Whats the TRUTH about Nicotinamide Riboside (NIAGEN)

NAD+ is the key for Healthy Aging

As we age, our levels of the Co-enzyme Nicotinamide Adenine Dinucleotide NAD+ drop significantly in multiple organs in mice and humans (5, 8, 10).

NAD+ is a key Co-enzyme used by our mitochondria for energy production in all our cells. Higher NAD+ levels are needed for our cells to function at their best.

NAD+ decrease is described as a trigger in age-associated decline(23), and perhaps even the key factor in why we age (5).

Nicotinamide Riboside (NR) and Nicotinamide Mononucleotide (NMN) are precursors used by the body to create more NAD+. Oral supplementation with NR and NMN can increase NAD+ levels.

Elevating NAD+ with Supplements

In 2013, research published by Dr David Sinclair demonstrated that short term supplementation with Nicotinamide MonoNucleotide (NMN) replenished NAD+ and reversed many aspects of aging, making the cells of old mice resemble those of much younger mice, and greatly improving their health (8).

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.


NAD+ 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).

  • The salvage pathway sustains 85% or more of our NAD+ (14)
  • Nampt is the rate-limiting step in the salvage process (97).
  • As we age, Nampt enzyme activity is lower, resulting in less NAM recycling, less NAD+, more disease and aging (97, 101).


NMN is the immediate precursor to NAD+, and is after Nampt in the salvage process, so NMN bypasses the Nampt bottleck

In 2004 Dr Charles Brenner published a paper showing that the enzyme Nrk1 can catalyze Nicotinamide Riboside directly to Nicotinamide Mononucleotide (100), which means that any NR that makes it’s way into the bloodstream can theoretically bypass the NAMPT bottleneck.

Although NR is unstable by itself, Dartmouth University has patented production methods that combine it with Chloride which makes it stable outside the body

Chromadex has licensed this technology and has been selling Nicotinamide Riboside commercially since 2014 under the brand name “Niagen”.

Tru Niagen™ is the brand name used by Dr Brenner’s company ProHealthSpan to market their Niagen product.

Digested to NAM

When taken orally as a supplement, most NR does not make it through the digestive system intact, but is broken down to NAM. This quote below is from the most recent review of Therapeutic Potential of NMN and NR.

Substantial fraction of orally administered NR is likely converted into nicotinamide by first-pass metabolism in the liver or by hydrolysis in the blood circulation before its uptake into other tissues (102)

For more info on how NR is converted to NAM in the body.

Not found in bloodstream

In both mice and humans, studies repeatedly failed to find any NR in the bloodstream at any time, even after very high dosages of NR (97, 98, 99).

The following quote from this Dr Brenner study also did not find NR in bloodstream after oral supplements, but was found in trace amounts after Injection

NR varied and displayed no response to NR administration… but was detected after IP of double labeled NR

A small fraction makes it intact to muscle
and other tissues outside Liver

The charts at left are from this 2016 study which used mice that have had the gene for Nampt ‘knocked out’ in quadricep muscle, so are unable to process NAM. As a result, the NAD+ levels drop to 15% of normal.

These mice were fed double labelled NR to track the movement of the NR through the body.

Any NR that makes it through digestion intact would be incorporated as double labelled NAD (M+2). NR that has been metabolized to NAM loses 1 heavy tracking molecule and would be found as M+1.

Chart D shows both single and double labelled NAD+ (green and red) are abundant in roughly equal amounts in the liver.

Chart C shows quite a lot of single labelled NAD+ in the muscle which is from NR that has been metabolized to NAM and then NMN.

We know this NAD+ was metabolized as NAM and then NMN because these mice lacked Nampt in muscle, so can not process NAM.

At the same time, there is only a tiny fraction of double labelled NAD+ in the muscle.

This demonstrates that NMN, but not NR was readily available for use in the Salvage Pathway inside the muscle.

Very Fast to Liver and muscle tissue

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)

The chart at left 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).

Orally administered NMN is quickly absorbed, efficiently transported into blood circulation, and immediately converted to NAD+in major metabolic tissues (22).

Elevates NAD+ quickly throughout the body

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

Increases NAD+ and Sirt1 Dramatically in organs

The charts at left from 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.

NMN Bioavailability Summary

  • 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)

NAD+ levels decrease throughout the body as we age, contributing to disease and aging. Restoring NAD+ levels can ameliorate many age released health issues.

A large percentage of NR is first digested to NAM, so it cannot bypass the Nampt bottleneck in many tissues. NR is effective at elevating NAD+ in the Liver, but is not stable in the body and not normally found in the bloodstream, which limits it’s effectiveness.

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.


  1. Detection and pharmacological modulation of nicotinamide mononucleotide (NMN) in vitro and in vivo (Formentini, 2009)
  2. AMPK regulates energy expenditure by modulating NAD+ metabolism and SIRT1 activity (Cato, 2009)
  3. A possibility of nutriceuticals as an anti-aging intervention: activation of sirtuins by promoting mammalian NAD biosynthesis (Imai, 2010)
  4. NAD blocks high glucose induced mesangial hypertrophy via activation of the sirtuins-AMPK-mTOR pathway (Zhuo, 2011)
  5. Nicotinamide Mononucleotide, a Key NAD+ Intermediate, Treats the Pathophysiology of Diet- and Age-Induced Diabetes in Mice (Yoshino, 2011)
  6. The NAD (+) precursor nicotinamide riboside enhances oxidative metabolism and protects against high-fat diet-induced obesity(Canto, 2012 )
  7. NAD⁺ repletion improves mitochondrial and stem cell function and enhances life span in mice. (Zhang, 2016)
  8. Declining NAD+ Induces a Pseudohypoxic State Disrupting Nuclear-Mitochondrial Communication during Aging (Gomes, Sinclair,2013)
  9. Nicotinamide mononucleotide, an intermediate of NAD+ synthesis, protects the heart from ischemia and repercussion (Yamamoto, 2014)
  10. NAD+ and sirtuins in aging and disease (Imai, 2014)
  11. Effective treatment of mitochondrial myopathy by nicotinamide riboside, a vitamin B3 (Khan, 2014)
  12. Effect of nicotinamide mononucleotide on brain mitochondrial respiratory deficits in an Alzheimer’s disease-relevant murine model (Long, 2015)
  13. NAD+ metabolism and the control of energy homeostasis – a balancing act between mitochondria and the nucleus (Canto, 2015)
  14. NAD+ metabolism: Bioenergetics, signaling and manipulation for therapy (Yang, 2016)
  15. NAD+ replenishment improves lifespan and healthspan in ataxia telangiectasia models via mitophagy and DNA repair( Fang, 2016 )
  16. Nicotinamide riboside is uniquely and orally bioavailable in mice and humans(Trammell, 2016a )
  17. Nicotinamide riboside opposes type 2 diabetes and neuropathy in mice(Trammell, 2016b )
  18. β-Nicotinamide Mononucleotide, an Anti-Aging Candidate Compound, Is Retained in the Body for Longer than Nicotinamide in Rats (Kawamura, 2016)
  19. The first human clinical study for NMN has started in Japan (Tsubota, 2016)
  20. Nicotinamide mononucleotide protects against β-amyloid oligomer-induced cognitive impairment and neuronal death (Wang, 2016)
  21. Head to Head Comparison of Short-Term Treatment with the NAD(+) Precursor Nicotinamide Mononucleotide (NMN) and 6 Weeks of Exercise in Obese Female Mice (Uddin, 2016)
  22. Long-Term Administration of Nicotinamide Mononucleotide Mitigates Age-Associated Physiological Decline in Mice (Mills, 2016)
  23. Nicotinamide mononucleotide supplementation reverses vascular dysfunction and oxidative stress with aging in mice (de Picciotto, 2016)
  24. Nicotinamide mononucleotide inhibits JNK activation to reverse Alzheimer disease (Yao, 2017)
  25. Nicotinamide mononucleotide requires SIRT3 to improve cardiac function and bioenergetics in a Friedreich’s ataxia cardiomyopathy model (Martin, 2017)
  26. Nicotinamide Mononucleotide, an NAD+ Precursor, Rescues Age-Associated Susceptibility to AKI in a Sirtuin 1-Dependent Manner (Guan, 2017)
  27. Nicotinamide mononucleotide attenuates brain injury after intracerebral hemorrhage by activating Nrf2/HO-1 signaling pathway (Wei, 2017)
  28. Short-term administration of Nicotinamide Mononucleotide preserves cardiac mitochondrial homeostasis and prevents heart failure (Zhang, 2017)
  29. Modulating NAD+ metabolism, from bench to bedside (Auwerx, 2017)
  30. Aspects of Tryptophan and Nicotinamide Adenine Dinucleotide in Immunity: A New Twist in an Old Tale. (Rodriguez, 2017)
  31. Vitamin B3 modulates mitochondrial vulnerability and prevents glaucoma in aged mice (Williams, 2017)
  32. NAMPT-mediated NAD biosynthesis as the internal timing mechanism: In NAD+ World, time is running in its own way (Poljsak, 2017)
  33. Effect of “Nicotinamide Mononucleotide” (NMN) on Cardiometabolic Function (NMN)
  34. The dynamic regulation of NAD metabolism in mitochondria (Stein, 2012)
  35. Novel NAD+ metabolomic technologies and their applications to Nicotinamide Riboside interventions (Trammel, 2016)
  36. Long-term moderate calorie restriction inhibits inflammation without impairing cell-mediated immunity: a randomized controlled trial in non-obese humans (Meydayni, 2016)
  37. A high-fat, ketogenic diet induces a unique metabolic state in mice. (Kennedy, 2007)
  38. Ketone body metabolism and cardiovascular disease.(Cotter, 2013)
  39. Ketone bodies as signaling metabolites(Newman, 2014)
  40. The ketone metabolite β-hydroxybutyrate blocks NLRP3 inflammasome–mediated inflammatory disease(Youm, 2015)
  41. The effect of the Spanish Ketogenic Mediterranean Diet on nonalcoholic fatty liver disease: a pilot study.(Guisado, 2011)
  42. β-Hydroxybutyrate: A Signaling Metabolite in starvation response(Morales, 2016)
  43. Physiological roles of ketone bodies as substrates and signals in mammalian tissues(Robinson, 1980)
  44. Ketone bodies mimic the life span extending properties of caloric restriction (Veech, 2017)
  45. Novel ketone diet enhances physical and cognitive performance(Murray, 2016)
  46. Mitochondrial biogenesis and increased uncoupling protein 1 in brown adipose tissue of mice fed a ketone ester diet.
  47. Nutritional Ketosis Alters Fuel Preference and Thereby Endurance Performance in Athletes(Cox, 2013)
  48. Neuroendocrine Factors in the Regulation of Inflammation: Excessive Adiposity and Calorie Restriction (Fontana, 2009)
  49. Beta-adrenergic receptors are critical for weight loss but not for other metabolic adaptations to the consumption of a ketogenic diet in male mice(August, 2017)
  50. A randomized trial of a low-carbohydrate diet for obesity(Foster, 2003)
  51. β-Hydroxybutyrate suppresses inflammasome formation by ameliorating endoplasmic reticulum stress via AMPK activation(Bae, 2016)
  52. The neuroprotective properties of calorie restriction, the ketogenic diet, and ketone bodies. (Maalouf, 2009)
  53. AMPK activation protects cells from oxidative stress‐induced senescence via autophagic flux restoration and intracellular NAD + elevation (Han, 2016)
  54. Regulation of AMP-activated protein kinase by natural and synthetic activators (Hardie, 2015)
  55. Effects of Exhaustive Aerobic Exercise on Tryptophan-Kynurenine Metabolism in Trained Athletes (Strasser, 2016)
  56. PARP-1 inhibition increases mitochondrial metabolism through SIRT1 activation(Bai, 2011)
  57. Carbohydrate restriction regulates the adaptive response to fasting (Klein, 1992)
  58. Interventions to Slow Aging in Humans: Are We Ready? (longo, 2015)
  59. Extending healthy life span–from yeast to humans (longo, 2010)
  60. Dietary restriction with and without caloric restriction for healthy aging (Lee, 2016)
  61. A Periodic Diet that Mimics Fasting Promotes Multi-System Regeneration, Enhanced Cognitive Performance, and Healthspan (Longo, 2015)
  62. Diet mimicking fasting promotes regeneration and reduces autoimmunity and multiple sclerosis symptoms (Longo, 2016
  63. Resistance Exercise Training Alters Mitochondrial Function in Human Skeletal Muscle (Porter, 2015)
  64. Ketogenic Diet Reduces Midlife Mortality and Improves Memory in Aging Mice (Newman, 2017)
  65. The NAD(+)/sirtuin pathway modulates longevity through activation of mitochondrial UPR and FOXO signaling.  (Mouchiroud, 2013)
  66. NAMPT- mediated NAD(+) biosynthesis is essential for vision in mice  (Lin, 2016)
  67. NAD+ replenishment improves lifespan and healthspan in ataxia telangiectasia models via mitophagy and DNA repair( Fang, 2016 )
  68. Inhibiting poly ADP-ribosylation increases fatty acid oxidation and protects against fatty liver disease (Gariani, 2017 )
  69. Interdependence of AMPK and SIRT1 for metabolic adaptation to fasting and exercise in skeletal muscle(Canto, 2010)
  70. The NAD (+) precursor nicotinamide riboside enhances oxidative metabolism and protects against high-fat diet-induced obesity(Canto, 2012 )
  71. Nicotinamide riboside is uniquely and orally bioavailable in mice and humans(Trammell, 2016a )
  72. Nicotinamide riboside opposes type 2 diabetes and neuropathy in mice(Trammell, 2016b )
  73. Dietary leucine stimulates SIRT1 signaling through activation of AMPK (Hongliang, 2012)
  74. Effective treatment of mitochondrial myopathy by nicotinamide riboside, a vitamin B3 (Khan, 2014)
  75. NAD blocks high glucose induced mesangial hypertrophy via activation of the sirtuins-AMPK-mTOR pathway (Zhuo, 2011)
  76. The effect of different exercise regimens on mitochondrial biogenesis and performance (Philander, 2014)
  77. Dietary proanthocyanidins boost hepatic NAD+ metabolism and SIRT1 expression and activity in a dose-dependent manner in healthy rats (Aragon’s, 2016)
  78. NAD+ Deficits in Age-Related Diseases and Cancer (Garrido, 2017)
  79. Anti-diabetic and anti-lipidemic effects of chlorogenic acid are mediated by ampk activation (Ong, 2013)
  80. Chlorogenic Acid Improves Late Diabetes through Adiponectin Receptor Signaling Pathways in db/db Mice (Chang, 2015)
  81. Adenosine Monophosphate (AMP)-Activated Protein Kinase: A New Target for Nutraceutical Compounds (Marin-Aguilar, 2017)
  82. The Effects of Ramadan Fasting on Body Composition, Blood Pressure, Glucose Metabolism, and Markers of Inflammation in NAFLD Patients: An Observational Trial (Mazidi, 2014)
  83. Comparative effects of carbohydrate versus fat restriction on metabolic profiles, biomarkers of inflammation and oxidative stress in overweight patients with Type 2 diabetic and coronary heart disease: A randomized clinical trial. (Raygan, 2016)
  84. Normal fasting plasma glucose and risk of type 2 diabetes diagnosis (Nichols, 2008)
  85. Are We All Pre-Diabetic? (Stokel,2016)
  86. Hepatic NAD+ deficiency as a therapeutic target for non-alcoholic fatty liver disease in aging (Zhou, 2016)
  87. Effect of exercise intensity on post-exercise oxygen consumption and heart rate recovery (Mann,2014)
  88. A 45-minute vigorous exercise bout increases metabolic rate for 14 hours (Knab,2011)
  89. Effects of high-intensity resistance training on untrained older men. II. Muscle fiber characteristics and nuclei-cytoplasmic relationships (Gerontol, 2000)
  90. Ketogenic Diet Reduces Midlife Mortality and Improves Memory in Aging Mice (Newman, 2017)
  91. A Ketogenic Diet Extends Longevity and Healthspan in Adult Mice (Roberts, 2017)
  92. NK cells link obesity-induced adipose stress to inflammation (Wensveen, 2015)
  93. The “Big Bang” in obese fat: Events initiating obesity-induced adipose tissue inflammation (Wensveen, 2015)
  94. The impact of the Standard American Diet in rats: Effects on behavior, physiology and recovery from inflammatory injury(Totsch, 2017)
  95. Bioenergetic state regulates innate inflammatory responses through the transcriptional co-repressor CtBP (Shen, 2017)
  96. The Ketogenic Diet as a Treatment Paradigm for Diverse Neurological Disorders (Stafstrom, 2012)
  97. Loss of NAD Homeostasis Leads to Progressive and Reversible Degeneration of Skeletal Muscle (Fredrick 2016)
  98. Digestion and absorption of NAD by the small intestine of the rat (Henderson, 1983)
  99. Effects of a wide range of dietary nicotinamide riboside (NR) concentrations on metabolic flexibility and white adipose tissue (WAT) of mice fed a mildly obesogenic diet(Shi, 2017)
  100. Discoveries of nicotinamide riboside as a nutrient and conserved NRK genes establish a Preiss-Handler independent route to NAD+ in fungi and humans (Brenner, 2004)
  101. Nampt Expression Decreases Age-Related Senescence in Rat Bone Marrow Mesenchymal Stem Cells by Targeting Sirt1 (Ma, 2017)
  102. NAD+ Intermediates: The Biology and Therapeutic Potential of NMN and NR (Yoshino, 2017)