Pictured: Sir Arthur Harden, Nobel Laureate and discoverer of NAD+
I have not yet spent a lot of time on this blog discussing supplements, because I think the focus of good health should be the basics: healthy diet, exercise, good sleep, stress management, and the avoidance of toxic substances such as drugs, tobacco, and excessive alcohol.
This is not to say that supplements don’t have a role, but as a category they suffer from a number of problems. They often are not backed by large and robust studies. The studies that do exist tend to be funded by companies who stand to profit from the supplement, thus introducing the same conflict of interest that “big pharma” is often guilty of with prescription medications. They are not well regulated, so even if “substance X” is truly safe and terrific for your health, you have little guarantee when you purchase “substance X” that you are actually getting “substance X”, unless you make sure to purchase from a reputable place like FullScripts (linked here in case you are interested). And supplements can give people a false sense of security – “I take a multivitamin, and therefore I don’t need to worry about eating healthfully,” or “I take creatine, so I don’t need to actually do a workout” are foolish and potentially dangerous ideas.
With that said, I get asked about this topic a LOT, so I’m going to start periodically reviewing various supplements.
First up in today’s post: NAD+ (and the supplements which help to raise NAD+, namely NMN and NR), which a number of patients have asked me about in the past few months. This is a long and complicated topic and I had to do a lot of research to get up to speed on it, so I am going to break this post into two separate parts, one today and one a week from now. But first let me just give the punchline for those of you who don’t want to read my long ramblings:
I do not think the evidence at this point supports much benefit from taking NAD+ boosting supplements. Moreover, there are some potential safety concerns with supplementing NAD+. I do think there is a possibility that eventually we will find a safe and beneficial way to use these supplements, but for now I would recommend against taking them. I will spend the rest of this post and the next fleshing this out, but if all you want to know is my verdict on this topic, feel free to stop reading here.
And now I will go on to a “FAQ Style” for the remainder of this post, since I think that’s probably the best way to present this information.
What is NAD+? NAD+ stands for Nicotinamide Adenine Dinucleotide. It is an important co-enzyme, first discovered more than a century ago, involved in many hundreds of biological processes all across the human body. A co-enzyme is something that is necessary for an enzyme to work properly; you can think of a co-enzyme as the equivalent of the gas pedal on a car. The car (enzyme) may be great, but it won’t move at all unless someone pushes down on the gas pedal. Similarly, many enzymes in your body will not function unless NAD+ is present, and hence NAD+ plays a vital role in the proper function of virtually every tissue in your body from your heart to your brain to your muscles.
Why Should I Care About NAD+? Starting in the 1990s, a large body of research has established that NAD+ levels decrease as part of the ageing process. This certainly makes sense – the hallmark of aging is that body parts start to not work as well. If NAD+ is crucial to healthy and effective tissue functioning, then it’s not surprising to learn that declining NAD+ levels may be one of the reasons that we age. Therefore there has been great interest over the past 25 years in determining if boosting NAD+ levels can slow the ageing process.
Can I Naturally Boost My NAD+ Levels? The most critical piece of information that you can take from this post is that NAD+ levels get naturally boosted by all sorts of activities that we normally think of as health promoting, including exercise, good sleep, and a healthy diet. It is crucial to grasp this, because it suggests (hardly surprising) that you can slow down aging by adhering to good habits. It also opens up the possibility that boosting NAD levels with artificial supplementation (which I will get to in a second) may not have the same benefits as raising your levels naturally. For example, if you exercise, you will likely boost NAD+ levels, but you will also get lots of other positive benefits, and it may be the combination of these that leads to better health and slower ageing. By contrast, if you take a substance that boosts NAD+ levels, you may get much weaker results – or perhaps none at all.
Are There Ways To Supplement NAD+? Now we come to the heart of today’s topic. In short, there are three known ways to increase NAD+ levels by supplementation:
You Can Get an IV Infusion of NAD+ – this will directly increase NAD+ levels in your bloodstream. However, it requires going to an infusion center, is expensive, and can frequently induce severe nausea, so most people who choose to boost their NAD+ levels opt not to take this route.
You can take a supplement called NMN – NMN, short for Nictotinamide Mononucleotide, is a direct precursor to NAD+ and is available as an over the counter oral supplement, e.g. a pill.
You Can Take a supplement called NR – NR, short for Nicotinamide Riboside, is also available as an over the counter oral supplement. It raises NMN levels in the body, so in effect it’s just another way to boost NMN levels.
Will supplementing with NAD+, NMN, or NR actually increase NAD+ levels in the body? Are there any clear benefits of one supplement over the others? All three of the known methods for supplementing NAD+ mentioned above do seem to boost NAD+ levels in the body, to roughly equivalent levels. Therefore, while we do not yet have good research comparing these three options against each other, if you choose to supplement NAD+, you can reasonably opt for any of the above.
Is It Safe in the short-term to boost NAD+ levels? Yes, there are no apparent serious risks to NAD+ supplementation over a period of weeks to months.
Is there any evidence that boosting NAD+ levels can slow the ageing process? I will delve into this more in my next post, because this is really the crux of the matter. But there are some studies in animals (mice, rats, etc) that show longer life and lower rates of certain diseases when NAD+ levels are boosted.
How popular are NAD+ boosting supplements? These supplements have become extremely popular over the past decade or so, and it’s easy to understand why. Taking everything in this post and putting it together, we know the following:
NAD+ levels are critical to many functions in the human body
NAD+ levels decline with age
We can reliably and safely (at least in the short-term) boost NAD+ levels with one of several widely available supplements (most commonly oral NMN or NR)
Several animal studies show that supplementing NAD+ levels can slow the ageing process.
Given all of this it seems like a slam dunk to think that maybe we should all be taking a daily dose of NMN or NR in order to raise our NAD+ levels, and in 2019 David Sinclair (a Harvard professor who researches longevity) ignited an explosion of interest in doing exactly that when he raved about this possibility on the very popular Joe Rogan podcast.
However, there is more to the story: the benefits in humans are much less clear cut, and there are some reasons to worry about the long-term safety of NAD+ raising supplements. I will delve into all of that in greater detail in my next post.