8 Key Differences Between NMN & NR
Not all NAD precursors are alike.
If you’ve been keeping up with aging and science news, you’ve probably already heard of a critical molecule known as nicotinamide adenine dinucleotide (NAD). You may even already know that NAD is critical to human survival and that it decreases as we get older and undergo metabolic stresses. There are a few different ways of increasing NAD, and although the science here is important, it can easily turn into an eye-glazing-over experience for most people who don’t study cells for a living.
Here's a quick breakdown of the key differences between nicotinamide mononucleotide (NMN) and nicotinamide riboside (NR):
1. NR is a vitamin. NMN is not.
NR is a proven form of vitamin B3 which is required to sustain healthy living. It’s shown in multiple human studies to effectively increase NAD levels. NMN is not considered a form of vitamin B3 for two main reasons: it contains a phosphate which affects NMN’s ability to enter cells, and there are currently no published clinical trials to prove it increases NAD in humans.
2. NR has at least 4 published human clinical studies. NMN has 0.
NR has at least four published clinical trials and all of them confirm NR is a safe and effective way of increasing NAD in people. NMN’s only published trials are in mice and rats.*
3. NR’s trials confirm it’s safe for humans. NMN’s do not.
Careful analysis of all the preclinical and clinical information available on NR confirms it is safe and well-tolerated. There are no data available stating whether or not NMN is safe for human consumption.*
4. NR has 3 FDA safety notifications. NMN has 0.
The only commercially available form of NR, NIAGEN®, has twice been successfully reviewed under FDA's new dietary ingredient (“NDI”) notification program and has also been successfully notified to the FDA as generally recognized as safe (“GRAS”). NMN has not yet been notified to the United States (as NDIN or GRAS).*
5. NR increases NAD by up to 60% in humans. NMN may not.
In this 2018 study, 1000 mg/day of NR increased NAD levels by 60% on average in older adults. There is no published data to show how NMN affects human NAD levels.*
6. NR can enter the cell. NMN may not.
Scientists studying how precursors enter cells have made some interesting observations about NR and NMN. For example, NR uses a unique set of transporters and enzymes to convert directly into NAD within the cell, while NMN is broken down into NR first, outside of cells, before being used to increase NAD. Scientists also found NMN can’t increase NAD as efficiently without those unique NR transporters or enzymes. [1-4]
These experimental findings suggest that NMN, in its supplement form, becomes NR first before entering the cell. Then once inside the cell, it converts back into NMN to make NAD. This is a three-step and rather inefficient process. NR can directly access the cell, so it only requires two steps to begin creating NAD.
7. NR is taken orally. NMN is mostly studied by injection.
Despite NMN being sold as a pill to people, NMN is frequently studied through injections in rodents. In preclinical NR trials, it’s most commonly added to food or water. Plus, in all of NR’s published human trials it was administered in capsule form, which represents the recommended way of taking NR as a vitamin.*
8. NR fits easily into a 300 mg capsule. NMN does not.
One practical consequence of NMN being a larger molecule is that it weighs more than NR. This means fewer NMN molecules fit into a single 300 mg than NR. Fewer molecules result in fewer opportunities to create NAD. Therefore, as a supplement, you would need to take more NMN than NR to get the same cellular energy boost.
There aren’t any human studies comparing NR to NMN (because NMN doesn’t have any clinical trials), but we do have them in animal models. And there the evidence shows that NR is a more efficient way of increasing NAD. [1–4]
NAD is getting a lot of publicity lately for its potential impacts on human health. Recent publications include TIME, Fast Company, The Atlantic, AARP The Magazine, and more. If you think NAD is as important as some leading biochemists and nutritionists believe it is, it’s worth making sure you’re investing in the most effective way to increase NAD. After all, isn’t that why all of us keep up with the news surrounding aging and science? We care about things like that.