Supplement Health Claims: UK Advertising Rules (2026)
15 mins
26.06.26
Supplement Advertising in the UK: What Health Claims You Can and Can’t Make
Here is the short version. In the UK you can only make a health claim about a supplement if that claim is authorised on the GB Nutrition and Health Claims Register. You can never say or imply a supplement treats, prevents or cures a disease. And vague wellbeing language, the “supports your wellbeing” and “detox” type of copy that fills most supplement feeds, is only allowed if you pair it with a specific authorised claim right next to it.
The catch in 2026 is that the ASA now uses AI to find breaches before anyone complains, and supplements are one of its priority targets. This guide explains how the register works, the claims that quietly break the rules, and how to market a supplement hard while staying inside the lines.
Why supplement brands are getting caught more than ever
The rules are not new, but the detection is. The ASA runs an AI-based Active Ad Monitoring System that proactively scans online ads, which means your content can be investigated even when no member of the public has complained. A large share of recent supplement rulings came from that system, not from complaints.
The enforcement has come in clear waves. There was a run of rulings against products claiming to help with stress, anxiety, low energy and “brain fog”. There was a separate set against sleep claims, where the ASA pointed out there are no authorised health claims about sleep quality on the GB register at all. And in August 2025 there were rulings against supplements positioning themselves as alternatives to weight-loss drugs. The pattern is consistent: wellness language that sounds harmless, assessed against a register that is far narrower than most brands assume.
The one rule everything hangs on: the GB register
A food supplement is legally a food, not a medicine, so it falls under Section 15 of the CAP Code and the retained nutrition and health claims regulation. Since 1 January 2021, only health and nutrition claims authorised on the Great Britain Nutrition and Health Claims Register, or claims with the same meaning to a consumer, may be used in marketing. The register, maintained by the Department of Health and Social Care, lists every claim that has been assessed and approved for use in Great Britain.
Two consequences follow that brands routinely miss. First, if a claim is not on the register, you cannot make it, and you cannot use a reworded version that means the same thing. Second, if your product does not contain an ingredient that has an authorised claim, your ad should contain no health claims at all. Northern Ireland follows a different set of rules, so campaigns running there need separate legal advice.
The line you can never cross: medicinal claims
Unless your product is a licensed medicine, you cannot make a medicinal claim, directly or by implication. A medicinal claim is any claim that a product can diagnose, treat, prevent or cure a disease, injury or adverse condition, whether physical or mental. This is an absolute prohibition, not a grey area.
There is one narrow exception: “reduction of disease risk” claims are permitted, but only if that specific claim is authorised on the GB register and presented clearly without exaggeration. Everything else in the disease space is off limits. A particularly common trap in 2025 was comparing a supplement to a prescription weight-loss medicine, for example a product marketed as preserving muscle better than Ozempic. The ASA treated that as making the supplement medicinal by presentation and ruled against it. The same prescription-only medicine rules covered in our weight-loss marketing guide apply here in reverse: you cannot borrow a drug’s reputation to sell a supplement.
Specific versus general health claims: the distinction brands get wrong
This is where most compliant-looking ads fall down. The rules split health claims into two types.
Specific health claims (SHCs) describe a relationship between a particular nutrient and health, for example that vitamin C contributes to the normal function of the immune system. These are allowed only when the exact claim, or one with the same meaning, is authorised on the GB register, the product contains a qualifying amount of that nutrient, and the conditions of use are met.
General health claims (GHCs) are vague, non-specific benefit statements such as “good for you”, “healthy”, “detox”, “refuel your brain” or “unlock a stronger body and mind”. A general claim is only permitted if it is accompanied by a relevant authorised specific claim, placed next to or immediately after it. A general claim on its own is a breach, and the ASA has ruled on exactly these phrasings.
One more technical rule catches careful brands out. An authorised claim must be attached to the nutrient it was approved for, not to your product as a whole. You cannot take an authorised claim about, say, zinc and rewrite it so the benefit is attributed to your brand name instead of to zinc. Claims are also judged on how a consumer is likely to interpret them, not on what you intended, so implied claims count just as much as explicit ones.
The wellness vocabulary that quietly breaks the rules
Some of the most common words in supplement marketing are themselves treated as health claims, which means they need authorisation or appropriate pairing.
“Detox” is treated as a general health claim, so it needs an accompanying authorised specific claim.
“Adaptogen”, “nootropic” and “antioxidant” have been treated as specific health claims, which means they need to map to an authorised claim on the register.
Stress, anxiety, mood, focus, energy and “brain fog” claims have all been ruled against where they were not authorised or strayed into medicinal territory.
Sleep claims such as “deeper sleep” or “a better night’s sleep” are high risk, because there are no authorised sleep-quality claims on the GB register to support them.
“Immunity” language is only safe when it sits on an authorised nutrient claim, for example vitamin C or vitamin D and normal immune function, used correctly.
Weight-loss supplements: a category of its own
Weight-loss supplements carry extra rules under the weight control provisions. You cannot refer to a rate or amount of weight loss for a food or supplement. Claims like “lose 15 to 20 percent of body weight”, or a testimonial saying “I’ve lost 8kg”, have both been ruled against because they attach an amount of weight loss to a food product.
On top of that, as covered above, you cannot present a supplement as equivalent to or better than a prescription weight-loss medicine, and you must not target under-18s. If weight management is your category, treat it as the highest-risk corner of an already strict area.
CBD and novel ingredients
CBD deserves its own warning. There are currently no authorised health claims for CBD on the register, which means you cannot make any health claim about CBD itself. Stick to factual descriptions such as the fact that a product contains hemp-derived CBD, reference quality standards or third-party testing, and lean on non-health features like flavour or format. If your product also contains vitamins or minerals that do have authorised claims, you may use those claims, but only attributed to those nutrients, never to the CBD. CBD also sits within the novel foods regime, and the ASA has ruled against brands implying medical efficacy, including through influencer content. As with all supplements, keep marketing away from under-18s.
Testimonials, influencers and user content carry the same liability
You are responsible for the claims in any testimonial, influencer post or piece of user-generated content you use or incentivise. The ASA has ruled against ads where customer testimonials said things like “my pain disappeared” or that a product reduced their anxiety, treating them as prohibited medicinal claims, and against testimonials that referenced an amount of weight lost.
The same applies to affiliate and influencer activity. A claim you could not make yourself does not become acceptable because a creator or a customer made it. Disclosure is also required, so paid or gifted content must be clearly labelled. The safe approach is to pre-approve all creator copy, screen user content before you amplify it, and write the claims rules into your creator contracts.
What you absolutely can do: the compliant playbook
None of this means a supplement brand has to market with one hand tied. It means being deliberate about where claims come from.
Use authorised specific health claims properly: the right nutrient, wording that matches the approved meaning, a qualifying amount in the product, and the conditions of use met.
Pair any general wellbeing language with a relevant authorised specific claim placed immediately alongside it.
Lead with everything that is not a health claim: taste, texture, format, sourcing, third-party testing, sustainability, vegan or organic credentials where true, convenience, price and brand story. Plenty of strong supplement brands sell mostly on these.
Hold your evidence: documentation that the claim is on the register and that your product meets its conditions of use.
Screen testimonials, influencer copy and user content before it goes live, and bake compliance into creator contracts.
Get separate legal advice for any campaign running in Northern Ireland, where a different register applies.
This is exactly the kind of judgement a specialist healthcare social and content partner brings: knowing which claims are safe, how to phrase them, and how to build a feed that sells without triggering a ruling.
Quick compliance checklist to action today
Check every health claim against the GB Nutrition and Health Claims Register.
Remove any claim that a product treats, prevents or cures a disease, including implied and mental-health versions.
Make sure every general wellbeing phrase is paired with an adjacent authorised specific claim.
Attach each authorised claim to the correct nutrient, not to the product or brand name.
Review buzzwords: detox, adaptogen, nootropic, antioxidant, immunity, sleep, stress and focus.
Remove any rate or amount of weight loss and any comparison to weight-loss medicines.
Make no health claims about CBD itself, and keep all supplements away from under-18 audiences.
Screen and pre-approve all testimonials, influencer and user content, and label ads clearly.
Frequently asked questions
Can I say my supplement supports wellbeing or is good for you?
Only if you pair that general phrase with a specific authorised health claim placed immediately next to it. A vague wellbeing claim on its own breaches the rules.
Can a supplement claim to treat anxiety, pain or poor sleep?
No. Claims to treat, prevent or cure a physical or mental condition are medicinal claims and are prohibited for supplements. There are also no authorised sleep-quality claims on the GB register to support sleep claims.
How do I know if a health claim is allowed?
Check the GB Nutrition and Health Claims Register. If the claim, or one with the same meaning, is not listed, you cannot use it, and your product must contain a qualifying amount of the relevant nutrient and meet the conditions of use.
Are influencer and customer testimonials covered by these rules?
Yes. You are responsible for the claims in any testimonial or influencer post you use or incentivise. A claim you could not make yourself does not become acceptable because someone else made it.
Can I market my supplement as a natural alternative to Ozempic or a weight-loss jab?
No. Comparing a supplement to a prescription weight-loss medicine makes it medicinal by presentation and breaches the rules, and you also cannot refer to a rate or amount of weight loss.
Can I make health claims about CBD?
No. There are currently no authorised health claims for CBD, so you cannot make health claims about the CBD itself. Stick to factual descriptions and non-health features.
Market your supplement brand without earning a ruling
Otta builds compliant, high-performing social and content for healthcare and wellness brands, so the line between a strong claim and a banned one is handled before anything goes live. If you want a supplement brand that grows fast and stays clean with the ASA, get in touch and we will show you what compliant, commercial marketing looks like in this category.
This article is general guidance, not legal advice. The health claims framework is complex and continues to develop, so always check the current GB Nutrition and Health Claims Register, DHSC guidance and the CAP Code before publishing.
Sources and further reading
ASA / CAP, food: health claims
ASA / CAP, supplementary advice on health claims in ads for supplements
