Nicotinamide adenine dinucleotide (NAD+) is an extremely important chemical in our energy metabolism, such as when we oxidize fatty acids to create energy. On the other hand, scientists discovered nicotinamide mononucleotide (NMN) in 1963 as a precursor of NAD+ and have been shown to increase its levels. NMN occurs naturally in numerous plant and animal food sources such as broccoli or shrimp.
NMN is an important chemical in the human body that helps maintain NAD+ levels. A crucial molecule for DNA repair and energy metabolism, among other things, and is found in all living cells.
Although NMN has been shown to have numerous benefits, most have been demonstrated in rodent studies, and optimal dosing and applicability to humans are still being researched.
NMN is not considered toxic nor expected to have side effects. However, any NMN supplementation may be adulterated.
The best way to ensure adequate NMN intake is through consuming fruits and vegetables such as cabbage and edamame (immature soybean) or from animal sources such as beef and shrimp.
If you decide to take NMN supplements in addition to consuming NMN-rich foods, make sure they are reliable.
What is NMN?
NMN is a precursor to NAD+ and has been shown to participate in more than half of all physiological processes in helping activate countless enzymes related to different disease processes, DNA repair, or age-associated deterioration. The body synthesizes NMN from Vitamin B3; however, this process is comparatively slow, so it produces a bottleneck for NAD+ metabolism. Thus, it also makes logical sense that NMN supplementation would benefit and increase NAD+ levels.
NMN vs. NAD+: what's the difference?
Simply put, there would be no life without NAD+. NAD+ is found in all living cells and is mainly tasked with transporting electrons in the process of energy generation. Because NAD+ is so important, not only is it synthesized directly from tryptophan or aspartic acid, but it is also recycled. NMN comes into play during this recycling and plays a role in the most crucial step of this salvage pathway. Thus, NMN helps prevent NAD+ levels from declining and ensures the proper functioning of this crucial salvage pathway.
There has been incredible interest in NMN, as NAD+ is necessary for all life. NAD+ levels decline with age, and enhancing NAD+ in worms and flies has been shown to extend life. Additionally, NMN supplementation has been shown to have exceptional therapeutic effects on various metabolic processes. From an insulin and diabetes standpoint, NMN has been shown to ameliorate impairments in insulin secretion and improve insulin action. Furthermore, NMN has been shown to protect the heart from ischemia/reperfusion, such as may happen during a heart attack. NMN has also been shown to improve mitochondrial and cognitive function in Alzheimer’s disease models in mice, improve hearing loss, maintain muscle stem cell function, and prevent DNA damage and hepatocellular carcinoma formation.
Where can you find NMN?
NMN is naturally occurring and found in many foods, such as healthy vegetables, nutrient-dense fruits, and some animal-based foods. Furthermore, due to increased interest in and associated scientific studies of NMN, there are now countless supplements containing NMN.
However, as not all supplements are properly tested nor require FDA or a similar regulatory authority’s approval, the onus is on the consumer to ensure that the supplement is not adulterated. The FDA publishes a list of adulterated supplements, and it includes some NMN supplements.
The company Hello100, for instance, provides NMN supplements in their bioavailable form, tested and approved by Independent Labs
Foods rich in NMN
NMN is found mainly in vegetables such as cabbage, broccoli, and cucumbers and fruit such as avocado and tomato:
|Food||NMN Per 100g|
|Tomato (medium-average sized)||0.28 mg|
|Ran beef||0.06–0.42 mg|
Does NMN have side effects?
NMN is well tolerated and without noticeable toxicity or serious side effects in countless rodent studies. A single dose of 100-500 mg of NMN was not found to have any side effects in healthy adults, contrary to other metabolites in the NAD+ metabolism, such as NA and nicotinamide (NAM), which may cause liver damage and painful flushing.
Can NMN cause cancer?
There has been concern about whether NMN causes or promotes cancer by enhancing NAD+ in cancerous cells and possibly conferring some immunity from some types of chemotherapy. However, several studies demonstrated that NMN does not prevent the formation of lung cancer, retrain tumor growth, or promote tumor growth in mice models. So, at least, NMN has no negative cancerous effects and, at best, may have some protective effects.
How can you increase NAD+ levels naturally?
One of the best ways to increase NAD+ levels naturally is regular aerobic exercise. Exercise training increases nicotinamide phosphoribosyltransferase (NAMPT), the bottleneck enzyme in the salvage pathway for NAD+, where NMN comes into play. Interestingly, in the same context, a mouse obesity model study demonstrated that nine weeks of exercise and 18-days of NMN injections had similar benefits on metabolic dysfunction and hepatic fat metabolism. Furthermore, caloric restriction has also been shown to improve lifespan and increase NAD+ levels, particularly in the context of a healthy diet rich in the forms of vitamin B3 or tryptophan. Finally, ensuring sufficient sleep in an appropriate circadian rhythm also has been shown to ensure high NAD+ levels.
Best way to take NMN: Supplements or diet
NMN doses of up to 500 mg have been utilized in various studies on humans. However, there seem to be different optimal doses based on the intended outcome elucidated by different studies. As with most other metabolic processes, eating a well-balanced and healthy diet with hydrating fruits, delicious and nutrient-dense vegetables, and protein from animal sources is the best way to ensure you’re getting sufficient amounts of NMN. Increasing your daily intake of NMN supplements can also be appropriate, granted you trust the supplement source, and it has demonstrated its applicable purity and potency.
Please be aware that from the fall of 2022 NMN is under an investigation as a potential new drug by the FDA. That puts the legality of the product as a dietary supplement in question. It’s a complicated situation that’s not yet solved. However, it is important to note that since we are not a manufacturer or retailer, we do not take any responsibility for the availability of the product as a dietary supplement after having lost its dietary ingredient status.
- NIH. Nicotinamide mononucleotide supplementation enhances aerobic capacity in amateur runners: a randomized, double-blind study.
- NIH. NAD+ Intermediates: The Biology and Therapeutic Potential of NMN and NR.
- NIH. NMN does not protect the ovarian reserve from cancer treatments.
- NIH. Healthy Lifestyle Recommendations: Do the Beneficial Effects Originate from NAD+ Amount at the Cellular Level?
- NIH. Long-Term Administration of Nicotinamide Mononucleotide Mitigates Age-Associated Physiological Decline in Mice.