
NMN supplements are being touted as a way to help your body turn back the biological clock, but how much should you be taking?
Wouldn’t we all love to turn the body clock back a few notches? Well, now it seems we can, or at least slow the clock down, thanks to a growing number of supplements that increase the supply of NAD+ in the body.
While each of these supplements make bold statements, do they actually have any benefits, and what are the potential side effects?
What is NMN?
NMN, or nicotinamide mononucleotide, is a precursor of an essential molecule called NAD+. Research has shown that not only does NAD+ provide the energy we need to function, grow and repair, but it could also be critical in stemming the process of aging.
Wonderfeel®, a biosciences company spearheading NMN research, has moved that longevity needle forward with their patented Youngr™ NMN formula. Wonderfeel’s Chief Medical Officer, Harvard MD, and biomedical inventor, Professor Andrew Salzman explains why people need to pay attention to NAD+.
“Despite all healthcare advances over the last 100 years, what’s the limiting factor?” asks Dr Salzman. “Fundamentally, the evolutionary problem is that our NAD levels drop as we age. And it starts in our 30s and 40s.”
As we grow older, our bodies naturally become more susceptible to various diseases, heart conditions, obesity and many other problems. This susceptibility aligns with the decline in NMN and NAD+ levels documented by research; in fact, by the age of 50, we only have half the amount of NMN that we did in our 20s.
NAD+ is consumed by key proteins and enzymes that play a critical role in repairing damage to our DNA, fuelling our cells and keeping our metabolic and immune systems ticking over nicely. But it is more than maintaining our systems – NAD+ could hold the key to preventing age-related decline.
If we can keep NAD+ levels reasonably high, we could slow down the aging process and even, in some situations, start to wind it back a little. This is where NMN comes into play. It is an NAD+ precursor that the body uses to restore more youthful levels of NAD+.
Benefits of NMN supplements

Research on NMN is actively ongoing and includes both rodent and human trials. Studies so far have hinted at several NMN benefits, including:
1. Lowers obesity risk
Increased levels of NMN stimulate the metabolic system, which enhances the body’s ability to turn food into energy and can be a tool in reducing the risk of obesity. However, this should happen alongside an active lifestyle and healthy diet.
2. Reduces the risk of heart disease
The heart works 24/7 throughout your life without a breather. It produces huge amounts of energy and will need all the NAD+ it can get.
3. Improves metabolic disorders
Early research is finding that NAD precursors may help reduce body weight, counteract the effects of high-fat diets and improve energy. A small trial looked at the effect of NMN on women with prediabetes and found their muscles’ ability to process sugar improved.
4. Improves fitness and muscle endurance
Our bones and muscles consume glucose and fatty acids in order to continue functioning. NAD+ helps them to be metabolised into the system. Without it, everything slows down and muscle endurance declines.
A recent trial on amateur runners also found that NMN increases human aerobic capacity. Researchers theorise that this is due to enhanced oxygen use in the skeletal muscle.
5. Improves cognitive function
Models of Alzheimer’s disease showed improved cognition and memory with NMN supplementation; this is most likely due to NAD+’s ability to improve many critical functions in the brain.
6. Improves symptoms of serious disease
Researchers are also exploring the benefits of increased NAD levels on high blood pressure, liver health and diabetes.
Inside the body, NAD+ produced by NMN supplements stimulates the activity of mitochondria, microscopic organelles that are vital to our metabolism. The powerhouses of the cells, mitochondria transform glucose and oxygen into cellular energy – without them, cells would lack energy and die.
NAD+ also activates sirtuins, a family of proteins that repair our DNA and regulate cellular homeostasis. Each time our cells divide, the caps on the ends of our DNA strands become slightly shorter; this fraying and shortening damage our DNA, but sirtuins reduce this process by stabilizing these caps, or telomeres. Studies in mice show that feeding them NMN can elongate telomeres, offsetting the risk of DNA damage.
Interestingly, sirtuins are NAD-dependent, which means they can’t function properly without it. However, as NAD production increases, so too does sirtuin activity.
Side effects of NMN supplements
When taken at high levels, some NAD-boosting supplements have been reported to have side effects such as nausea, diarrhea, flushing, stomach discomfort and indigestion.
However, people involved in studies with NMN supplements have reported no significant side effects at dosages up to 1,200mg.
Harvard Professor David Sinclair, speaking on the Joe Rogan podcast, claimed to take as much as one gram of NMN every day with only an occasional upset stomach to show for his pains, but, of course, he is speaking from his personal experience.
In terms of clinical trials, a human study in Japan found no ill effects at doses up to 500mg, while another study into endurance found no issues at dosages of up to 1200mg. One of the most recent clinical trials administered NMN supplements in placebo, 300, 600, and 900mg doses, with no signs of toxicity at any amount.
Research is still ongoing, but there are not currently any significant safety fears over NMN supplements. And as Dr Sinclair puts it: “Human studies with NAD boosters are ongoing and so far, there has been no toxicity, not even a hint of it.”
Biggest safety concern
The biggest safety concern is the number of cheap and fake imitations. Products that make the same claims are available at a fraction of the price. Many of these are not pure NMN. Instead, they have been bulked out with other compounds – this raises the specter of safety issues, especially if the manufacturer has not been clear about what exactly is in there.
This is particularly true if a company manufactures its NMN in non cGMP-certified facilities, with a greater potential for impurities. Remember that in the US, NMN is considered a dietary supplement and thus has no requirement for being proven safe and effective before coming to market.
Instead, NMN supplements are subject to postmarket enforcement by the Food and Drug Administration – this means that consumers need to be cautious about the brands they trust.
Understanding the manufacturing process can be helpful as well. There are three common methods for manufacturing NMN:
Chemical synthesis
Labor-intensive and expensive, this method creates a high yield and allows for careful control of starting materials, though none are sourced from biological systems. It uses environmentally-damaging solvents, impurities, and byproducts in the finished product can be difficult to remove.
Enzymatic synthesis
This option is expensive, but produces a higher yield and very high purity. It’s considered a green preparation method for the production of NMN.
Fermented biosynthesis
This method isn’t well-suited to commercial production because it has a low yield, though high quality.
To be safe, look for recognized brands that are transparent about their production methods and those that have been independently approved.
Wonderfeel is a good example – the company manufactures its supplement in cGMP-certified facilities via enzymatic synthesis. Its starting material for the process is cloned from a food-grade yeast called Kluyveromyces marxianus, which is “generally considered as safe” by the FDA and has “qualified presumption of safety” from the European Food Safety Authority.
Plus, the company has over three years’ worth of data to prove the stability and purity of its finished product, along with certifications to confirm that no irradiation or ETO-sterilisation are used during manufacturing.
Rather than being concerned about safety, though, many people will be focusing more on cost and understanding how much NMN is necessary to achieve the desired effect. Because NMN is so difficult to manufacture, products tend to be fairly expensive. You will therefore be keen to ensure you take as much as you need and no more.
Ideal dosage
While no side effects have been reported, there is still no consensus on the right amount of NMN. Many studies to date have looked at low doses. However, longevity experts like Drs Sinclair and Salzman suspected that higher doses would prove more beneficial. The 2022 clinical study assessing results of placebo, 300, 600, and 900mg doses found the greatest efficacy in the 900mg group.
The endurance trial investigating doses of 300, 600, and 1,200mg daily found the biggest impact in the medium and high groups, which averages a 900mg daily dose.
Supplement providers will often recommend correct levels based on their research and observations. Some will suggest varying the doses by weight with higher doses recommended for heavier people.
NMN supplements will often come in sizes between 100mg and 500mg with doses of between one and six tablets recommended. Check the manufacturer’s label to see how much they recommend taking.
For example, Wonderfeel recommends two capsules of its Youngr NMN – a daily amount of 900mg. The company’s recommendation is specific to its own formula, which also includes a trio of antioxidants for enhanced sirtuin activity. Antioxidants also help shield the cell from oxidant stress to more effectively deliver NMN.
Clinical understanding of NMN supplements is still evolving, with each trial and piece of research enhancing our knowledge further. From what has been observed in the studies conducted, it seems that this approach provides actual advantages in relation to health and lifespan, with minimal occurrences of side effects.