Supplement marketing sounds like the Wild West. It is actually one of the more tightly regulated corners of UK advertising — the rules are just widely ignored.
Once you know them, marketing copy becomes a useful signal about the company behind it.
This is part of our series on how to choose a supplement.
There is an official list
The GB Nutrition and Health Claims Register sets out every health claim that may lawfully be made about a food or supplement in Great Britain. Each entry specifies the nutrient, the permitted wording, and the conditions of use.
Two consequences follow.
The wording is fixed. This is why compliant labels read so stiffly — "vitamin C contributes to the normal function of the immune system" rather than "boosts your immune system". The stilted phrasing is the lawful one.
There are conditions. A claim can only be used where the product contains a meaningful amount — generally at least 15% of the NRV per serving. Some claims carry further conditions: the omega-3 heart claim requires 250mg of EPA and DHA daily, the glucomannan cholesterol claim requires 4g daily.
A well-run label states those conditions. If a product claims the omega-3 heart benefit but you would need six capsules a day to reach the threshold, that should be disclosed.
Botanicals: named, not claimed
This is the biggest grey area, and worth understanding.
Thousands of botanical claims were submitted for assessment years ago and placed "on hold" pending evaluation that has never concluded. They are not approved. They are not formally rejected. They sit in limbo.
In practice, a cautious UK seller will name a botanical, describe it, and say what form and dose it is in — but will not tell you what it does.
So if you see confident, specific claims about ashwagandha, turmeric, milk thistle or valerian, you are looking at a company operating outside the rules. That may not bother you. But it is reasonable to ask what else they are relaxed about — dosing, sourcing, allergen declaration.
The line supplements cannot cross
Beyond nutrition claims sits a firmer boundary: a food supplement may not be presented as a medicine.
Under UK medicines law, a product can be classified as a medicine either by its ingredients or by its presentation — meaning how it is described and sold. Claim to treat, cure, prevent or relieve a disease, and you have arguably made your supplement an unlicensed medicine, regardless of what is in it.
Words that raise this issue: treat, treatment, cure, remedy, relief, heal, prevent — and naming a medical condition in a product title.
The regulators here are the MHRA for medicines classification and the Advertising Standards Authority for marketing. The ASA covers websites, social media and influencer posts — not just paid advertising.
I will be candid: this is an area where a lot of established sellers, including us at points, have carried wording that would not survive scrutiny. It tends to accumulate over years of copywriting rather than arriving through bad intent. That does not make it acceptable, and it is worth auditing periodically.
Claims that are always a warning sign
- Naming a condition — "for arthritis", "treats candida", "UTI relief"
- Cure or treatment language in any form
- Miracle framing — "what doctors will not tell you", "one weird trick"
- Before-and-after photos, particularly for weight products
- Testimonials making medical claims — the rules apply to customer quotes too
- Guaranteed outcomes — "lose 10lb in 2 weeks"
- Detox and cleanse language implying removal of unspecified toxins
- Immune "boosting" — the authorised wording is "contributes to normal function", and the distinction is real
Reading it as a buyer
You do not need to memorise the register. A simpler heuristic works:
Compliant copy is specific and modest. It names nutrients, gives quantities, uses careful phrasing and tells you what it cannot promise.
Non-compliant copy is vague and confident. It promises outcomes, names conditions, and rarely tells you how much of anything you are getting.
The irony is that the compliant version is more useful. "Contributes to the reduction of tiredness and fatigue" is a smaller promise than "banish fatigue for good" — but it is a promise backed by an assessed body of evidence and a specified dose. The other is backed by nothing at all.
Always read the label. Food supplements are not a substitute for a varied and balanced diet and a healthy lifestyle. If you have a medical condition or take medication, speak to your GP or pharmacist rather than relying on supplement marketing.
Explore more in our best sellers.
0 comments