Cost-Effective Option to Boost NAD+

There’s a good reason why NAD+ is found in every living cell in our bodies.¹

NAD+ is required for hundreds of critical cellular processes, including energy production, DNA repair, and immune responses.^2-4

It plays critical roles in processes related to aging at the cellular level.^2,5

But NAD+ levels decrease as we age, which can contribute to age-related functional decline.^2,6,7 NAD+ precursors are compounds that have been shown to boost NAD+ when taken orally and have the potential to support healthier aging.⁸

Life Extension® readers are familiar with the NAD+ precursor nicotinamide riboside or NR. It was introduced to readers of this publication in 2014. A lower-cost and effective

NAD+ precursor, called NMN (nicotinamide mononucleotide), has recently entered the commercial marketplace.

In controlled human trials, oral NMN supplementation significantly increased blood NAD+ levels compared to placebo. NMN is a lower-cost way to boost NAD+.^9,10

NMN may support healthy aging at the cellular level via increased NAD+ production.

The Importance of NAD+

The coenzyme NAD+ (nicotinamide adenine dinucleotide) is essential for normal cellular function.^4,11

Without ample NAD+, cells cannot properly convert food into usable energy or effectively mitigate DNA damage.^4,11 NAD+ is required for the normal function of over 300 proteins, including:²

• Sirtuins, which maintain mitochondrial health, suppress chronic inflammation, and help regulate cell metabolism,^12,13
• PARPs (poly-ADP ribose polymerases), which handle DNA repair, autophagy (cell cleanup), and gene regulation,^2,13 and
• CD38 (cyclic ADP-hydrolysase), which supports immune responses and calcium signaling.^2,13

NAD+ is critical for all cells. Preclinical data shows that it is a key mediator in energy metabolism, DNA repair, cellular antioxidant defenses, inflammation regulation, and more.^2,5,13-15

Why NAD+ Declines as You Age

NAD+ levels progressively decline across multiple human tissues and have been associated with age-related chronic disorders and metabolic dysfunction.^6,16

With age, cellular damage accumulates due to inflammation, oxidative stress, and DNA damage.

Sirtuins, PARPs, and CD38 help mitigate this damage.^13,16,17 But to function properly, these critical proteins “consume” NAD+ thereby depleting levels.¹⁸ This decline is continuous and progressive. One human observational study showed that by age 50, NAD+ levels can drop by about 50%.¹⁹

Decreased NAD+ levels are associated with reduced mitochondrial function and increased risk of premature aging and chronic age-related conditions.^16,17,19,20

Restoring NAD+ Levels

Orally consuming NAD+ is not an effective way to replenish levels. In addition to being poorly absorbed, it cannot readily pass through the cell membrane intact.^21,22

To get around this problem, scientists studied NAD+ precursors, compounds that can be taken orally to boost NAD+. Two precursors have been shown in clinical studies to raise blood NAD+ levels significantly, efficiently, and safely:

NR (nicotinamide riboside),^23,24 and

NMN (nicotinamide mononucleotide).^9,10

A Lower-Cost Option

In 2014, Life Extension researchers were among the first to recognize the importance of boosting NAD+ throughout the body for cellular health.

Nicotinamide riboside was recommended 12 years ago as a method to boost NAD+ levels.

Another option to boost NAD+ is to supplement using NMN.

In 2022, however, the FDA formally classified NMN as a drug.²⁵

In late 2025, that classification was removed, allowing NMN to re-enter the consumer marketplace as an officially recognized dietary supplement.^26,27

Both NR and NMN boost NAD+ levels in a similar fashion and at equivalent levels. However, NMN can be produced at a lower cost.

This allows aging individuals to boost their NAD+ levels in a more cost-effective way.

NMN and NR have both been clinically shown to boost NAD+ levels. They have overlapping as well as unique pathways for cellular entry.¹⁷

NR has two main pathways:

• NR can be directly transported into the cell where it then needs to be converted into NMN to produce NAD+.
• NR can be metabolized by the gut before entering the cell and producing NAD+.

NMN has three main pathways:

• NMN is converted into NR to enter the cell where it then gets converted back into NMN to produce NAD+.
• NMN can also be metabolized by the gut before entering the cell and producing NAD+.
• NMN appears to have a unique cell transporter that allows for direct entry into the cell where it produces NAD+. (However, this is evolving science and has so far only been described in animal studies.)²⁸

Importantly, regardless of the pathways that NR or NMN use, studies have shown increases in NAD+ production.

Benefits of NMN

Preclinical studies suggest that NMN may support aspects of healthy aging by boosting NAD+.

In one study, giving mice NMN for 12 months:²⁹

• Increased energy metabolism,
• Boosted physical activity levels,
• Decreased age-associated weight gain,
• Improved insulin sensitivity and blood lipid levels, and
• Reduced age-related gene-expression changes.

A second study administered NMN throughout the lifespan of a premature aging mouse model, starting at an early age. These mice exhibited:³⁰

• Increased lifespan and improved median life expectancy,
• Reduced frailty, and
• Better overall health.

Validated in Clinical Studies

In a clinical study, healthy older men (mean age 71) were given 250 mg of NMN or a placebo.

After 12 weeks, NMN significantly increased NAD+ levels compared to placebo.⁹

In another clinical study, healthy older men and women (mean age 69) were given 250 mg of NMN or a placebo.

Again, after 12 weeks, NMN significantly increased NAD+ levels compared to the placebo group.¹⁰

In both trials, NMN also increased levels of other NAD+ precursors and intermediates. This provides additional evidence that NMN raises NAD+ levels.^9,10

These higher NAD+ levels may help support healthy aging.

Summary

NAD+ (nicotinamide adenine dinucleotide) is a compound found in every living cell in the body. It’s required for essential cellular processes like energy production, DNA repair, and immune function. 

Levels of NAD+ decline with age, reducing mitochondrial function and accelerating aging. The precursor NMN (nicotinamide mononucleotide), taken orally, can boost NAD+ levels.

Clinical studies show that NMN safely increases NAD+ levels in older adults, which may support healthy aging at the cellular level.

Consumers now have access to NMN or NR. The major difference from our view is that NMN costs far less than NR. n

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

References

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