What Is NAD+, and Can It Really Slow Ageing?

Few molecules have had a longevity moment quite like NAD+. It's the science behind a whole category of supplements, the headline ingredient in IV drips, and a favourite of biohackers and longevity researchers alike. With all that noise, it's genuinely hard to tell what's real. So let's do that here: what NAD+ actually is, why it matters as we age, and — honestly — what the evidence does and doesn't yet show. The biology is real and fascinating. The marketing, in places, runs well ahead of it.

What NAD+ actually is

NAD+ (nicotinamide adenine dinucleotide) is a coenzyme — a helper molecule — found in every living cell. It's not exotic; it's fundamental. It does two big jobs ¹.

First, energy. NAD+ is central to the chemical reactions that convert the food you eat into usable cellular energy. It shuttles electrons through metabolism, including inside the mitochondria — the tiny "power plants" of your cells. Without enough NAD+, that energy-production line slows down.

Second, and just as importantly, NAD+ is the fuel for a set of maintenance enzymes that keep cells healthy. These include the sirtuins (often called "longevity enzymes", involved in regulating metabolism and cellular stress responses), the PARPs (which help repair damaged DNA), and CD38 (involved in immune signalling) ¹. Each of these consumes NAD+ to do its work — which becomes important in a moment.

So NAD+ sits at a crossroads: it powers your cells and it supplies the machinery that repairs and maintains them. That dual role is exactly why it's so interesting to anyone thinking about ageing.

Why NAD+ declines with age

Here's the finding that launched a thousand supplements: across many organisms, including humans, tissue and cellular NAD+ levels gradually fall with age ¹. The cellular energy-and-repair currency becomes scarcer precisely when cells could use more of it.

Why does it happen? It's a combination of making less and spending more. Some of the body's NAD+-producing capacity declines, while demand rises — partly because the NAD+-consuming enzymes get busier. As DNA damage accumulates with age, the repair enzymes (PARPs) draw down more NAD+. As low-grade inflammation rises, CD38 activity increases and consumes more still ¹. It becomes a self-reinforcing squeeze.

This is really the cellular-energy face of a couple of the broader hallmarks of ageing — particularly mitochondrial dysfunction and the dysregulation of nutrient-sensing pathways. And the inflammation link is a two-way street: the same chronic, low-grade inflammation we explore in Chronic Inflammation and Ageing helps drive NAD+ down, which is part of why these processes are best understood together rather than in isolation.

Where does NAD+ come from?

Your body doesn't depend on a single source of NAD+ — it both makes and recycles it. Most of your day-to-day supply comes from a recycling route called the salvage pathway, which rebuilds NAD+ from its own breakdown products, topped up by precursors the body converts into NAD+ ¹. Those precursors trace back to the vitamin B3 family — niacin and nicotinamide — found across a normal varied diet in foods like meat, fish, poultry, whole grains and legumes. Small amounts of the trendier precursors, NR and NMN, occur naturally in some foods too, but only in modest quantities.

The practical takeaway is reassuring and slightly deflating at the same time. A balanced diet with enough B3 already gives your body the raw materials it needs to make NAD+ — outright dietary deficiency is rare. But you can't meaningfully "eat your way" to the dramatically higher NAD+ levels the supplements market promises: ordinary food keeps the system running, it doesn't supercharge it. Which brings us to the question everyone actually asks.

The big question: can boosting NAD+ slow ageing?

If NAD+ falls with age and matters this much, the obvious idea is: put it back. This is where the excitement — and the overreach — lives, so it's worth separating the animal evidence from the human evidence carefully.

In animals, the results are genuinely exciting. In laboratory studies, giving NAD+ precursors (molecules the body converts into NAD+, chiefly nicotinamide riboside, NR, and nicotinamide mononucleotide, NMN) raises NAD+ levels and improves a range of age-related measures — metabolism, mitochondrial function and more ¹. In mice, restoring NAD+ can slow aspects of age-related decline. That's a real and promising signal, and it's why serious researchers take NAD+ seriously.

In humans, the picture is more sobering — and this is the part the marketing tends to skip. The most recent comprehensive reviews are consistent: oral NR and NMN are safe and well tolerated over weeks to months, and they reliably raise NAD+ levels in the blood and cells ²³. So far, so good. But when researchers look for clinically meaningful benefits — better metabolic health, vascular function, strength, physical performance — the results are, in the words of a 2026 systematic review, "heterogeneous and often null or endpoint-specific" ³. In plainer terms: the biomarker moves up reliably, but the hoped-for real-world outcomes mostly haven't been demonstrated yet ².

That doesn't mean NAD+ is a dead end — it means the human evidence is still early. Bigger, longer, better-designed trials are exactly what the field is calling for ²³. It's a "watch this space", not a "we have the answer".

What about NAD+ drips and IV?

Because NAD+ is offered intravenously in many wellness settings, this deserves a direct, honest answer. Almost all of the human trial evidence above is for oral precursors (NR and NMN). For intravenous or intramuscular NAD+ specifically, the same 2026 review found no eligible outcome trials testing it for anti-ageing or wellness — only limited short-term safety and biomarker information from a single non-randomised study ³.

That's an important distinction. It means anyone claiming an NAD+ drip is a proven way to reverse or slow ageing is getting ahead of the evidence — because the outcome trials that would support such a claim simply haven't been done. The honest position is that IV NAD+ is popular and appears short-term safe under supervision, but it is not a clinically proven anti-ageing or wellness treatment.

How we think about NAD+ at Cureon

We find the biology genuinely fascinating, and we won't pretend otherwise — but we also won't oversell it. Our NAD+ Revive drip is a doctor-supervised session that people often choose on the weeks they're running on empty, and many tell us they feel more energised and clearer afterwards (here's what to expect from an IV drip if you're new to them). We're candid about what that is and isn't: it's an experience some people genuinely value, not a proven treatment that will slow your ageing — and the formal trial evidence for IV NAD+, for both anti-ageing and wellness, is still limited ³. A doctor confirms whether it's appropriate for you before anything goes ahead.

And the unglamorous truth sits underneath all of it: the most reliable way to support your NAD+ biology isn't a drip or a pill — it's the same set of foundations that influence so many of the hallmarks of ageing at once. Regular exercise, in particular, supports healthy NAD+ metabolism and mitochondrial function as a welcome side-effect of everything else it does. Those basics remain the part of the longevity story with the strongest evidence behind it.

Common questions

Does NAD+ really decline as we age? Yes. Research consistently shows that NAD+ levels fall in tissues and cells with age across many organisms, including humans. That decline is well established — it's what to do about it that's still being worked out.

Do NAD+ supplements (NR or NMN) actually work? They reliably and safely raise NAD+ levels in people over weeks to months. But proven, clinically meaningful benefits — for things like strength, metabolism or performance — remain limited and mixed in human trials so far. They raise the marker; the real-world payoff is not yet demonstrated.

Are NAD+ IV drips proven to slow ageing? No. There are no outcome trials showing intravenous NAD+ slows ageing or improves wellness — only short-term safety and biomarker data. Be cautious of any clinic that promises otherwise.

Is taking NAD+ safe? Oral precursors have been generally well tolerated in trials lasting weeks to months. Intravenous NAD+ should only be given under medical supervision, with a doctor confirming it's suitable for you.

What's the best way to support my NAD+ naturally? The foundations — and especially regular physical activity, which supports NAD+ metabolism and mitochondrial health as part of its wide-ranging benefits. It's free, proven, and helps far more than NAD+ alone.

Key takeaway

NAD+ is a real, essential molecule — it powers your cells and fuels the enzymes that repair them, and it genuinely declines with age. That makes it one of the most interesting targets in longevity science, and the animal evidence is legitimately exciting. But honesty matters: in humans, supplements safely raise NAD+ levels while clinical benefits remain early and mixed, and IV NAD+ has not been tested in anti-ageing or wellness outcome trials at all. Enjoy the science, stay sceptical of the hype — and remember that the foundations still do the heavy lifting.