NAD+ is heralded by celebrities as the fountain of youth, but there’s no solid evidence to back that up.Though NAD+ shows some early promising benefits in animal studies and some human trials, there isn’t really enough data yet.
TL;DR: NAD+ has some promising research but we honestly don’t have any solid scientific data to support the claims that celebrities and influencers are making.
What Is NAD+?
NAD+ is short for nicotinamide adenine dinucleotide. It’s a coenzyme that our bodies make and need to function. Coenzymes are molecules that bind to enzymes to help speed up reactions. To explain what that means and why it matters, we’re about to go a little heavy on the jargon (sorry!), but I’ll try to make it as painless as possible.
The mitochondria, aka the powerhouse of the cell, use a lot of NAD+. NAD+ is used by enzymes (molecules in your body that make all the daily chemical reactions in your body happen). A lot of NAD+ is used in the Krebs Cycle. Basically, NAD+ gets converted to a molecule called NADH through enzyme magic and creates ATP (your body’s main form of energy) but it also creates lots of molecules that are used later to create even more ATP. If the mitochondria are the powerhouse of the cell, NAD+ is the fuel that keeps the lights on!
Your body makes NAD+ from the amino acid tryptophan, which is found in lots of foods, but especially in turkey, chicken, eggs, beef, fish and soy. Vitamin B3 (niacin) is also a NAD-building block. Precursor forms, which are other building blocks for NAD+, have also been studied and have been found to boost NAD+ levels in the body. These include:
🔸 NMN (nicotinamide mononucleotide)
🔸 NR (nicotinamide riboside)
So we know that NAD+ is very important for a bunch of metabolic functions. We also know levels of NAD+ decline with age. So, would supplements actually help us function and age better? Well, it’s a little unclear. One of the main problems with taking a supplement like NAD+ is that while the supplement might increase the NAD+ levels in your blood, it’s not completely clear that it’s getting into your body’s cells (in science speak, we don’t know how “bioavailable” it is), where it would be used. Another problem is that we don’t know which dosage or form of NAD+ would need to be taken. In studies with mice and rats, too much NAD+ caused adverse effects like liver and kidney problems.
What does the science say?
Most NAD+ studies have been done in mice and test tubes (for example, the above meta-analysis about NAD+ adverse effects primarily features outcomes in mice and rats). While some show promising results, the research is mixed and the results may not apply to humans.
Some animal studies show a potential for NAD+ to be helpful. For example, one study in mice shows that NAD+ can help with diabetic neuropathy. But not all research findings in animals have been positive. One study showed that while giving mice NAD+ supplements after an ischemic stroke (when a brain doesn’t get enough oxygen) seemed to help them get better, giving the mice NAD+ before the stroke actually made them worse.
As for research in humans, findings have also been mixed. Meta-analyses of studies indicate that people didn’t have bad adverse reactions to the supplements, and there were no real changes in things like insulin sensitivity or blood pressure. There might be some decrease in inflammatory markers with supplementation. In one of the recent human trials looking at one of the NAD+ building block molecules, 90 individuals with peripheral artery disease (a disease where it’s harder for blood to get to your limbs), showed that the precursor helped those individuals walk faster. That’s promising, but the bottom line is that larger studies and studies that follow participants for long periods of time are needed to know if there’s any health benefit from taking an NAD+ supplement or any NAD-boosting form. Some corporations are looking into NAD+ as a potential supplement but, as other Nerdy Girls have discussed in other posts, supplements don’t have to have proven health benefits to be marketed to the public.
As far as supplements go, we just don’t have enough information to say that they are going to do much at all. So far, no safety concerns have been found from oral forms, but as always, it’s best to discuss with your clinician before taking any supplement. The FDA did issue a warning about the injectable forms of NAD+, so that’s something to keep in mind! And it’s always important to note that with supplements, efficacy and safety can be dubious. Choosing supplements verified by third-party testers is key. Check websites like NSF.org or the USP database to find brands that use third-party testing. Hopefully, future research will give us clearer answers about whether NAD+ is truly a ‘fountain of youth.’ For now, the biggest downside might just be the hefty price tag–without solid evidence that it actually works.
For evidence-based tips for boosting health as you age, the NIH has an awesome list of things you can do!
Further reading:
Possible adverse effects of NAD+
