Since we first started selling sublingual NMN in 2017, we have heard from thousands of customers that they notice an immediate effect from our sublingual NMN and NAD+, and more long lasting results from our sublingual products vs standard capsules.
Why capsules? Aren’t NMN, NAD, and NR are all metabolized to NAM in the stomach and liver?
It is true that the 2018 Rabinowitz study found that very little, if any, NMN or NR make it past the liver into the bloodstream. However, this recent study found some NMN (but not NR) can be transported directly through the cell membrane and converted to NAD+ by the newly discovered SLC12a8 enzyme inside the small intestine.
So the SLC12a8 transporter means NMN capsules are as effective as Sublingual?
No. The quantity that is absorbed by the SLC12a8 enzymes is a small fraction of the total. Testing to quantify how much has not yet been published, but there is much indirect evidence and researchers generally believe it is less than 10%. For example, this research by Sam Trammell shows a slight difference between the amount of NR that reaches the liver vs that of NMN, as does the research by Rabinowitz. The percentage of NMN diverted to NAD+ in the intestines before reaching the liver, is just barely noticeable.
“It is important to note that the discovery of an NMN transporter by no means diminishes the importance of uptake via dephosphorylation.”
There is hope Slc12a8 can be useful in future products
Future products may soon hit the market that target this pathway to help solve the bioavailability problem of NMN capsules. According to the study:
“Dr. Imai’s lab already has identified small molecules that can stimulate production of the Slc12a8 NMN transporter, applied for patents, and licensed this technology to a company in Japan.”
Increasing uptake by SLC12a8 NMN transporter
Researchers like Dr. Sinclair are exploring methods to increase uptake by SLC12a8. Sodium is thought to be required, and making it more available may be key.
Sodium for increased uptake
Dr. Huzienga is a well-known doctor who has conducted recent trials treating COVID-19 patients with an NMN cocktail—achieving a 100% success rate so far. (See here and here.) On advice from Dr. Sinclair, he uses Sodium Chloride to increase the uptake of NMN by SLC12a8. He also includes TMG to increase methylation and zinc to increase immunity.
Sodium Bicarbonate instead of Sodium Chloride
While Dr. Huzienga has been using Sodium Chloride (table salt) in his NMN cocktail for treating Covid 19, our team has found Sodium Bicarbonate to be a better alternative for long term usage, as many people are trying to limit their salt intake.
Delayed Release Capsules
Reaching the small intestines intact is critical to maximize uptake. Our Delayed Release Capsules are engineered to make it through the harsh, acidic environment of the stomach without being degraded. They release their payload only when they reach the alkaline environment of the small intestine.
The Bottom Line
We believe sublingual delivery enables more NMN to reach the bloodstream without being degraded. However, some people are used to taking capsules and we are confident that our SLC NMN™ capsules are better than any other NMN capsule. Besides the increased utilization of the SLC12a8 enzyme, the inclusion of TMG and Zinc restore methyl groups and strengthen immunity.