What’s the best, most effective way to take NMN?
Orally? Sublingually (melting it under the tongue)?
Or is NMN only available through injection?
Some people claim that NMN cannot be taken orally. Others claim you have to take it sublingually and that just swallowing a pill is not going to cut it.
These claims are based on outdated information.
Orally-taken NMN is absorbed well
Recent research shows that NMN can be taken orally. You also don’t have to take NMN sublingually: you can take it orally. NMN is well-absorbed taking it by mouth.
In earlier studies, NMN was injected directly into the peritoneal (abdominal) cavity in mice. Many people inferred from this that NMN cannot be administered orally.
However, more recent studies show that when NMN is added to the drinking water or chow of mice, they absorb the NMN very well.
The NMN ends up in the bloodstream, and increases NAD+ levels in the cells of mice (NMN is converted into NAD+, the molecule that is partly responsible for the health effects of NMN, given NAD+ is an important cofactor for sirtuins and PARPs, proteins that repair DNA and reduce inflammation, among other effects).
Also, the mice consuming the NMN in their drinking water or chow experienced all kinds of health benefits, like improved blood vessel health, endurance, insulin sensitivity, body weight, immune function, bone density, eye function and mitochondrial metabolism (R,R,R,R).
NMN can be absorbed by cells
It was also previously thought that NMN could not be absorbed directly by the cells.
It was thought that NMN could not cross the cell membrane intact in order for the cells to take it up: NMN first needed to be converted into NR outside the cells, and then the NR would be taken up by the cells (it would cross the cell membrane), to be subsequently converted back into NMN inside the cells.
Recent research shows that there are, however, NMN transporters in the cell membrane, that can take up the NMN directly (R,R). Scientists believe it is very likely that humans even have various other NMN transporters.
NMN is absorbed by the gut and stable in the blood, contrary to NR
The uptake of NMN into cells is in fact distracting us from something much more important: does NMN actually ends up in the blood circulation, and is it stable enough in the blood? (So it can be taken up into cells?)
NMN is stable in the gut and absorbed very well.
Interestingly, NMN is much more stable than NR (nicotinamide riboside) in both the gut and blood.
Most NR already in the gut is converted into nicotinamide. The little NR that is absorbed from the gut into the bloodstream is immediately broken down in the liver into nicotinamide before it reaches the systemic circulation.
Of course, given nicotinamide is also a precursor to NAD+, NR can increase levels of NAD+. But, NR does this indirectly (in other words, one could also take nicotinamide to achieve almost a similar effect).
In contrast, NMN seems to stay intact for much longer in the gut and blood.
NMN is experimented with in various different species
We know that not only mice, but also other animals, such as horses, can take up orally-provided NMN and subsequently experience various health effects due to the NMN (studies not yet published).
Famous NMN researchers, like professor David Sinclair from Harvard University, take NMN orally. For example, David Sinclair adds his NMN every morning to his breakfast yogurt, as he explains in his book “Lifespan“.
In summary, NMN can be taken orally. It is absorbed in humans by the gastrointestinal system, and reaches organs and cells. We shouldn’t be too surprised by this, given NMN is a small and relatively stable molecule.
So enjoy your NMN in your food or in a pill, no need for pricier sublingual tablets or even worse, needles!