How to choose an NAD+ supplement in the UK

To choose an NAD+ supplement in the UK, start with the ingredients list: find out whether the product contains NAD+ itself or a precursor such as nicotinamide riboside (NR) or NMN, and how many milligrams of that one ingredient a daily serving gives you. Then ask for the certificate of analysis for the batch you would receive, check that the product is sold as a food supplement with no disease claims, find out how it has to be stored, and compare cost per milligram of the active ingredient.

A search for "best NAD supplement UK" mostly turns up lists of brands. This page names none, because the best NAD+ supplement for you depends on your answers to the questions below. We sell one product, an injectable NAD+ kit, so we have an interest here, and the last section puts our kit through the same checks as everything else.

Does it contain NAD+, or a precursor?

Plenty of products with NAD+ in the name contain a precursor, a smaller molecule the body uses to make NAD+. The common ones are NR, NMN, nicotinamide and nicotinic acid (Migaud et al., 2024). Front-of-pack phrases such as "NAD+ support" or "NAD+ complex" can mean any of these, or a blend, and only the ingredients list settles it.

NAD+ tablets and NAD+ capsules that do contain NAD+ run into the way the gut handles it. NAD+ is a phosphorylated nucleotide, and a 2024 review notes that, as a general rule, these do not cross cell membranes. NAD+ in the gut is broken down to NR or smaller pieces before it is absorbed, most of it as nicotinamide or nicotinic acid (Migaud et al., 2024). The NAD+ in a capsule is therefore unlikely to reach your bloodstream intact.

NR and NMN have far more human research behind them than swallowed NAD+ does, although that research is still modest, and our guide to NMN versus NAD+ goes through what those trials measured.

What route does it use, and what evidence is there for it?

For oral NR, the best-known trial gave 30 healthy middle-aged and older adults six weeks of 1,000mg a day and six weeks of placebo. NAD+ in their blood cells rose by about 60% compared with placebo, and the authors wrote that the group was too small to establish NR's wider safety profile at that dose (Martens et al., 2018). A 2023 review of all 25 published human NR studies concluded that oral NR had "displayed few clinically relevant effects" and that the literature tends to exaggerate the effects it does report (Damgaard and Treebak, 2023). For NMN, a trial of 250mg a day for 12 weeks in 42 men aged 65 and over found higher blood NAD+ than in the placebo group (Igarashi et al., 2022). Both trials measured NAD+ in blood, and a higher reading says nothing on its own about how you will feel.

Injected NAD+ has less behind it. In a 2019 pilot, eight men received 750mg of NAD+ by intravenous drip over six hours and three received saline; plasma NAD+ did not rise at all for the first two hours, and no adverse events were recorded (Grant et al., 2019). The 2024 review says intravenous NAD+ "has become fashionable" although its authors knew of no scientific literature testing its effects (Migaud et al., 2024). We looked for a published controlled trial of NAD+ injected with a pen or syringe, the route our own kit uses, and did not find one.

How much is in a serving, and how is it stated?

A food supplement label in the UK has to give the recommended daily dose with a warning not to exceed it, and the amount of each substance "with a nutritional or physiological effect" (Food Standards Agency). On the label itself, check:

• whether the milligram figure on the front is per capsule or per daily serving, since a pack can print one number and tell you to take two capsules
• whether a blend lists each ingredient's amount; a single figure for a blend is the weight of the whole mix and does not say how much of it is NR or NMN
• which molecule the milligrams refer to: NR sold in Great Britain must be labelled as nicotinamide riboside chloride (Food Standards Agency register), a salt, and a milligram of that salt is a different amount of material from a milligram of NAD+

More is not automatically better. Nicotinamide riboside chloride is authorised in England, Scotland and Wales for food supplements at up to 300mg a day for adults, with a lower limit in pregnancy and breastfeeding (Food Standards Agency register). The NR trial above used 1,000mg a day, more than three times what a food supplement here may recommend.

Has the batch been tested, and can you see the certificate?

A certificate of analysis (COA) is a laboratory's report on one batch. A specification sheet, which lists the results a product is supposed to meet, is a different document. Ask for the COA for the batch you would receive, and check it for:

• a batch number that matches the one printed on your pack
• the name of an independent laboratory and the date of the test
• what was measured: identity, purity and, ideally, content (the milligrams present per capsule or vial)
• contaminant results such as heavy metals or microbial counts, where the lab ran them

Purity is usually measured by HPLC (high-performance liquid chromatography), which separates a sample into its components so each can be measured. An HPLC purity figure is relative. It is the target compound's share of everything the detector picked up, and material the detector does not respond to, such as water, salts or leftover solvent, can go unseen. One published example is a commercial sample marketed as 97% pure by chromatography that turned out, measured another way, to be 78.4% of the stated compound by weight, mostly because of solvent the first method missed (Pauli et al., 2014). A purity figure and a content figure answer different questions, and a good certificate gives you both.

Labels and contents can be a long way apart. When researchers tested 18 NMN supplements bought online, in pharmacies or from manufacturers, three contained no NMN the lab could detect (Sandalova et al., 2024). NHS pharmacy guidance also warns that "the existence of a Certificate of Analysis, or a document purporting to be one, does not prove suitability for use" (NHS Specialist Pharmacy Service).

Is it legally sold as a food supplement in the UK?

NAD+ supplements are sold under food law, and a food supplement is defined as a concentrated source of a nutrient or other substance, sold in dose form to supplement the normal diet (Food Standards Agency). The label has to say "food supplement". A product labelled "dietary supplement", the American term, may have been packed for another market.

NHS pharmacy guidance says food manufacturers are not required to prove the safety or efficacy of their products before placing them on the market, and supplements do not have to be made to the stricter standards that apply to medicines (NHS Specialist Pharmacy Service).

Novel foods are the exception. Anything not eaten to a significant degree in the UK or EU before 15 May 1997 needs authorisation before it can be sold in Great Britain (Food Standards Agency). Nicotinamide riboside chloride has that authorisation (Food Standards Agency register). For NMN, the Food Standards Agency's register lists an application to authorise beta-nicotinamide mononucleotide as a novel food as "in progress", at the risk assessment stage, as of September 2026 (Food Standards Agency application register). It is fair to ask an NMN seller how its product is on sale in Great Britain while that application is open.

Treat "research use only" or "not for human consumption" as a stop sign on anything marketed to people with doses and routines. Those words mean the seller does not stand behind the product as something to take, and it will not carry the daily dose and warnings a food supplement label must show.

Does it need to be kept cold?

Every food supplement label has to carry storage instructions (Food Standards Agency), and for capsules and powders those are usually enough. Liquids need more care, because NAD+ in solution breaks down. In a 2024 laboratory study, an NAD+ solution in one common buffer had degraded almost completely after 43 days at 19 °C, while in another it lost about 4%; for the closely related NADH, a rise from 19 °C to 25 °C sped up the breakdown (Wolfe et al., 2024). Those were laboratory buffers, but a liquid NAD+ product should state a storage temperature, and the seller should be able to tell you how it stays in that range in transit.

How do you compare prices fairly?

Take the milligrams of the active ingredient (NAD+, NR or NMN, not the capsule weight or the whole blend) in one daily serving, multiply by the number of daily servings in the pack, and divide the price of the pack by the result. A pot of 60 capsules holding 250mg of nicotinamide riboside chloride each contains 15,000mg, so its price divided by 15,000 is the cost per milligram.

The figure is only fair between like and like: NR with NR, NAD+ with NAD+. Route matters too. Swallowed NAD+ is broken down in the gut before it is absorbed (Migaud et al., 2024), so a milligram swallowed and a milligram injected are not directly comparable, and a kit that includes a reusable device is not priced like a pot of capsules. Cost per milligram shows you which products look out of line; the rest of this checklist tells you whether the difference is justified.

Which claims should you distrust?

Under UK medicines law, a product "presented as having properties of preventing or treating disease in human beings" counts as a medicine (MHRA). Government guidance on food supplements says they are not medicinal products and are not intended to treat or prevent diseases (Food Standards Agency). A supplement advertised as a remedy for a named condition is therefore either an unlicensed medicine or a food making claims it is not allowed to make.

Other claims to be wary of:

• a percentage rise in NAD+ with no named study behind it, or with a study of a different molecule, dose or route
• "clinically proven" where the studies were on an ingredient and never on the product
• before-and-after photographs and customer results, which no seller can standardise or check
• a purity figure with no certificate or laboratory attached

The research on NAD+ is mostly early, and our guide to NAD+ benefits and side effects sets out what has been studied so far.

Where our kit sits on this checklist

Our NAD+ kit contains 1000mg of NAD+ itself as a pre-mixed solution in a sealed vial, with a reusable metal auto-injector, single-use needles and alcohol wipes. Every batch is tested by an independent laboratory by HPLC to at least 99% purity, and that batch's own certificate of analysis is in the box. It is made in the UK and sold as a food supplement, not a licensed medicine. The sealed vial is kept refrigerated at 2 to 8 °C.

Against the checklist, that answers the first question (it is NAD+ itself), the dose question (the milligrams on the label are NAD+), the certificate question and the storage question. The testing section applies to us as much as to anyone: HPLC purity is a relative figure, so what matters is the batch's own certificate of analysis, which we include in the box.

There are good reasons to choose something else. If you would rather not inject yourself, an oral product avoids needles altogether. If you want the route with the most published human research, that is an oral precursor, NR above all, and we found no controlled trial of NAD+ given by pen injection. The vial also needs space in a fridge. On cost per milligram, an injectable kit is unlikely to come out ahead of capsules.

Speak to a doctor before starting if you are pregnant, breastfeeding, taking prescribed medication or under medical supervision. The kit is not for anyone under 18. Our page on buying NAD+ in the UK covers the kit in more detail.