Health Claims for Supplements in the UK: A Website Compliance Guide

Health claims for supplements in the UK must come from the GB Nutrition and Health Claims Register in Great Britain, worded closely and with conditions of use met. You can't say a supplement prevents, treats or cures disease, and the ASA applies these rules to your own website, social posts and marketing emails.

That sounds simple until you look at a real supplement website. Claims hide in product descriptions, FAQ answers, image overlays, customer reviews you've featured, meta descriptions and the subject lines of your promotional emails. This guide walks through the rules that apply, who enforces them, and a practical way to check every page and email before it goes live.

This is a practical summary, not legal advice. For new products or bold claims, check the register yourself and get specialist regulatory advice.

Who regulates supplement marketing in the UK

Food supplements are regulated as foods, not medicines. Several bodies have a hand in how you can market them:

Northern Ireland follows different rules for some food law, including the EU register of claims, so brands selling across the whole UK need to check both.

The GB Nutrition and Health Claims Register

The register, maintained by DHSC, sets out all authorised and rejected nutrition and health claims for Great Britain. GOV.UK puts it plainly: "Only authorised claims in the Great Britain NHC register may be used in Great Britain." It was last updated in May 2026, so check the current version rather than relying on an old download.

Each authorised claim has three parts you need to respect:

1. The nutrient or substance. For example, vitamin D, zinc, or EPA and DHA.
2. The claim wording. For example, a claim that a nutrient "contributes to the normal function of the immune system".
3. The conditions of use. Usually a minimum amount the product must provide, and sometimes information you must give the consumer.

What "close to the wording" means in practice

You don't have to copy claims word for word, but any rewording must keep the same meaning for consumers and must not strengthen it. A light edit that keeps the word "normal" and the specific body function is far safer than a punchy rewrite. Phrases such as "boosts your immunity" or "supercharges your defences" suggest more than a contribution to normal function, which is exactly the kind of exaggeration the ASA looks for. If in doubt, stay with the register wording.

General wellbeing claims

Phrases such as "for vitality", "feel your best" or "wellness support" refer to general health benefits without naming a specific function. Under the rules these general claims must be accompanied by a specific authorised health claim. On a product page, that means putting the authorised claim right next to the general statement, not three scrolls down.

Ingredients without authorised claims

Many popular botanicals and novel ingredients have no authorised health claim at all. You can describe the ingredient factually (what it is, how much is in each serving, where it comes from), but you can't imply a health benefit for it. In a May 2026 ruling against Birling Shore Ltd, the company behind a children's mushroom supplement, the ASA objected to phrases such as "brain support" that went beyond authorised wording, and to claims linked to ingredients such as Lion's Mane and saffron, which have no authorised claims.

The CAP Code on supplement websites

The ASA's remit covers marketing on your own website and social media accounts, not only paid adverts. Product pages, landing pages, blog posts that promote a product, and influencer posts you pay for or control are all in scope.

The rules that most often catch supplement sites:

• No disease claims. Claims that state or imply a food supplement can prevent, treat or cure human disease breach rule 15.6.2 of the CAP Code. This includes naming conditions in testimonials.
• Only authorised health claims. The ASA's advice on beauty supplements is clear that if a health claim isn't on the GB register, evidence for it doesn't help.
• No health professional endorsements. Supplements can't be marketed with endorsements from doctors or other health professionals. In the Birling Shore ruling, a "Meet the Experts" section with quotes from apparent doctors breached the Code, and a note saying some identities were AI-generated didn't fix it.
• Testimonials count as your claims. If you publish a review that says a product cleared someone's anxiety, you've made a medicinal claim. The ASA treated testimonials mentioning conditions such as ADHD and depression as medicinal claims in the same case.

Weight-control supplements

Slimming and weight-control products face extra scrutiny under the CAP Code's weight-control rules as well as Section 15. Before-and-after photos, "lose X pounds" promises and references to weight-loss medicines are high-risk. If you sell in this category, have your copy reviewed before launch.

When a supplement becomes a medicine: MHRA borderline products

The MHRA calls products that sit between foods, cosmetics and medicines "borderline products". Its guidance on how to tell if your product is a medicine says it looks at:

• the claims made about the product, both explicit and implied
• the pharmacological properties of the ingredients, including herbal ingredients
• the product's main intended purpose
• whether similar licensed products exist
• how it's presented through labelling, packaging, promotional literature and advertisements

Supplements containing familiar nutrients such as vitamins and minerals are usually regulated as foods. But a product presented as treating or preventing a condition can be classed as a medicine, which would need a licence. "Natural" or herbal ingredients don't exempt a product.

Your website is part of the presentation. A product page that says "relieves joint pain" or "helps with insomnia" can do as much damage as the label. If you're unsure, the MHRA offers a borderline advice route, and an opinion that a product isn't a medicine is not an approval to sell or advertise it.

Where health claims for supplements hide on UK websites

Most brands check the product description and stop there. These are the places we find claims drifting most often:

1. Meta titles and descriptions. Search snippets are marketing. "Cure your fatigue naturally" in a meta description is a disease-style claim in front of every searcher. Check them with the free meta tag checker.
2. Image text. Infographics, lifestyle banners and pack shots with benefit callouts. Search engines and the ASA can both read them.
3. FAQ answers. "Can this help with my IBS?" answered with anything other than a neutral, non-medical reply is a problem.
4. Featured reviews and UGC carousels. Moderate before you publish, and don't pin reviews that name conditions.
5. Structured data. The description in your Product schema should match the compliant on-page copy. Validate it with the schema markup validator.
6. Blog posts. An article about "foods that fight inflammation" that links straight to your turmeric capsules is product marketing.
7. Affiliate and influencer content. If you pay for it or control it, it's your ad.
8. Old pages. Retired products and archived campaign pages often carry pre-2021 claims. A broken link checker helps you find stray links to them.

Compliant marketing emails for supplement brands

Email is often the biggest revenue channel for supplement brands, thanks to repeat orders and subscriptions. Two sets of rules apply.

The claims rules apply to email too

Subject lines, preview text and banners are marketing communications. "Beat winter colds" in a subject line is a disease-prevention claim even if the email body is careful.

PECR and the soft opt-in

The ICO's guidance on electronic mail marketing says you must not send marketing emails to individuals without specific consent, with a limited exception for your own previous customers, known as the soft opt-in. It only applies when you collected the details during a sale or negotiation, the marketing is about your similar products, and you offered an opt-out at collection and in every message.

The stakes went up on 5 February 2026, when the Data (Use and Access) Act 2025 brought maximum PECR fines in line with UK GDPR. Our guide to cookie consent under the Data (Use and Access) Act covers the website side.

Make sure the emails actually arrive

Subscription reminders and order confirmations need SPF, DKIM and DMARC set up for your sending domain. Run the free email deliverability checker before a big promotion, and see Gmail, Yahoo and Microsoft's sender requirements if you send in volume.

A pre-launch checklist for supplement product pages

Use this for every new product and whenever you rewrite copy:

1. List every health-related statement on the page, including image text, FAQs, reviews and the meta description.
2. Match each one to an authorised claim on the current GB register. Note the register entry.
3. Confirm the product meets the conditions of use at the recommended daily dose.
4. Put any general wellbeing statement next to a specific authorised claim.
5. Remove disease words: treats, cures, prevents, heals, relieves, and named conditions.
6. Remove or rewrite any testimonial that mentions a condition or a result you can't claim.
7. Remove endorsements from doctors, pharmacists, nutritionists presented as health professionals, or anyone styled as one.
8. Check the Product schema description matches the visible copy.
9. Show doses, ingredients, allergens and warnings as real text, not only in label images.
10. Check marketing emails and social captions for the same product against the same list.

Keep a record of which register entry supports each claim. If the ASA receives a complaint, you'll need to show it quickly.

The technical side: fast, trustworthy product pages

Compliance protects you from complaints. Speed and trust signals win the sale. Supplement pages tend to be heavy with bottle shots, capsule close-ups and lifestyle images. Compress them with the free image compressor and keep the main product image small, because it's usually the Largest Contentful Paint element. Our guide to improving Largest Contentful Paint explains why.

Certificates of analysis and specification sheets build trust when buyers can open them quickly on a phone. A PDF compressor shrinks scanned certificates without changing your originals.

You'll find the full set of free tools we recommend for this sector, from image optimisation to DMARC checks, on our free tools for health and supplement brands page.

FAQ

What health claims can I make for supplements in the UK?

In Great Britain you can only use health claims listed as authorised on the GB Nutrition and Health Claims Register, and your product must meet each claim's conditions of use. You can adapt the wording slightly as long as the meaning stays the same and isn't strengthened. Claims that a supplement prevents, treats or cures disease are not allowed.

Does the CAP Code apply to my supplement website?

Yes. The ASA's remit covers marketing claims on your own website and on social media accounts you control, not just paid adverts. Product descriptions, landing pages, promotional blog posts, featured testimonials and influencer content you pay for or direct are all in scope, so they all need the same claims check.

Can I use customer reviews that mention health conditions?

Not as marketing. If you publish or feature a review saying a supplement helped with a named condition, the ASA treats it as your own medicinal claim. Moderate reviews before they appear on product pages, don't pin or quote ones that mention conditions, and avoid using them in emails or ads.

When could the MHRA treat my supplement as a medicine?

The MHRA looks at claims, ingredients, intended purpose and presentation, including your website and adverts. If a product is presented as treating or preventing a condition, or works through a significant pharmacological action, it may be classed as a medicine that needs a licence. Herbal or natural ingredients don't change this.

Can a nutritionist or doctor endorse my supplement online?

The CAP Code doesn't allow food supplements to be marketed with endorsements from health professionals. In a 2026 ruling the ASA found a "Meet the Experts" section with apparent doctors in breach, even with a disclaimer that some identities were AI-generated. Factual, non-promotional educational content is a different matter, but get advice first.

Do marketing emails for supplements need consent?

Usually. Under PECR you need specific consent to send marketing emails to individuals, unless the soft opt-in applies to your own customers who bought from you, were offered an opt-out and receive marketing about similar products. The health claims rules apply to subject lines and email content too.