Third-party tested supplements: what that actually means in the UK

Third-party tested appears on a great many supplement packs and on rather more websites. It reads as though a standard has been met. It is not a standard. It is a sentence, and nothing stops anyone from typing it.

The useful version of the phrase is longer and duller. Which laboratory did the testing. What that laboratory is accredited to do. What it tested for. Which batch it tested. Answer those four and you have learned something about a product. Leave them unanswered and the words on the pack are decoration.

What does third-party tested actually mean?

At its narrowest the term means only this: the testing was not done by the party selling the product, and not by the party buying it. A first party is the manufacturer. A second party is the customer or the retailer. A third party is somebody with no commercial interest in the answer. That is the entire content of the phrase. It says a sample went somewhere else.

Why the phrase has no legal meaning

There is no definition of the phrase in food law, no register of firms entitled to use it and no authority that polices it. It is marketing language that has borrowed the cadence of a technical term. A brand can send one batch to one laboratory once, receive one report, and print the words on every pack it makes for the next five years without breaking any rule. Nothing about the sentence is time-limited, and nothing about it is tied to the tablets in your hand.

The same goes for the phrases that travel with it. Lab tested, purity verified, quality assured, independently tested and rigorously tested are all outside the rules in the same way. They differ in tone, not in status. Read them as a claim that something happened, then ask what.

Four questions turn the phrase into information:

• Which laboratory? A name, not an adjective. An in-house laboratory owned by the manufacturer is not a third party, whatever the report looks like.
• Accredited to do what? Accreditation is granted for a defined list of tests. The list matters more than the word.
• Tested for what? Identity is a different test from heavy metals, which is a different test again from microbiology. A product tested for one has not been tested for the others.
• Which batch? A result belongs to the run of product the sample came from. It does not belong to the brand.

None of those questions is hard to answer, and a company that has done the work can answer all four in a sentence each. That is the real function of the phrase. Not evidence, but a prompt.

What does ISO/IEC 17025 accreditation cover?

ISO/IEC 17025 is the standard behind almost every honest use of the phrase. Its full title is General requirements for the competence of testing and calibration laboratories, and the current edition was published in 2017. The word to notice is competence, and the thing whose competence is being judged is a laboratory. The standard says nothing about supplements. It contains no pass mark for a product, because products are not what it looks at.

In the United Kingdom the body that grants this accreditation is UKAS, the United Kingdom Accreditation Service. UKAS was appointed as the national accreditation body by the Accreditation Regulations 2009, and it is the only one the country has. It assesses a laboratory's people, methods, equipment, records and results, then issues a certificate and a schedule of accreditation.

Why the schedule matters more than the word

Accreditation is also narrower than it looks. The schedule is the part that matters. It lists the specific tests a laboratory may carry out under accreditation, the method used for each one, and the materials each may be applied to. Anything absent from the schedule is outside the accredited scope, even where the same laboratory performs it. A laboratory accredited for heavy metals in drinking water has not thereby been judged competent to measure heavy metals in a milled root. This is why a brand that names its laboratory is telling you more than a brand that names a standard.

Schedules are published. UKAS keeps a public directory of accredited organisations, each with an accreditation number, and each schedule can be downloaded and read. UKAS certificates carry no expiry date, because a current schedule sitting on the register is what shows the accreditation is live. Checking a laboratory this way takes a few minutes and almost nobody does it. Where a laboratory sits outside the UK, its results still carry weight through the International Laboratory Accreditation Cooperation arrangement, under which signatory accreditation bodies accept one another's accredited results.

Our own position needs stating plainly, because this is the line most brands blur. AllMaleUp batches are tested at a laboratory accredited to ISO/IEC 17025. The accreditation belongs to that laboratory. It does not belong to us, it does not transfer to us because we pay the invoice, and it is not an approval of the tablets. AllMaleUp holds no accreditation and no certification from any body. It is a food supplement sold under food law, like every other food supplement on the shelf. That separation is not a technicality. It is the only reason the result is worth anything: the laboratory is judged by somebody who is not us.

Does any UK authority certify or approve a supplement?

GMP stands for Good Manufacturing Practice, and it is the second phrase in this aisle carrying more weight than it should. In British regulation the term has a precise home. Government guidance defines good manufacturing practice as the minimum standard that a medicines manufacturer must meet in their production processes. GMP certificates are issued by the Medicines and Healthcare products Regulatory Agency, after inspection, to the holders of medicines manufacturing licences.

A food supplement factory is not in that system, because a food supplement is not a medicine. No United Kingdom authority issues a GMP certificate for a supplement line. When a supplement site describes itself as GMP-registered, it means one of two things: it runs production to good manufacturing practice as an internal standard, or it has paid a private audit scheme to inspect the site and say so. Neither is dishonest. Neither is a government approval. Both describe a building and the way work is organised inside it, and neither says anything about the contents of a particular carton.

What the law actually asks of a supplement factory is less glamorous. Food supplements are food, so the general hygiene rules apply. Assimilated Regulation (EC) 852/2004 requires that food business operators put in place, implement and maintain a permanent procedure or procedures based on the HACCP principles - Hazard Analysis and Critical Control Points, a method for identifying the points in a process where things can go wrong and controlling them. The business must also register with its local authority at least 28 days before it starts trading. Registration is free and cannot be refused. It records that a business exists. It is not an inspection, an assessment or an endorsement.

The consequence is the most useful fact in this article. Nobody in Britain approves an individual food supplement before it is sold. The Department of Health and Social Care says in its own guidance that it does not authorise or check the composition or labelling of individual products, and the UK decided not to require prior notification of supplements either. Enforcement comes afterwards and locally, through trading standards and environmental health officers at your council. A pack implying government approval is therefore describing something that does not exist. That includes ours. AllMaleUp is pressed in the UK on a GMP-registered line, which is a fact about a factory, not a certificate from anyone.

Informed Sport, NSF, and who sports certification is for

There is one kind of certification that does attach to a product rather than a place, and it is worth knowing who it is for. Informed Sport, run by the laboratory business LGC and set up in 2008 with UK Anti-Doping, tests every batch of a certified product before it is released and screens for more than 285 substances prohibited in sport. NSF Certified for Sport is the American equivalent, recognised by a list of United States sporting bodies. Both exist for one group of people: competitors under anti-doping rules, where a positive test is the athlete's responsibility however the substance arrived. If you are liable to be tested, those marks are the ones to look for. If you are not, they answer a question you were not asking. Neither is a verdict on whether a product is any good, and Informed Sport states plainly that no supplement testing programme can test for every substance on an open-ended prohibited list.

How do you read a Certificate of Analysis?

A Certificate of Analysis, usually shortened to CoA, is the document all of this ends in. It is a laboratory report on a defined quantity of material. A header identifies the product, the batch or lot and the date of analysis. Below it sits a table of tests, and each row should carry four things: what was measured, by what method, what the result was, and what limit the result was measured against. A result with no limit beside it is a number without a verdict.

The first check is the least technical one. The batch code printed on the side of the carton should match the batch reference on the certificate. If it does not, you are reading a document about somebody else's tablets. A generic certificate, a specimen certificate, or a certificate with the batch field left blank is a marketing PDF wearing a laboratory's clothes.

After that, read in this order. Whose name is at the top, and is it the manufacturer's own laboratory or an outside one. Whether an accreditation number is given. Whether the method is named for each test. Whether the date of analysis falls after the date the batch was made. Whether limits are printed beside results. One phrase is worth understanding before you meet it: not detected does not mean absent. It means not found at the limit of detection of the method used, which is a smaller and more careful statement.

For a botanical tablet the panel is usually identity, heavy metals, microbiology and the physical specification. Identity confirms each plant is the species declared. Heavy metals covers lead, cadmium, mercury and arsenic. Microbiology covers total counts and specific organisms. The physical specification confirms weight and moisture. Ours cover that ground, and we will send you the certificate for your own batch if you email the code to hello@maleup.co.uk. Retention samples from every run are kept, so a batch can be tested again if a question comes up later.

What a certificate of analysis cannot tell you

Here is the honest part, and it is the part most brands leave out. A certificate proves what was in one batch, on one day, by one method, within the uncertainty of that method. It proves nothing about the next batch. Plant material varies with season, soil, supplier and drying, which is exactly why testing is done per batch rather than once. A brand that tested in 2024 and has been quoting that report ever since has not been testing. It has been advertising.

What the pack says	What it guarantees	What it does not
Third-party tested	A sample went to an outside laboratory at some point	Which laboratory, which tests, or that your batch was one of them
Tested at an ISO/IEC 17025 accredited laboratory	That laboratory has been judged competent for the tests on its schedule	Anything about the brand or the product, or tests outside that schedule
GMP-registered site	A description of how a factory is organised	A certificate from a UK authority - GMP certificates go to medicines manufacturers
Registered food business	The local council knows the business exists	That anyone has approved, assessed or inspected the product
Certified for sport	That batch was screened for substances prohibited in sport	Quality, purity in general, or any statement about effect
Certificate of Analysis available	Results exist for some batch	That they are for the batch you were sold, unless the code matches

Six things are worth checking before you order, and every one of them can be done from a phone:

• Ask which laboratory does the testing, by name.
• Look that laboratory up on the UKAS register and open its schedule, to see whether the tests being claimed are on it.
• Ask for the certificate covering the batch code you will actually receive, not a specimen.
• Check that limits are printed beside results, and that methods are named.
• Check that the date of analysis is recent and falls after the manufacturing date.
• Ask what happens if you request a certificate after buying, and whether retention samples are kept.

None of this tells you whether a supplement is worth taking. It cannot, and no certificate ever will. What the paperwork tells you is whether a brand can account for what it sold you - who tested it, against what, and when. That is a lower bar than it sounds, and a good deal of the aisle does not clear it.

Common questions

† Describes the traditional use of these botanicals (UK 'on-hold' botanical claims under retained Regulation (EC) 1924/2006). Not authorised EFSA health claims. AllMaleUp is a food supplement, not a medicine.