+ levels. Their potential in clearing cellular senescence, especially when used alongside NAD+ supporting compounds, highlights their role in longevity promotion.

Apigenin, derived from parsley and chamomile, exhibits strong anti-inflammatory, antioxidant, and anti-carcinogenic properties. It reduces inflammatory mediators like COX2, IL6, and TNF-α, and upregulates antioxidant enzymes such as SOD, GPX, and GR^{[10.1080/10942912.2016.1207188]}. Apigenin's anti-cancer activity is evident in its ability to downregulate key cancer pathways and sensitize tumor cells to chemotherapy. It also attenuates metabolic complications and possesses anti-obesity effects. Additionally, apigenin improves vascular endothelial function and structure, counteracting age-related changes due to oxidative stress.

In the context of NAD+ supplementation, apigenin’s involvement with the SIRT1, NAD+, and CD38 axis is particularly notable. It enhances endogenous NAD+ levels by inhibiting CD38 and increasing the activation ratio of SIRT1 and NAD+/NADH, thereby reducing cellular senescence due to oxidative stress. This strong inhibition of CD38 by apigenin makes it an integral part of strategies aimed at restoring age-related depletion of NAD+ levels, enhancing the effectiveness of NMN supplementation and overall geroprotective strategies.

Carotenoids: Astaxanthin and Lycopene

Carotenoids like astaxanthin and lycopene are renowned for their antioxidant and anti-inflammatory properties, playing a significant role in health and longevity (Figure 2).

Astaxanthin is a powerful antioxidant carotenoid known for its ability to mitigate reactive oxygen species (ROS) and support mitochondrial integrity. It has shown remarkable efficacy in activating SIRT1, which contributes to its longevity-promoting effects:

• Neuroprotection: Astaxanthin has been demonstrated in vivo to alleviate oxidative stress in brain injury, upregulating Nrf2 and SIRT1 expression while decreasing pro-apoptotic factors, thus potentially reducing the risk of neuronal death.
• Cardiac and Fibrotic Protection: It ameliorates the effects of a high-fat diet on cardiac and fibrotic damage through SIRT1 upregulation, inhibition of inflammatory cell mobility, and reduced collagen deposition, leading to less fibrosis post-injury.
• Renal Tissue Protection: Astaxanthin also protects renal tissue post-injury through SIRT1 upregulation.
• Boosting NAD+ Levels: Notably, a study combining NMN, astaxanthin, and blood orange extract in aging zebrafish demonstrated an enhanced ability to raise NAD+ levels, surpassing combinations of NR with astaxanthin or pterostilbene^{[10.1093/cdn/nzac047.054]}. This finding suggests astaxanthin's potential in NAD+ boosting strategies and warrants further research on effective dosages and combinations in humans.

Lycopene is another carotenoid with significant antioxidant and anti-inflammatory effects. It is known for improving various age-related conditions:

• Physical Performance and Skin Aging: Supplementation with lycopene has been shown to enhance physical performance, combat osteoporosis, and improve skin aging, owing to its antioxidant properties.
• Muscle Angiogenesis and Insulin Resistance: Lycopene activates SIRT1, which aids in muscle angiogenesis and the reversal of insulin resistance in age-related vascular decline.
• Combination Therapy with NMN: In models of D-galactose-induced aging, a combination of NMN and lycopene showed superior results compared to NMN alone. It enhanced antioxidant enzyme activities, demonstrated senolytic abilities, upregulated Nrf2, and improved cognition in vivo.

Both astaxanthin and lycopene exhibit promising roles in geroprotective strategies, particularly in enhancing NAD+ levels and SIRT1 activation. Their combined use with NMN or other NAD+ precursors could potentially maximize the efficacy of interventions aimed at boosting NAD+ availability and combating age-related decline.

Curcumin

Curcumin, a compound derived from turmeric, is gaining recognition as a potent senolytic agent, similar to the flavonoids previously discussed (Figure 2). Its effects on aging and age-related pathologies are significant and multifaceted:

• Senescence and Longevity Pathways: Curcumin has shown promising results in improving cellular senescence associated with aging. It also modulates key longevity pathways, such as mTOR and FoxO, indicating its potential in extending healthy lifespan.
• Neurodegenerative Diseases: In the realm of neurodegeneration, curcumin has been found to upregulate SIRT1, a protein linked to aging and cellular health. This effect suggests its potential in mitigating neurodegenerative disorders.
• Cardiovascular Health: Curcumin's impact on cardiovascular health is highlighted by its ability to activate AMPK, another significant pathway in aging and metabolic regulation.
• Anti-cancer Properties: Experimental models of head and neck squamous cell carcinoma have shown that curcumin can inhibit cancer cell migration and angiogenesis, underscoring its anti-cancer potential.
• Physical Performance: A six-week supplementation with curcumin in human runners has led to improvements in antioxidant capacity and aerobic performance. This benefit is accompanied by an increase in SIRT3, a mitochondrial protein linked to energy metabolism.

The relationship between curcumin and sirtuins, particularly in the context of NAD+ boosting, is a promising area of research. However, the effectiveness of combining curcumin with NAD+ enhancing supplements needs to be explored further in clinical trials. Such studies would help establish whether curcumin can augment the benefits of NAD+ precursors, potentially leading to more effective anti-aging therapies.

Alpha-Ketoglutarate

Alpha-ketoglutarate (aKG) is a critical metabolic intermediate in the Krebs cycle, playing an important role in the aging process. Its involvement in various longevity-related mechanisms makes it a significant compound in geroprotection and anti-aging research.

• Inhibition of the TOR Pathway: aKG is known to inhibit the TOR pathway, akin to the effects of caloric restriction. This inhibition, coupled with its ability to hinder ATP synthase, has been shown to extend the lifespan in C. elegans.
• Metabolic and Antioxidant Benefits: Providing both metabolic and antioxidant benefits, aKG has been demonstrated to extend lifespan. This effect is evident not only in model organisms but also in mice. Recent pilot clinical trials have indicated that Rejuvant, a novel formulation of aKG, effectively reduces biological age in humans.
• Interplay with NAD+: The relationship between aKG and NAD+, a vital coenzyme for cellular health and aging, remains under-researched. Future studies should explore this interaction to enhance our understanding of how aKG can be utilized in longevity therapies.

The potential of aKG in anti-aging strategies is promising, but more research is necessary to fully understand its interactions, particularly with NAD+.

Epigallocatechin Gallate

The polyphenol epigallocatechin gallate (EGCG; Figure 2), predominantly found in green tea, is renowned for its neuroprotective, antioxidant, and anti-inflammatory properties. Current research is investigating its role in alleviating a variety of diseases. EGCG's interaction with aging and longevity pathways is particularly noteworthy.

• Lifespan Extension: EGCG has been shown to increase lifespan in response to oxidative stress, as evidenced by studies in rats demonstrating enhanced longevity under such conditions.
• SIRT1 Modulation: The effect of EGCG on SIRT1, a crucial protein in aging and metabolism, appears to vary depending on the context. Some studies have observed an upregulation of SIRT1 following EGCG administration, while others have reported a downregulation, especially in cancer cells. This suggests that EGCG's impact on SIRT1 may differ based on specific biological factors and the need for upregulation of longevity pathways in response to oxidative stress.
• NAD+/NADH Ratio Effects: The influence of EGCG on the NAD+/NADH ratio, vital for cellular metabolism and aging, requires further investigation. Understanding how EGCG affects this ratio is essential for comprehending its potential as an anti-aging agent and its role in cellular health maintenance.

The diverse effects of EGCG on SIRT1 and the NAD+/NADH ratio underline the importance of more detailed research to clarify its mechanisms of action, particularly regarding longevity and age-related diseases.

Clinical Trials

Starting in 2020, with the assessment of the safety of a single dose administration of NMN, there have been around 10 randomized controlled trials (RCTs) exploring the compound's effects in various contexts. The trials have varied in duration, with the longest running for 12 weeks. In terms of dosage, they have explored a range of quantities, with the highest being 1,250 mg of NMN per day and 2,000 mg (2 g) of MIB-626, a specific formulation of NMN, per day. The following table provides a comprehensive overview of these trials, detailing their design, participant demographics, dosages, and key findings:

Clinical Trials of NMN

Clinical Trial	Design (dosage is per day, 2x means twice per day)	Participants	Outcome
2020, Effect of oral administration of nicotinamide mononucleotide on clinical parameters and nicotinamide metabolite levels in healthy Japanese men	singe admission up to 500 mg	10 healthy men age 40-60	admission was safe and well-tolerated
2021, Nicotinamide mononucleotide increases muscle insulin sensitivity in prediabetic women	RCT, 10 weeks placebo (n=12) 250 mg (n=13)	25 postmenopausal women with prediabetes overweight or obese (BMI 25.3 - 39.1) age 56-66	increase in skeletal muscle insulin signaling, insulin sensitivity, and muscle remodeling improvement in muscle insulin sensitivity is clinically relevant and is similar to the improvement observed after ~10% weight loss
2021, Nicotinamide mononucleotide supplementation enhances aerobic capacity in amateur runners: a randomized, double-blind study	RCT, 6 weeks placebo (n=12) 300 mg (n=12) 600 mg (n=12) 1200 mg (n=12)	48 young and middle-aged recreationally trained runners age 35 average	The combination of NMN supplementation and exercise further improves ventilatory threshold even among healthy young and middle-aged people. The improvement of aerobic capacity is in a dosage-dependent, large dosage of NMN with exercise has better effects. The improvement is muscle, not cardiac, related.
2021, The Impacts of Short-Term NMN Supplementation on Serum Metabolism, Fecal Microbiota, and Telomere Length in Pre-Aging Phase NMN.com article	90 days 300 mg in warm water	8 healthy men age 45–60	* NMN doubles the telomere length of humans over a 90-day period of time.
2022, Safety evaluation of β-nicotinamide mononucleotide oral administration in healthy adult men and women	RCT, 4 weeks placebo (n=15) 1250 mg (n=16)	31 healthy adult men and women age 20–65	Oral administration of 1250 mg of NMN, when administered once daily for up to 4 weeks, was safe and well-tolerated in healthy adult men and women. Oral administration of NMN in humans has a low adverse effect on renal function. Results indicate that NMN can be administered orally to humans at doses 1250 mg once daily for up to 4 weeks without causing hepatotoxicity and vasodilative flushing, and is believed to have a higher upper tolerable limit compared to NAM and NA.
2022, Effect of 12-Week Intake of Nicotinamide Mononucleotide on Sleep Quality, Fatigue, and Physical Performance in Older Japanese Adults: A Randomized, Double-Blind Placebo-Controlled Study	RCT, 12 weeks placebo, before 12 pm placebo, after 6 pm 250 mg, before 12 pm 250 mg, after 6 pm	108 older adults age ≥ 65	NMN intake in the afternoon is more effective in improving lower limb function and reducing drowsiness in older adults.
2022, Chronic nicotinamide mononucleotide supplementation elevates blood nicotinamide adenine dinucleotide levels and alters muscle function in healthy older men	RCT, 12 weeks placebo (n=10) 250 mg (n=10)	20 healthy male age ≥ 65 BMI 22–28 nonsmokers	250 mg of NMN per day for 12 weeks significantly increased NAD+ blood levels in healthy males older than 65. The supplementation regimen improves walking speed and grip strength in the aged men. These findings suggest NMN supplementation may be used to ameliorate age-related muscle deterioration.
2022, A Multicentre, Randomised, Double Blind, Parallel Design, Placebo Controlled Study to Evaluate the Efficacy and Safety of Uthever (NMN Supplement), an Orally Administered Supplementation in Middle Aged and Older Adults	RCT, 60 days placebo (n=31) 300 mg (n=31)	66 healthy subjects age 40-65	NAD+/NADH concentration in serum increase by 11.3% after 30 days, 38% after 60 days
2022, Nicotinamide Mononucleotide Is Safely Metabolized and Significantly Reduces Blood Triglyceride Levels in Healthy Individuals	single intravenous administration 300 mg	10 healthy adults age 20-70	300 mg intravenous NMN administration is tolerated by humans significantly increased blood NAD+ levels
2023, The efficacy and safety of β-nicotinamide mononucleotide (NMN) supplementation in healthy middle-aged adults: a randomized, multicenter, double-blind, placebo-controlled, parallel-group, dose-dependent clinical trial	RCT, 8.5 weeks (60 days) placebo (n=20) 300 mg (n=20) 600 mg (n=20) 900 mg (n=20)	healthy males and females age 40-65 BMI between 18.5 and 35	Oral administration of NMN up to 900 mg/day for 60 days was safe and well tolerated blood NAD concentration was significantly and dose-dependently increased significant improvement of six-minute walking test, blood biological age, and SF-36 scores 900 mg/day oral dose did not give significantly better efficacy than 600 mg/day dose
2023, MIB-626, an Oral Formulation of a Microcrystalline Unique Polymorph of β-Nicotinamide Mononucleotide, Increases Circulating Nicotinamide Adenine Dinucleotide and its Metabolome in Middle-Aged and Older Adults	RCT, 2 weeks 1000 mg MIB-626 2x1000 mg MIB-626 placebo	32 overweight or obese adults age 55-80	MIB-626 was well tolerated Blood NMN concentrations significantly higher in treated groups compared to placebo Substantial dose-related increases in blood NAD levels and its metabolome Changes in NMN or NAD levels not related to sex, BMI, or age Very little unmodified NMN excreted in urine Facilitates design of efficacy trials in disease conditions
2023, Nicotinamide Adenine Dinucleotide Augmentation in Overweight or Obese Middle-Aged and Older Adults: A Physiologic Study	RCT, 4 weeks 2x500 mg/day MIB-626 placebo	30 overweight or obese adults age ≥ 45	MIB-626 treatment increased circulating NAD and metabolites No significant change in muscle strength, muscle fatigability, aerobic capacity, and stair-climbing power Significant reduction in body weight, diastolic blood pressure, total LDL, and non-HDL cholesterol Insulin sensitivity and hepatic and intra-abdominal fat unchanged Adverse events similar between groups Provides rationale for larger trials on NAD augmentation for cardiometabolic outcomes in older adults
2023, Nicotinamide adenine dinucleotide metabolism and arterial stiffness after long-term nicotinamide mononucleotide supplementation: a randomized, double-blind, placebo-controlled trial	RCT, 12 weeks, capsules placebo (n=17) 2x125 mg (n=17)	34 healthy male and female age 40-59	250 mg of NMN for 12 weeks does not significantly reduce artery stiffness — a risk factor for cardiovascular disease, dementia, and death — in healthy middle-aged adults. However, NMN reduces artery stiffness in individuals with high blood-glucose and body mass index (weight/height). Blood vessel biological aging is reversed by 2 years with NMN treatment.
2023, Effects of nicotinamide mononucleotide on older patients with diabetes and impaired physical performance: A prospective, placebo-controlled, double-blind study	RCT, 24-week placebo 250 mg	male patients with diabetes reduced grip strength (<26 kg) or walking speed (<1.0 m/s) age ≥ 65	NMN was tolerable without any severe adverse events NMN did not improve grip strength and walking speed Improved prevalence of frailty in the NMN group (P = 0.066) Different changes in central retinal thickness between the two groups (P = 0.051)
2023, NAD+ exhaustion by CD38 upregulation contributes to blood pressure elevation and vascular damage in hypertension NMN.com article	6 weeks, lifestyle modifications no NMN (n=10) 800 mg (n=9)	19 mild hypertensive adults age 18-80	Supplementing hypertension patients with 800 mg of oral NMN per day for six weeks significantly lowers their blood pressure. Hypertension patients display significantly lower blood cell NAD+ levels, and taking NMN increases their blood cell NAD+ levels by ~43%. Adults with hypertension have cells lining blood vessels — endothelial cells — with elevated concentrations of the NAD+ consuming enzyme CD38, which partially explains their lower NAD+ levels.
2022, Oral Administration of Nicotinamide Mononucleotide Is Safe and Efficiently Increases Blood Nicotinamide Adenine Dinucleotide Levels in Healthy Subjects NMN.om article
2023, Nicotinamide mononucleotide (NMN) intake increases plasma NMN and insulin levels in healthy subjects

See also

• Nicotinamide Adenine Dinucleotide (NAD+)
• NAD+ Boosters
• NAD+ Precursor
• NMN Manufacturer
• Wikipedia - Nicotinamide mononucleotide

Todo

• https://www.nmn.com/news/nmn-tablet-blood-nad-levels-humans
• https://link.springer.com/article/10.1007/s13668-023-00475-y
• https://www.lifespan.io/topic/nmn-nicotinamide-mononucleotide-benefits-side-effects/
• https://novoslabs.com/frequently-asked-questions/nmn-nicotinamide-mononucleotide/can-you-take-nmn-if-you-have-a-mthfr-mutation-or-suffer-from-reduced-methylation/
• https://ajtm.journals.publicknowledgeproject.org/index.php/ajtm/article/view/2535
• https://www.nature.com/articles/s41598-018-30792-0
• https://www.nmn.com/news/new-study-shows-nmn-rejuvenates-stem-cells-and-mitochondria-by-activating-longevity-protein

2022, Nicotinamide Mononucleotide Supplementation Improves Mitochondrial Dysfunction and Rescues Cellular Senescence by NAD⁺/Sirt3 Pathway in Mesenchymal Stem Cells

• Slc12a8
  • 2021, NAD⁺ metabolism and its roles in cellular processes during ageing
  • 2022, Slc12a8 in the lateral hypothalamus maintains energy metabolism and skeletal muscle functions during aging
  • https://patents.google.com/patent/US11564936B2/