Impact of NAD+ on Healthy Longevity

NAD⁺ is found in every single living cell, from bacteria to humans.¹

It is required for many reactions that provide energy and for essential cell processes such as repairing DNA.^2-4

The problem is that levels of NAD⁺ decline as we age.⁵

A nutrient called nicotinamide riboside has been shown to boost cellular NAD⁺.

Preclinical studies show that this could support brain,^6-8 heart,⁸ and metabolic health.^8-10

In organisms ranging from yeast to worms to mice, replenishing NAD⁺ with nicotinamide riboside have been found to extend lifespan.^11-14

In one study, elderly mice given nicotinamide riboside experienced a 5% increase in lifespan.¹⁴

For an average American, a 5% lifespan extension would mean four additional years of life.¹⁵

A review published in 2022 describe the systemic effects of NAD⁺ metabolism on cellular aging processes.²

NAD⁺ and Cellular Function

NAD⁺ (nicotinamide adenine dinucleotide) is a coenzyme that is essential to sustaining healthy life.¹⁶

It is critical for the basic metabolism and energy supply of all cells. It is required for the normal function of over 300 proteins, including many vitally important ones.³

For example, sirtuins are a group of proteins that regulate cellular repair and defenses and help maintain cellular health.

Low sirtuin activity is tied to accelerated aging and risk for age-related issues. Preclinical studies have shown that boosting sirtuin function rejuvenates cells, repairs damage to DNA, and much more.^5,16,17

Sirtuins require NAD⁺ to function.¹⁶ For this reason, cells need an ongoing supply of NAD+ at all times to function optimally.

Nicotinamide Riboside Raises NAD⁺ Levels

NAD⁺ production drops significantly with advancing age.^5,18

A study using human skin samples from people across a wide age range found that NAD⁺ levels had declined markedly in people aged 30-50, compared to infants from birth to the age of one year.

In the study subjects over age 50, NAD⁺ levels in skin were reduced by more than 87% compared to the infants'.¹⁹

This decline in NAD⁺ leads to deteriorating cellular health. Sirtuins and other cell protectors that rely on NAD⁺ cannot function properly with insufficient NAD⁺ and cannot offer the defenses that sirtuins provide in youth.¹⁶

There's a way to boost NAD⁺ back to healthier levels. Scientists discovered that a form of vitamin B3 called nicotinamide riboside acts as a NAD⁺ precursor when taken orally.^11,13,14

It is readily taken up by cells, which use it to produce more NAD⁺ and improve body levels of NAD⁺.^20,21

In humans, oral supplementation of nicotinamide riboside 250 mg titrated up to 1,000 mg twice daily was found to raise NAD⁺ levels by 2- to 7-fold.²²

Benefits of Boosting NAD⁺

Ample NAD⁺ levels can contribute to many different areas of health, as suggested by preclinical studies, including:

• Genetic Health. Damage to DNA can cause rapid aging and chronic diseases. By supporting sirtuins and other enzymes, NAD⁺ helps bolster cellular defenses to prevent this damage and even repair existing DNA damage. It also protects the function of telomeres, caps at the ends of chromosomes that are associated with longer life.^3,8,16,17,23
• Energy Metabolism. NAD⁺ plays a central role in breaking down nutrients to supply energy to cells. Without it, cells suffer energy failure and cannot survive.^2-4
• Cellular Protection. Oxidative stress and chronic inflammation have both been tied to virtually every age-related disease. Maintaining adequate NAD⁺ combats both, inhibiting inflammation while aiding cellular antioxidant defenses.^17,24
• Stem Cell Health. Healthy stem cells help maintain youthful tissue function, replacing old, damaged cells with healthy new ones. In animal model studies both NAD⁺ and sirtuins have been found to improve stem cell health.^14,25-27

Nicotinamide Riboside Promotes Longevity

Scientists have consistently found in preclinical studies that NAD⁺-boosting nicotinamide riboside is capable of improving overall health, including the brain,^28,29 heart,^30-32 and blood vessels.³³

For example, in rodent studies, nicotinamide riboside:^28,31

• Reverses cognitive deficits and improves memory in models of Alzheimer's disease,²⁸
• Helps prevent the development of heart failure,³¹ and
• Improves metabolism and helps prevent weight gain.²⁸

A range of preclinical models have demonstrated that increasing nicotinamide riboside NAD⁺ levels can extend lifespan.^11-14

Yeast grown with nicotinamide riboside have an extended lifespan.¹¹ In worms, lifespan is extended at least 10%.¹³

Giving nicotinamide riboside to mice that were the human equivalent of 70 years old¹⁴ extended their lives by about 5%.

A 5% extended lifespan in a person might mean gaining nearly four additional years of life based on today’s average U.S. human life expectancy of roughly 76 years.¹⁵

Clinical Trials

Impressed by all the animal studies showing benefits for boosting NAD⁺, scientists began conducting clinical studies with nicotinamide riboside to see if the benefits would translate to humans.  Here is a sampling of human trials.

• A double blinded phase 1 clinical trial of newly diagnosed Parkinson's disease patients received 1,000 mg or placebo for 30 days. Participants receiving nicotinamide riboside showed an increase in brain NAD⁺ levels and mild improvement of clinical symptoms.³⁴
• In a double-blind, crossover trial, aged men received 1,000 mg nicotinamide riboside per day for 21 days. After 21 days elevated levels of NAD⁺ in muscles of participants in intervention group were seen. Nicotinamide riboside also reduced levels of circulating inflammatory cytokines.³⁵
• In a clinical trial of 30 participants with clinically stable heart failure and reduced ejection fraction, 1000 mg twice daily dose of nicotinamide riboside was well tolerated and resulted in boosting blood levels of NAD⁺ to approximately double the level at baseline and reduced white blood cell expression of markers of systemic inflammation.³⁶
• In a double blind, crossover study 12 young and 12 aged individuals were randomized to receive nicotinamide riboside or placebo. Two hours before and after the supplementation, blood and urine samples were collected. At that time muscle fatigue and strength were assessed. Nicotinamide riboside supplementation showed increased NAD⁺ levels.  Interestingly, supplementation improved physical performance only in elderly subjects.³⁷ The conclusion from this finding indicates that declining NAD⁺ levels due to age can be replenished with nicotinamide riboside supplementation, resulting in improved exercise performance.

Summary

NAD⁺ is a crucial compound in every living cell.

It is involved in the basic energy supply all cells need to thrive. It is also required for cellular regulators like sirtuins to help protect against rapid aging.

NAD⁺ levels drop dramatically with age, contributing to accelerated aging.

Nicotinamide riboside is a NAD⁺ precursor. Taken orally, it quickly boosts cellular NAD⁺ levels.

In preclinical studies, nicotinamide riboside is tied to improved organ function and longer life.

If you have any questions on the scientific content of this article, please call a Life Extension Health Advisor at 1-866-864-3027.

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