The NMN market has a serious purity problem

Let's start with the facts, because they are uncomfortable for most of the UK supplement industry.

A 2024 peer-reviewed study published in Food & Nutrition Research tested 18 NMN supplements purchased from online retailers and found that a significant number contained substantially less NMN than stated on the label — in some cases, the actual NMN content was undetectable by HPLC testing. The most common substitute? Plain B3 Nicotinamide — a compound that costs a fraction of real NMN and looks completely identical in a capsule.

This is not a fringe problem. It is mainstream. And it is happening right now in the UK market.

So when you pay £20, £30 or £40 for an NMN supplement — how do you know what is actually in the capsule you are swallowing?

Holland & Barrett — What They Actually Sell

Holland & Barrett does stock NMN — but not their own brand. They stopped selling own-label NMN following regulatory discussions and now list Charava NMN 500 Liposomal as a third-party brand through their platform.

This is actually a more interesting story than simply "H&B sell NMN." The UK's largest high street supplement retailer looked at the NMN market and decided they did not want to put their own name on the product. They are comfortable listing a third-party brand. They are not comfortable owning the supply chain, the testing, or the credential themselves. That is a commercial decision worth noting.

What does Charava claim? Charava state their NMN is 99.6% pure, third-party tested in the USA, with Certificate of Analysis available on request. Their manufacturing facilities are GMP-certified. These are legitimate credentials.

What Charava does not publicly state: The specific name of the independent testing laboratory used for each batch. "Third-party tested in the USA" is a meaningful claim — but it is less specific than "Eurofins HPLC tested, batch by batch, COA available." There is a meaningful difference between those two statements.

Additionally, Charava's declared purity is 99.6% — compared to our independently Eurofins-verified 99.94% for capsules. Both are high-purity NMN. But the numbers are different, and the verification method is different.

Boots — What Are They Actually Selling?

Boots does stock NMN. Specifically, they stock NMN Bio NMN 500mg — a third-party brand, not a Boots own-label product. Boots is the retailer, not the manufacturer or the tester.

NMN Bio states that their product is "third-party tested and packaged in a GMP & ISO9001-certified UK facility." That is a positive statement. GMP (Good Manufacturing Practice) certification and ISO9001 quality management are legitimate credentials. We are not disputing them.

But here is what is not publicly stated on the Boots product listing or on NMN Bio's own site at the time of writing:

• The name of the specific independent testing laboratory used for each batch
• Whether the testing laboratory is a globally recognised independent analytical lab (such as Eurofins)
• Whether a Certificate of Analysis is available on request for the specific batch sold through Boots
• The purity percentage confirmed by independent HPLC testing for each batch

GMP certification tells you the facility meets manufacturing standards. It does not independently verify the purity of the specific batch of NMN you are receiving. Those are two different things.

To be completely fair: NMN Bio may have batch-level COAs available. If they do, and the lab is independent and named, that is good practice. But the information is not prominently available on the Boots listing where most buyers will encounter the product — and most buyers will not know to ask for it.

What Eurofins Testing Actually Means

Eurofins Scientific is one of the world's largest independent analytical testing organisations. Over 900 laboratories across 50+ countries. They test food, pharmaceuticals, environmental samples and supplements for governments, pharmaceutical companies and supplement brands worldwide.

When we say our NMN is Eurofins HPLC tested, we mean:

• A sample from the actual batch is sent to an Eurofins laboratory — independently, not to our own facility
• Eurofins uses High Performance Liquid Chromatography (HPLC) — the gold standard method for identifying and quantifying compounds in supplement powders
• The test confirms compound identity — that the compound is actually NMN and not B3 Nicotinamide or another substitute
• The test confirms purity percentage — our NMN powder is confirmed at 99.9%+ and our capsules at 99.94%
• A Certificate of Analysis is issued by Eurofins — not self-certified, not issued by the manufacturer
• The COA is available on request for every batch

This is the standard we hold ourselves to. Not because we are required to. Because when you are selling a product in a market where fake and adulterated products are common, the only credible response is transparent, named, independent verification.

The Comparison — Side by Side

Table based on publicly available information at time of writing — April 2025. Information may change. We encourage independent verification of all claims.

How to Verify Your NMN at Home — The Three Tests

Regardless of where you buy your NMN — whether from us, from Boots, or from any other supplier — you should do these three checks with every batch you receive. A COA is a document. These tests are physical evidence.

👅 Test 1 — The Taste Test (Most Reliable)

Open one capsule. Place the contents directly under your tongue. This is the single most reliable purity test you can do at home — and it doubles as the optimal absorption method.

Why does this work? Pure NMN has a distinctive molecular structure that produces a specific zesty taste profile. B3 Nicotinamide — the most common substitute — tastes intensely bitter by comparison. This difference is unmistakable once you know it. A certificate can be shared between batches, reused from a previous test, or simply not represent the product in your capsule. The taste test cannot be faked.

💊 Test 2 — The Capsule Size Test

Look at the capsule before you open it. A Size 0 capsule holds approximately 530mg — the correct capacity for 500mg of pure NMN with virtually no room for fillers. A Size 00 capsule holds approximately 700mg — if it is labelled as 500mg NMN, the extra 170–200mg is filler.

At one capsule per day, a Size 00 capsule filled with 500mg NMN and 200mg filler means you are consuming up to 6 grams of undisclosed filler per month at NMN prices. That is filler you are paying for, filler you did not ask for, and filler the seller did not tell you about.

Our capsules are Size 0. Only. Every time. Across the entire NMN range.

⚠️ Test 3 — The Water Test (Don't Bother)

You may have seen sellers dropping NMN powder into water as a purity test. This proves nothing. Maltodextrin, glucose, starch — all common fillers — dissolve in water completely indistinguishably from pure NMN. B3 Nicotinamide dissolves in water and looks identical. If a seller is promoting the water test as proof of purity, the obvious question is: why won't they let you do the taste test instead?

Why We Started Eurofins Testing in the First Place

We have been importing and supplying NMN in the UK since 2016. We were one of the first UK suppliers in the market. In those early years, the fake NMN problem was already emerging — but the testing infrastructure to expose it publicly was limited.

As the market grew, so did the problem. More sellers. Lower prices. No way for buyers to distinguish real NMN from substitutes through packaging alone. We watched cheap B3 Nicotinamide get repackaged and sold at NMN prices. We watched sellers use Size 00 capsules and leave buyers with hundreds of milligrams of undisclosed filler per day. We watched water test videos go viral on TikTok — a test that literally cannot distinguish pure NMN from the cheapest possible substitute.

Our response was to get Eurofins. An independent, globally recognised, named laboratory. Batch by batch. COA available on request. Not because we are required to. Because our customers deserve to know exactly what they are buying — and "trust us, it's tested" was never good enough.

We also encapsulate our NMN in-house. We source the raw NMN powder, control the fill process, and test the batch before it reaches you. When you buy our capsules, you are getting the same ingredient we put in our own supply chain — not a finished product we bought from a third party and relabelled.

What to Ask Any NMN Seller Before You Buy

Whether you buy from us or anyone else, ask these five questions before you hand over your money:

A legitimate, transparent NMN supplier should be able to answer every one of these questions without hesitation. If you get vague answers, redirects to marketing language, or claims that the water test proves purity — that tells you what you need to know.

💷 The Price Difference — What You're Actually Paying Per Capsule

Testing credentials matter. But so does price. Because if you are paying £2.00 per capsule for NMN when Eurofins-verified NMN is available at £0.48 per capsule — that is a question worth asking.

Here is what a month of 500mg NMN supplementation actually costs from each UK source, based on publicly listed prices at April 2025:

Prices based on publicly listed retail prices at April 2025. Promotional pricing, subscription discounts and multi-buy offers may vary. Always verify current pricing before purchase.

The price gap is worth stating plainly: you are paying up to £43 more per month at Boots for NMN where the testing lab is not named on the product listing. That is not a small premium for transparency — it is a very large premium for considerably less publicly stated transparency.

We are not saying our NMN is better because it is cheaper. We are saying it is Eurofins tested, 99.94% pure, Size 0, no fillers — and it costs £0.48 per capsule. Both things are true at the same time.

The Bottom Line

The UK NMN market in 2025 is a market where:

• The UK's largest supplement retailer no longer sells own-brand NMN — listing Charava as a third-party brand instead
• Multiple peer-reviewed studies have confirmed that a significant proportion of NMN products contain less NMN than stated — in some cases, effectively none
• The most common substitute is B3 Nicotinamide — which looks identical in a capsule and dissolves identically in water
• GMP certification and facility ISO standards, while legitimate credentials, do not independently verify the purity of a specific batch
• The taste test — which takes 10 seconds and requires no equipment — is the only at-home test that cannot be faked

We have been importing and supplying NMN since 2016. We test every batch with Eurofins. We encapsulate in-house. We use Size 0 capsules. Our COA is available on request. We have 149,000+ verified marketplace sales. We hold a 5 Star Food Hygiene Rating.

We are not the only supplier you should trust. But we are telling you exactly what to look for — so you can judge any supplier, including us, on the same standard.

Do the taste test. Check the capsule size. Ask for the COA. Ask who the lab is.

If the answer to any of those questions makes you uncomfortable — that discomfort is your answer.