What are NAD supplements and how do they work?

NAD (or NAD+) might not be a nutrient you’ve heard much about before, but it’s fast becoming one to watch.

Searches for NAD supplements are up more than 200% in 2025, with growing interest on Google and TikTok as people look for new ways to support their energy and wellbeing.

But what exactly is NAD, what role does it play in the body, and what does the research say so far? Here’s a guide to help you understand the basics.

What is NAD?

NAD stands for nicotinamide adenine dinucleotide; a natural molecule found in every living cell. It helps your body turn the food you eat into fuel and keeps your cells working smoothly behind the scenes.

In its active form (NAD⁺), supports your cells’ mitochondria in producing the energy your body needs. Mitochondria are tiny structures found in almost every cell, converting nutrients from food and the oxygen you breathe into usable energy. Think of them as the batteries that keep your body going and help your cells do their jobs.

NAD is a naturally occurring molecule that plays a part in:

The body’s normal energy pathways

The natural upkeep of DNA

Supporting everyday cellular processes

Types of NAD supplements

NAD supplements include NAD or ingredients that are linked to the body’s natural NAD pathways. According to Dr Pam Mason, nutritionist for the Health & Food Supplements Information Service “more than 400 enzymes rely on NAD [the molecule] to function properly, and NAD levels decrease with age.”

Because NAD supports these important processes in the body these vitamins and supplements have become popular with people who want to maintain their energy and support healthy ageing.

There are a few different types of NAD supplements, but most fall into two main categories.

NAD⁺ supplements contain the active form of NAD itself. Because these molecules are quite large, the body may not absorb them very well, so more research is needed to understand how effective they are.

NAD precursors include ingredients like nicotinamide riboside (NR) and nicotinamide mononucleotide (NMN). The body converts these into NAD⁺, and they’re some of the most researched forms, often linked to vitamin B3.

You’ll usually find NAD supplements as capsules or powders, sometimes blended with other nutrients that support energy levels.

If you’re thinking about trying one, it’s a good idea to talk to a pharmacist or healthcare professional first, especially if you are pregnant, breastfeeding, take medication or have a medical condition.

What does the research say?

Research into NAD supplements is still in the early stages. Some small studies suggest that certain forms of NAD, like NMN and NR, can increase NAD⁺ levels in the blood, a molecule that helps the body make energy.

Other small studies have looked at things like sleep and signs of ageing, with some positive results, but it’s still too early to say for sure.

As Dr Pam Mason explains: "Some laboratory studies have proved encouraging. Studies in humans have shown that supplements can increase NAD levels in blood, but most have been poorly controlled, making findings difficult to interpret. There is not enough evidence to show clinical benefit in humans.”

At the moment, research suggests NAD supplements can raise NAD⁺ levels, but there isn’t enough evidence to show they provide measurable benefits for ageing, energy or other aspects of health. More long-term research is needed to understand their potential role.

Why do NAD levels change with age?

NAD⁺ levels naturally change as we get older, and factors like everyday stress and lifestyle can influence this. The body’s enzymes, which are natural proteins that help with things like breaking down food and releasing energy, use NAD⁺ as part of their usual activity. Free radicals from normal cell processes or environmental exposure, such as pollution, can also affect these pathways. Lifestyle habits, including how well you sleep, how active you are and what you eat, may play a role too.

Focusing on simple daily habits, such as balanced eating, regular movement and good sleep, can help support your body’s natural energy balance and overall wellbeing.

NAD, ageing and energy

Current research does not show that NAD supplements influence ageing or offer verified health benefits. Ageing is a natural part of life, and no supplement or ingestible has been shown to slow, reverse or alter it.

Supplements should always be seen as an addition to, not a replacement for a balanced and varied diet or a healthy lifestyle.

Other ways to support NAD levels

Lifestyle choices can naturally help maintain NAD activity:

Eat foods rich in Vitamin B3 (Niacin) (such as chicken, tuna, salmon, eggs and mushrooms)

Stay active to support metabolism

Prioritise good sleep and manage everyday stress

These habits help maintain energy balance and support the body’s own NAD processes.