NAD+ supplements and mitochondrial health explained

Supplements are big business, worth around $152 billion in 2021. Some estimate that this will almost double by 2028.

As this market grows, so does the pressure to sell new and interesting products. One of the latest additions to this ever-expanding range of options is NAD supplements. 

According to one company that sells these products, they can “support cellular longevity and enhance overall well-being.” Another says they can “contribute to maintaining vitality” and “support youthful cell metabolism.”

These all sound fairly vague. So, let’s dig into the details and get to the bottom of it. First, we’ll cover some of the science to help us cut through the marketing jargon.

What are mitochondria?

Many of you might remember from your school days: Mitochondria are the “powerhouses of the cell.” They are present in almost every cell in your body (only red blood cells don’t have any). 

Mitochondria achieve this through a complex set of chemical reactions — you might dimly remember your teacher mentioning the citric acid or Krebs cycle. 

The unit of energy mitochondria create is adenosine triphosphate (ATP), and it fuels all of your body’s processes — from cellular reactions to flexing your bicep.

So, when mitochondria go wrong, it’s bad news, and we’ll talk a little about mitochondrial diseases later.

What is NAD?

NAD stands for nicotinamide adenine dinucleotide, and it’s a big player in your metabolism. It helps enzymes complete chemical reactions — more than 400 enzymes rely on it to function correctly. 

One of its most important jobs takes place in your mitochondria. NAD helps shift the energy produced during the Krebs cycle into molecules of ATP, which your body can then use.

During the production of ATP in mitochondria, electrons are passed between different molecules, which is called electron transfer. Very simply, the cycle goes like this:

1. NAD+ accepts an electron from the Krebs cycle, which converts NAD+ to NADH. 

2. NADH carries this electron to where it’s needed for the next phase of ATP production. 

3. Once NADH has off-loaded its electron, it becomes NAD+ again.

Then, the cycle starts anew. NAD is known as a co-enzyme, like its popular wellness predecessor Q-10.

NAD also seems to be important in other ways. It helps:

• repair DNA

• manage cell death

• maintain telomeres 

Telomeres are repeated sequences of DNA at the ends of chromosomes. They help protect the ends of DNA from getting damaged or tangled. Every time a cell divides, telomeres get a little shorter. 

So, as we age, telomeres get shorter. When they become too short, the cell can no longer divide and dies.

Quick recap

To summarize the bewildering biochemistry above, mitochondria produce ATP, the energy your body needs to do everything.

NAD, which comes in two forms — NAD+ and NADH — is vital for ATP production. It also seems to be important for healthy aging, maintaining DNA, and more.

Given all of this information, it’s understandable why NAD supplements seem attractive. But do they really work?

Do NAD supplements work?

Often, NAD supplements contain compounds called nicotinamide riboside (NR) or nicotinamide mononucleotide. These are “precursors” to NAD+ — in other words, your body can convert them into NAD+. 

We should also mention that some clinics offer blood infusions of NAD+ or its precursors. To date, there have been no clinical trials in humans. So, we don’t know whether they do anything (or how safe they are).

Scientists have carried out studies on animals, both using intravenous and oral supplementation. Some have produced encouraging results, but we must always interpret animal studies with caution — humans are a different beast.

A small number of trials, however, have recruited humans and mostly focused on oral NR supplements. 

However, many of these didn’t have a placebo group, which makes the results difficult to interpret — you can’t tell whether the benefits are due to the placebo effect or other variables.

Still, these studies do show that NR supplements increase levels of NAD in the blood. This is encouraging, but it doesn’t mean it increases the levels in other tissues. So far, there’s no evidence that it increases levels in muscles, for instance.

And beyond increasing blood levels, they haven’t found any meaningful health benefits. The authors of a review on NR supplements conclude:

“The general finding in human NR trials, especially those concerned with metabolism, is that NR supplementation has very few clinically relevant effects.”

However, they also explain that this field is new. The first human studies on NR were only conducted around 8 years ago. Overall, the authors are upbeat about the potential for these supplements to help some people. For instance, they write:

“NR has shown some promise in the reduction of inflammatory markers in blood, as well as in the treatment of diverse severe diseases  and, potentially, hypertension.”

The severe diseases they mention include heart failure and Parkinson’s disease. However, they also explain that much more research is needed.

There simply isn’t enough evidence to prove they have any benefits. This is why supplement companies use wishy-washy phrases like “contributing to maintaining vitality,” which doesn’t really mean anything.

What should you do?

The take-home message is this: There’s no good evidence that NAD supplements can improve health or help you live longer.

NAD and its related compounds are vital for good health. But we don’t know whether supplements support or benefit health. We don’t even know whether these supplements raise NAD levels throughout your body.

It's also worth remembering that your mitochondria, while important, aren't the only important things in your body. Everything needs to be cared for — there's no point looking after the batteries if the rest of the car is broken.

Perhaps in the future, NAD supplements will be helpful for treating some chronic conditions. But it’s equally likely that they won’t help healthy people.

Similarly, although they seem to be safe in shorter trials, we don’t know what happens when they’re taken over months or years. And we don’t know how they might react with other medications.

So, rather than spending out on supplements with no proven benefits, use your money to support your health in ways that are backed by science: Following a nutritious, plant-heavy diet and keeping active. 

So, by following a healthy diet, you can raise your NAD levels without needing to fork out on supplements.  

Although it sounds like a broken record, the scientific evidence that diet and lifestyle changes can help you live a long and healthy life is impossible to ignore. So that’s the best place to start.