NAD+: A Miracle Anti-Aging Drug or an Unfulfilled Promise?

Aging is a natural and inevitable process, but it is accompanied by a gradual decline in physical and cognitive function. In recent years, there has been significant progress in research and development of innovative therapeutic approaches aimed at slowing the aging process. One of the molecules generating the greatest excitement in this field is NAD+, or Nicotinamide Adenine Dinucleotide. But there is a gap between promise and reality, and it is worth knowing both.

Biological Roles of NAD+:

NAD+ plays many vital roles in cellular function and body health, including:

• Metabolism: NAD+ is essential for extracting energy from food. It is a central redox molecule in cellular respiration, where food molecules are broken down and converted into usable energy (ATP). A decline in NAD+ levels impairs cellular energy production and can harm the function of various body systems.
• DNA Repair: NAD+ is a necessary substrate for PARP enzymes and sirtuins, which are involved in repairing DNA damage. This damage accumulates with age and contributes to aging, and proper DNA repair is vital for maintaining cell health. A decline in NAD+ levels can impair DNA repair capacity.
• Immune System Regulation: NAD+ is involved in regulating the activity of immune system cells. Laboratory and animal studies link low NAD+ levels to less efficient immune function, but how applicable this is to healthy humans is still unclear.
• Protection Against Oxidative Stress: NAD+ and its reduced form NADH participate in the cell's defense systems against damage from oxidative stress. Oxidative stress is a natural process in the body, but an excess can harm cells and contribute to disease.

The Connection Between NAD+ and Aging:

Many studies indicate that NAD+ levels in various tissues, such as muscle and brain, tend to decline with age. However, it is important to be precise: whether NAD+ levels in the blood decline in healthy people is not clear-cut, and studies yield conflicting results. A decline in tissue NAD+ levels has been linked in studies to a variety of age-related diseases, such as:

• Cardiovascular Disease: A decline in NAD+ levels has been linked to impaired heart and blood vessel function and a potential increase in the risk of cardiovascular disease.
• Diabetes: NAD+ is involved in regulating sugar metabolism. A decline in NAD+ levels has been linked to an increased risk of diabetes.
• Neurodegenerative Diseases: A decline in NAD+ levels has been linked to neurodegenerative diseases, such as Alzheimer's disease and Parkinson's disease.
• Cancer: The connection between NAD+ and cancer is bidirectional and complex. On one hand, NAD+ supports DNA repair and may thus protect against cancer development. On the other hand, cancer cells need NAD+ to produce energy and thrive, so there is a theoretical concern that raising NAD+ levels could actually fuel existing cancer cells. This is one reason for caution, especially in people with active cancer.

Ways to Increase NAD+ Levels:

• Diet: Consuming foods rich in NAD+ precursors, such as meat, fish, green vegetables, and fruits.
• Supplements: There are dietary supplements containing NAD+ precursors, such as NMN and NR.
• Physical Activity: Physical activity may support NAD+ production in the body.
• Medical Treatments: There are experimental treatments aimed at increasing NAD+ levels in the body.

Scientific Research:

Studies conducted on animals have shown that increasing NAD+ levels may slow specific age-related functional declines. These studies reported improvements in physical and cognitive function in rodents, and in some cases, also extended lifespan and reduced signs of age-related diseases. This is precisely where the main gap lies: in humans, the picture is much more modest. Clinical trials consistently show that NMN and NR supplements indeed increase NAD+ levels in the blood, sometimes even doubling them. But when examining actual functional improvement, the results so far have been modest or absent: effects on cardiovascular function, cognitive function, and muscle strength and performance were small, inconsistent, and sometimes not significantly different from placebo. In other words, raising the number on a blood test is one thing, translating it into a noticeable health benefit is quite another.

Concerns and Challenges:

• Dosage: It is still unclear what the optimal dosage of NAD+ precursors is for maximum effect.
  Further studies are needed to determine the safest and most effective dosage for humans.
• Safety: More research is needed to ensure the safety of long-term use.
  Long-term studies can assess the potential risks and side effects of these treatments.
• Accessibility: Dietary supplements containing NAD+ precursors are relatively expensive.
  Developing more effective and accessible approaches will be a significant challenge.
• Drug Interactions: The effects of NAD+ precursors on other medications need to be examined.
  Taking them could affect the efficacy and safety of certain drugs.

Summary:

NAD+ is a molecule with a central biological role and interesting potential in the field of aging. Basic research and animal studies are promising, but the evidence in humans is still far from establishing NAD+ as a miracle drug: the supplements reliably increase NAD+ levels in the blood, but have yet to demonstrate clear functional benefit. Therefore, the fairest headline is exactly the one at the top of this article: not a certain miracle drug, but a promise still awaiting fulfillment. Large, long-term, well-controlled studies are needed to understand what NAD+ can really do for human health.

Recommendations:

• Consult a Doctor: Before taking dietary supplements containing NAD+ precursors, consult a doctor.
  A doctor can assess the need for these supplements, especially in people with underlying conditions, and determine the appropriate dosage.
• Follow New Research: The field of NAD+ research is developing rapidly, and it is recommended to follow new studies to get the most up-to-date information.
• Adopt a Healthy Lifestyle: A healthy lifestyle, including proper nutrition, physical activity, and adequate sleep, remains the most established foundation for health.
  A healthy lifestyle can support normal aging processes and improve quality of life over time.

Sources:

References:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10240123/