In 2013, research published by Dr David Sinclair demonstranted that short term supplementation with Nicotinamide MonoNucleotide (NMN) reversed many aspects of aging, making the cells of old mice resemble those of much younger mice, and greatly improving their health (8).
The quotes below are directly from that research:
NMN was able to mitigate most age-associated physiological declines in mice”
“treatment of old mice with NMN reversed all of these biochemical aspects of aging”
Since that landmark 2013 study, dozens of others have been published investigating the efficacy of supplementation with NMN in treatment and prevention of a wide range of disease including cancer, cardiovascular disease, diabetes, Alzheimers, Parkinsons, and more (5,6,7,9,10,11,13,14,15,16).
According to Dr Sinclair:
enhancing NAD+ biosynthesis by using NAD+ intermediates, such as NMN and NR, is expected to ameliorate age-associated physiological decline
WHAT IS NAD+
NAD+ LEVELS DECREASE WITH AGE
As we age, our bodies produce less NAD+ and the communication between the Mitochondria and cell nucleus is impaired. (5,8,10).
NAD+ METABOLISM IN HUMANS
NAD+ can be synthesized in humans from several different molecules (precursors), thru 2 distinct pathways:
De Novo Pathway
- Nicotinic Acid (NA)
- NAM – Nicotinamide
- NR – Nicotinamide Riboside
- NMN – Nicotinamide MonoNucleotide
The NAD+ supply is constantly being consumed and replenished through the Salvage Pathway, with approximately 3g of NAM metabolized to NMN and then to NAD 2-4 times per day (14).
ALL PRECURSORS BOOST NAD+ SIGNIFICANTLY IN LIVER
NAM, NA, NMN, NR, and Tryptophan ALL elevate levels of NAD+ significantly in the liver, which has many benefits for metabolic health.
This chart from the Trammell thesis shows the impact on liver NAD+ for mice given NR, NAM, and NA by oral gavage 0.25, 1, 2, 4, 6, 8 and 12 hours before testing.
Charts showing NMN impact on NAD+ levels in the liver are below.
* Note: These charts are somewhat deceptive. It shows NAM (green bar) elevated NAD+ nearly as much as NR (black bar)
However if they used equal mg of each supplement, which is how people actually purchase and use them, it would show NA about equal with NR and NAM far effective than NR at elevating NAD+ in the liver.
Mice in these experiments didn’t receive equal WEIGHTS of each precursor. Instead researchers chose to use quantity of molecules, which makes NR look “better” by comparison.
In this case, “185 mg kg−1 of NR or the mole equivalent doses of Nam and NA”(16).
Molecular weight for NR is 255 grams, NAM is 122 grams, and NA 123 grams. So this chart used a ratio of 255 grams of NR to 122 and 123 grams of NAM and NA.
- “NMN makes its way through the liver, into muscle, and is metabolized to NAD+ in 30 minutes” (R)
- Is much slower, taking 8 hours to reach peak NAD+ in humans (R)
- Has very similar NAD+ profile to NR, taking 8 hours to reach peak NAD+ in humans (R)
- Has been shown to increase NAD+ level in liver (47%), but was weaker in kidney (2%), heart (20%), blood (43%) or lungs (17%) (R)
- Elevates NAD+ to peak levels in liver in 15 minutes (R)
- raised NAD+ in liver (47%), and impressively raised kidney (88%), heart (62%), blood (43%) and lungs (11%) (R)
- In the liver tryptophan is the preferable substrate for NAD+ production (R)
- Administration of tryptophan, NA, or NAM to rats showed that tryptophan resulted in the highest hepatic NAD+ concentrations(R)
ONLY NMN BYPASSES THE NAMPT BOTTLENECK IN TISSUES THROUGHOUT THE BODY
Restoring NAD+ to youthful levels in ALL CELLS throughout the body is the goal.
However, many tissues cannot utilize NAD+ directly from the blood as NAD+ cannot readily pass through the cellular membrane.
Muscle tissue, for example, depends on cells internal recycling of NAD+ through the salvage pathway which is controlled by Nampt.
To restore depleted NAD+ levels in such cells, a precursor must:
- Be available in the bloodstream
- Once inside a cell, be able to bypass the Nampt bottleneck
NA and Tryptophan
NA and Tryptophan act through the De Novo pathway, which supplies a small percentage of our NAD+, primarily in the liver
NAM is abundant in the blood and easily carried into such cells throughout the body, but depends on Nampt, which is the rate limiting enzyme in the salvage pathway.
When taken orally as a supplement, most NR does not make it through the digestive system intact, but is broken down to NAM (97,98,99).
For more info on how NR is converted to NAM in the body.
NR can bypass the Nampt bottleneck, but is not normally available in the bloodstream
After oral NMN supplementation, levels of NMN in the bloodstream are quickly elevated and remain high longer than NAM, NA, or NR (18,22,97,98,99)
Oral NMN supplements:
- Make their way intact thru the digestive system (22)
- Quickly elevates levels of NMN in the bloodstream for use throughout the body (22)
- Quickly elevates levels of NMN in tissues throughout the body (22)
- Quickly raises levels of NAD+ in blood, liver and tissues through the body (22,23)
- Remain elevated longer than NAM, NA, or NR (18)
Only NMN is readily available in the bloodstream to all tissues, and bypasses the Nampt bottleneck in the Salvage pathway
ORAL NMN IS READILY AVAILABLE THROUGHOUT THE BODY
The chart at right shows levels of a double labeled NAD+ (C13-d-nad+) in liver and soleus muscle at 10 and 30 minutes after oral administration of double labeled NMN.
This clearly shows that NMN makes it way through the liver intact, through the bloodstream, into muscle, and is metabolized to NAD+ in 30 minutes (22) .
This quote below is directly from that study.
Orally administered NMN is quickly absorbed, efﬁciently transported into blood circulation, and immediately converted to NAD+in major metabolic tissues (22).
NMN QUICKLY RAISES NAD+ IN LIVER AND BLOOD
In this 2016 study, mice were given a single dose of NMN in water.
NMN levels in blood showed it is quickly absorbed from the gut into blood circulation within 2–3 min and then cleared from blood circulation into tissues within 15 min
NMN INCREASES NAD+ and SIRT1 DRAMATICALLY IN ORGANS
In this 2017 study, NMN supplementation for 4 days significantly elevated NAD+ and SIRT1, which protected the mice from Kidney damage.
NAD+ and SIRT1 levels were HIGHER in OLD Mice than in YOUNG Mice that did not receive NMN.
LONG TERM SUPPLEMENTATION WITH NMN
In a long-term experiment documented in the 2016 study (22) , mice were given 2 different doses of NMN over 12 months.
Testing revealed that NMN prevents some aspects of physiological decline in mice, noting these changes:
- Decreased body weight and fat
- Increased lean muscle mass
- Increased energy and mobility
- Improved visual acuity
- Improved bone density
- Is well-tolerated with no obvious bad side effects
- Increased oxygen consumption and respiratory capacity
- Improved insulin sensitivity and blood plasma lipid profile
Here are some quotes from the study:
NMN suppressed age-associated body weight gain, enhanced energy metabolism, promoted physical activity, improved insulin sensitivity and plasma lipid profile, and ameliorated eye function and other pathophysiologies
NMN-administered mice switched their main energy source from glucose to fatty acids
These results strongly suggest that NMN has signiﬁcant preventive effects against age-associated impairment in energy metabolism
NMN effectively mitigates age-associated physiological decline in mice
LOWER FAT AND INCREASED LEAN MUSCLE MASS
Researchers found that NMN administration suppressed body weight gain by 4% and 9% in the 100 and 300 mg/kg/day groups.
Analyses of blood chemistry panels and urine did not detect any sign of toxicity from NMN.
Although health span was clearly improved, there was no difference in maximum lifespan observed.
These results suggest that NMN administration can significantly suppress body weight gain without side effects
INCREASED OXYGEN CONSUMPTION AND RESPIRATORY CAPACITY
Oxygen consumption significantly increased in both 100 and 300 mg/kg/day groups during both light and dark periods (Figure 3A).
Energy expenditure also showed significant increases (Figure 3B).
Respiratory quotient significantly decreased in both groups during both light and dark periods (Figure 3C),
This suggests that NMN-administered mice switched their main energy source from glucose to fatty acids.
The mice that had been receiving NMN for 12 months exhibited energy levels, food and water consumption equivalent to the mice in the control group that were 6 months younger.
NMN administration has significant preventive effects against age associated physical impairment
HUMAN STUDIES – LONG TERM SUPPLEMENTATION WITH NMN
The first clinical trial of NMN in humans is currently underway by an international collaborative team between Keio University School of Medicine in Tokyo and Washington University School of Medicine (33).
Participants are 50 healthy women between 55 and 70 years of age with slightly high blood glucose,BMI and triglyceride levels.
Using a dose of 2 capsules of 125mg NMN per day over a period of 8 weeks, researchers are testing for:
- change in insulin sensitivity
- change in beta-cell function
- works to control blood sugar
- blood vessels dilate
- effects of NMN on blood lipids
- effects of NMN on body fat
- markers of cardiovascular and metabolic health
According to the study:
“Data from studies conducted in rodents have shown that NMN supplementation has beneficial effects on cardiovascular and metabolic health, but this has not yet been studied in people”
Testing of metabolic parameter will continue for 2 years after supplementation has ended, so final results will not be published for some time yet, but preliminary results are expected to be announced in early 2018.
FOODS THAT CONTAIN NMN
NMN is found in many food sources such as edamame, broccoli, cucumber,cabbage, avocado, tomato, beef and shrimp.
As such, it is likely free from serious side effects in humans, and has been available for purchase commercially for over 2 years.
In the long term (12 month) 2016 mouse study (22), both 100 and 300mg/kg per day improved oxygen consumption, energy expenditure, and physical activity more.
According to the FDA guidelines, an equivalent would be about 560 mg for a 150lb human.
It should be noted that NMN administration did not generate any obvious toxicity, serious side effects, or increased mortality rate throughout the 12-month-long intervention period, suggesting the long-term safety of NMN.
The current Human study uses a dosage of 2 capsules of 125 mg, which seems to be the most commonly used dosage.
NAD+ levels decrease throughout the body as we age, contributing to disease and aging.
Restoring NAD+ levels can ameliorate many age released health issues.
All the NAD+ precursors are effective at raising NAD+ levels in the liver.
Raising NAD+ in the liver has many benefits, but is not effective in tissues and organs that cannot access NAD+ directly from the bloodstream and so depend on internal cellular NAD+ recycling.
For these tissues, utilizing each cells internal Salvage Pathway is necessary to restore NAD+ levels.
NR is not stable in the body and not normally found in the bloodstream, so is not readily available as NR to many tissues. Once metabolized to NAD+ it cannot enter cells. If metabolized to NAM it cannot bypass the Nampt bottleneck.
NMN is the only precursor that is stable and available to cells through the bloodstream, and can bypass the Nampt bottleneck to quickly restore NAD+ throughout the body.
NMN IS THE WHOLE BODY NAD+ BOOSTER
OTHER RESEARCH WITH NMN
NAD(+) levels were increased significantly both in muscle and liver by NMN
NMN-supplementation can induce similar reversal of the glucose intolerance
NMN intervention is likely to be increased catabolism of fats
NMN-supplementation does mimic exercise
This study showed supplementation with NMN was able to repair the DNA in cells damaged by radiation.
the cells of old mice were indistinguishable from young mice after just one week of treatment.”
Diabetes & Metabolic disease
NMN was immediately utilized and converted to NAD+ within 15 min, resulting in significant increases in NAD+ levels over 60 min
administering NMN, a key NAD+ intermediate, can be an effective intervention to treat the pathophysiology of diet- and age-induced T2D
Surprisingly, just one dose of NMN normalized impaired glucose tolerance
raising NAD+ levels in old mice restores mitochondrial function to that of a young mouse
treatment of old mice with NMN reversed all of these biochemical aspects of aging
restore the mitochondrial homeostasis and key biochemical markers of muscle health in a 22-month-old mouse to levels similar to a 6-month-old mouse
NMN significantly increased the level of NAD+ in the heart
NMN protected the heart from I/R injury
NMN reduces vascular oxidative stress
NMN treatment normalizes aortic stiffness in old mice
NMN represents a novel strategy for combating arterial aging
NMN can reduce myocardial inflammation
NMN thus can cut off the initial inflammatory signal, leading to reduced myocardial inflammation
Remarkably, NMN administered to FXN-KO mice restores cardiac function to near-normal levels.
restoration of cardiac function and energy metabolism upon NMN supplementation
remarkable decrease in whole-body EE and cardiac energy wasting
NMN treats brain injury in ICH by suppressing neuroinflammation/oxidative stress
NMN treatment protects against cICH-induced acute brain injury
NMN treatment reduces brain cell death and oxidative stress
These results further support the neuroprotection of NMN/NAD+
We now demonstrate that mitochondrial respiratory function was restored
NMN could restore cognition in AD model rats.
The beneficial effect of NMN is produced by ameliorating neuron survival, improving energy metabolism and reducing ROS accumulation.
These results suggest that NMN may become a promising therapeutic drug for AD
NMN Treatment Rescues Cognitive impairments
NMN Treatment Improves Inflammatory Responses
Supplementation with NMN restored kidney SIRT1 and NAD+ content in 20-month-old mice and protected both young and old mice from acute kidney injury.