NAD+ supplements: what the evidence actually shows
Quick answer
NAD+ is a coenzyme every cell needs, and levels fall with age. Oral precursors like NMN and NR are food supplements with limited evidence; NAD+ injections are unlicensed treatments available only after a clinical suitability check. Neither is provided by the NHS or endorsed by NICE.
What is NAD+, and why does it matter?
Nicotinamide adenine dinucleotide, or NAD+, is a coenzyme found in every cell in the body. It plays a central role in turning food into usable energy, supporting DNA repair, and helping cells communicate with each other. Without it, the basic chemistry of being alive would not work.
NAD+ levels are not fixed. Research consistently shows they decline with age, and lower levels have also been linked to poor sleep, high alcohol intake, and a diet low in key nutrients. This decline is the reason NAD+ has become a popular target for supplements, injections and IV drips marketed under the banner of energy, focus and healthy ageing.
Some of the early laboratory interest came from studies on a family of proteins called sirtuins, which rely on NAD+ to function and have been linked in animal research to cellular repair and stress-resistance processes. That laboratory story is part of why NAD+ crossed over from academic biochemistry into consumer wellness marketing, well ahead of any large human trial confirming a real-world benefit.
What is far less settled is whether raising NAD+ levels artificially, through a tablet, capsule or injection, actually produces a meaningful benefit for a generally healthy person. That question is where the evidence gets more complicated.
The different ways NAD+ is sold
NAD+ itself is a large molecule that is broken down almost completely if swallowed, so oral products do not contain NAD+ directly. Instead, most tablets and capsules contain a precursor, commonly nicotinamide riboside (NR) or nicotinamide mononucleotide (NMN), which the body can convert into NAD+ through several chemical steps.
Injectable NAD+ products bypass digestion entirely, delivering the coenzyme into the muscle or under the skin. My London Pharmacy's own range reflects this split: Liposomal NAD+ Capsules are an oral precursor product, while the NAD+ Injection Kit and NAD+ Pen are prescriber-led injectable options, available only after a clinical suitability check.
You may also see NAD+ marketed as an IV drip, a patch, or a nasal spray. The underlying question is the same for all of them: how much of the active ingredient actually reaches the bloodstream intact, and for how long, is not consistently established across products, which is one reason a clinician review before starting is worthwhile rather than optional.
Each route has a different evidence base and a different regulatory status, which is worth understanding before choosing between them.
What the evidence actually shows
Most of the striking results for NAD+-boosting compounds come from animal studies, particularly in mice, where interventions have shown improvements in metabolic markers, mitochondrial function and measures of physical performance. These findings are the basis for a lot of the marketing language around NAD+ products.
The picture in humans is thinner. A systematic review of NAD-boosting interventions published in early 2026 pooled a much larger number of human and animal studies, and found that while these compounds reliably raise blood NAD+ levels, evidence for clinical benefits such as improved energy, cognition or physical performance in humans remained limited and inconsistent across studies. Most human trials to date have also been small and relatively short, which makes it hard to draw firm conclusions about longer-term effects.
Part of the difficulty is what researchers are actually measuring. Showing that a supplement raises a blood marker, in this case NAD+ itself, is a much lower bar than showing it changes how someone feels or functions day to day. A number of the more positive human results relate to the blood marker rather than to a patient-reported outcome such as fatigue or cognitive performance, and results that hold up well in a mouse do not automatically translate to a person, given differences in metabolism, dosing and lifespan between species.
In short: raising your NAD+ level is achievable. Whether that translates into a benefit you would actually notice is not yet established by strong human evidence.
The UK regulatory picture
Oral NAD+ precursor products, such as NR and NMN capsules, are typically sold and regulated as food supplements rather than medicines. Under the GB Nutrition and Health Claims Register, no health claims relating to ageing, metabolism, cognition or cardiovascular health are currently authorised for these ingredients, which is why compliant sellers describe them in general terms rather than with specific promises.
NAD+ injections sit in a different category. They are not licensed medicines: the MHRA has not approved NAD+ for any therapeutic indication, and it does not appear in the British National Formulary. Where it is prescribed, it is typically supplied as an unlicensed "special", meaning a pharmacist or prescriber takes on additional responsibility for assessing that it is appropriate for a specific patient, having reviewed their history. NICE has not issued guidance on NAD+ injections, and they are not available on the NHS.
None of this means NAD+ products are automatically unsafe. It does mean the strength of any marketing claim attached to them, especially one promising rapid or dramatic effects, is worth treating with real scepticism.
Safety and who should be cautious
Reported side effects with NAD+ precursor supplements are usually mild: nausea, diarrhoea, flushing and headache, most often at higher doses. NAD+ injections carry the additional, generally low, risks that come with any injection: injection-site soreness or redness, a warm or flushed sensation during administration, and a small risk of infection or allergic reaction if hygiene standards are not followed properly.
Long-term safety data, beyond roughly a year of use, are limited for both routes. Anyone with diabetes, liver disease or a bleeding disorder, or who is taking statins or other regular medication, should discuss NAD+ supplementation with a GP or clinician first rather than starting on their own.
Because injectable NAD+ is unlicensed, quality and sterility can vary considerably between providers. Sourcing it only through a registered pharmacy or prescriber, rather than an unregulated clinic, is one of the more meaningful safety decisions you can make if you are considering this route.
For oral precursor supplements, it is worth checking that the seller can point to independent batch testing or a certificate of analysis for the product. Supplement manufacturing is not held to the same standard as licensed medicines, so this kind of quality evidence is a reasonable thing to ask a seller for before choosing a product.
Oral NAD+ precursors vs NAD+ injections: how they compare
The two routes are not interchangeable, and the right starting point depends on what you are trying to achieve and how comfortable you are with an unlicensed treatment route.
| Oral precursor (NMN/NR) | NAD+ injection | |
|---|---|---|
| Regulatory status | Food supplement; no authorised UK health claims | Unlicensed medicine, supplied as a "special" after assessment |
| How it is taken | Swallowed daily as a capsule | Injected into muscle or under the skin |
| Access | Sold without a prescription | Requires a clinical suitability check |
| Human evidence for benefit | Limited; mostly small, short trials | Limited; mostly small, short trials |
| Common side effects | Nausea, flushing, headache | Injection-site soreness, flushing, nausea, headache |
Is a NAD+ consultation right for you?
A clinician-led NAD+ consultation is not about promising a transformation. It is a chance to talk through your health history, current medication and reasons for considering NAD+, so that a pharmacist or prescriber can advise whether a product, and which one, is appropriate, and for the injectable route, prescribe it as an unlicensed special where suitable.
That conversation typically covers any existing conditions, other medication you take regularly, and what you are hoping to notice, so expectations stay realistic rather than shaped by marketing. Because the injectable route is unlicensed, a suitability check before the first dose, and a way to raise concerns afterwards, matter more than they would for an established, licensed treatment.
If you are simply looking for a general energy or wellbeing boost, it is worth having ordinary explanations ruled out first, such as poor sleep, low iron, thyroid problems or vitamin D deficiency, since these are more common causes of fatigue and are usually straightforward to test for and treat.
Frequently asked questions
Does NAD+ actually work?
Raising your NAD+ level with a precursor supplement or injection is achievable, but strong human evidence that this produces a noticeable benefit, such as more energy or better cognition, in generally healthy people is still limited. Most of the more striking results come from animal studies rather than large human trials.
Are NAD+ injections legal in the UK?
Yes, but they are unlicensed. NAD+ injections do not have MHRA approval for any condition, so when a pharmacist or prescriber supplies one, it is dispensed as an unlicensed "special" after an individual suitability check, not as a licensed medicine.
What is the difference between NAD+ and NMN or NR supplements?
NAD+ itself is broken down if swallowed, so oral capsules contain precursors instead, usually nicotinamide mononucleotide (NMN) or nicotinamide riboside (NR), which the body converts into NAD+ through several steps. Injections can deliver NAD+ more directly.
Can I get NAD+ treatment on the NHS?
No. NAD+ supplements and injections are not recommended by NICE and are not provided by the NHS. They are only available privately, either as a food-supplement purchase or through a prescriber-led consultation for the injectable route.
What are the side effects of NAD+ injections?
The most commonly reported effects are injection-site soreness or redness, flushing, nausea and headache. Long-term safety data beyond around a year are limited, so anyone with diabetes, liver disease or another ongoing health condition should get clinical advice before starting.
Who should avoid NAD+ supplements or injections?
Anyone who is pregnant or breastfeeding, has significant liver or kidney disease, or is unsure how NAD+ might interact with existing medication should speak to a GP or clinician before starting, rather than self-administering an unlicensed product.