In humanity’s eternal race for optimal longevity, one molecule continues to draw great interest – NAD (nicotinamide adenine dinucleotide). This is a critical coenzyme involved in vital processes such as energy production, DNA repair, mitochondrial function, and the regulation of many cellular processes. With age, NAD levels in the body gradually decline, which may contribute to aging processes and deterioration in cellular function.
The logic behind taking supplements that promote NAD production – such as NR (nicotinamide riboside) and NMN (nicotinamide mononucleotide) – is based on the assumption that increasing NAD levels could slow aging processes and even improve health markers. Since NAD itself does not easily penetrate cells, the preferred approach today is to take NR and NMN, which the body knows how to convert into NAD through metabolic processes.
Several preliminary studies have shown that taking NMN in doses such as 600–900 mg per day does indeed raise NAD levels in the blood. However, the clinical effect remains unclear and raises questions. Small trials point to marginal improvements – for example, modest improvement in walking ability or in metabolic markers – but these were conducted in relatively healthy populations, with measures that are difficult to interpret as having true clinical significance.
Some doctors express cautious interest in these supplements, but emphasize that as of today there are not enough large, randomized, high-quality human studies showing a real impact on health measures or on life expectancy. The scientific community approaches the subject with great caution, stressing the need for further and longer-term studies.
The worrying trend: Intravenous injections
In recent years, intravenous NAD injections have also become popular, especially in private clinics offering “anti-aging treatments” or “cellular rejuvenation.” It is important to clarify: No one really knows today what the difference is in physiological effect between oral intake and injection, since there are almost no studies directly comparing the two.
What is known – with injection, especially in high doses or with rapid infusion, there are often significant side effects such as nausea, headaches, chest pressure, anxiety, a “burning” sensation in the body, and sometimes even a drop in blood pressure. These are effects that must be taken seriously, especially when there is no clear proof of medical benefit.
Therefore, the current recommendation is to exercise great caution. NMN and NR supplements are considered relatively safe, but they are very expensive, and there is no clear evidence that they contribute to overall health or extend life. As long as information is limited and no significant clinical effect has been proven, it is better to focus on what is already known to be beneficial: Proper nutrition, regular physical activity, adequate sleep, emotional balance, and personalized medical follow-up.
What is the gain – and also the cost?
In the bottom line – it must be remembered that even when there is convincing physiological logic, it does not necessarily mean this will happen in practice. Without human-based studies, it is difficult to really know the true effect. Therefore, before rushing to adopt every “innovative” supplement or treatment, it is important to ask not only “what is the possible gain?” but also “what is the possible cost?” – especially in the spirit of medicine’s basic principle: First of all – do no harm.
Science continues to progress, and our understanding of the NAD molecule and its role in the body is deepening. However, at present, the gap between scientific theory and real clinical evidence is still too great to recommend the widespread use of these supplements or injections.
For further reading and deeper learning: If you would like to learn about this topic and other similar topics in depth, you are welcome to listen to the podcast of Dr. Peter Attia and Dr. Huberman here.
Dr. Roy Zucker is a specialist in internal medicine, Medical Director at BREEOOT.