Note: This advice is given by the CAP Executive about non-broadcast advertising. It does not constitute legal advice. It does not bind CAP, CAP advisory panels or the Advertising Standards Authority.

BREXIT - The CAP and BCAP Codes include many rules which seek to reflect significant pieces of EU law or UK law that has been made to implement EU law. As far as CAP is aware, the same rules and laws will apply on the day after exit as on the day before. This CAP News Article explains the position further.

CAP is aware of unlicensed slimming pills, herbal remedies and patches that purport to aid weight loss. Neither CAP nor the ASA has seen convincing evidence that such unlicensed products can alone result in weight loss (Meridian Leisure South Ltd, 26 May 2004; New Lifestyle Company Ltd, 17 March 2004, and Pro-Medicus, 26 March 2003).

“Slimming” patches

Patches may be advertised on an availability-onlyplatform or may be advertised as being a prompt to remind wearers to stick to their diets. No efficacy claims should be made (Advanced Health & Beauty Ltd, January 2000).


Marketers should bear in mind that any ingested products that claim to have an effect on metabolism may be medicinal and therefore prohibited by rule 12.11, unless licensed by the Medicines and Healthcare products Regulatory Agency (MHRA). Claims such as “decrease appetite”, “burn fat” and “speed up metabolism” are likely to be medicinal and should not be made for unauthorised products (HealthiChoice, 8 September 2004). Marketers for slimming products that make such claims should first consult the MHRA to ensure their claims do not breach the medicines regulations.

Fat binders

While some marketers refer to fat binders as “supplements”, if the product is classed as a medical device, it will not also be considered a food, for the purpose of the CAP Code. Therefore, marketers should ensure that they hold rigorous product specific scientific data, which proves that a medical device which acts as fat binder can work as described (rule 12.1). See Weight control: Fat binders and Weight control: chitosan.

If the product is not classed as a medical device, the product is likely to be a food supplement and therefore the Food Rules (section 15) will apply in addition to any relevant Weight Control and Slimming rules (section 13). Please read our guidance on Weight control: Food and Food supplements.

In 2007, the Copy Advice team was asked to review evidence for a pill that supposedly blocked starch from being absorbed by the body. Although it was considered plausible by CAP’s independent expert, the evidence was rejected because the product was considered a ‘breakthrough’ and should be supported by more than just one robust study.

Medicines, Medical devices and Traditional Herbal Remedies

For products that have been authorised by the MHRA, advertised claims should not exceed those specified in the marketing authorisation. The ASA has previously upheld complaints against Newtons Traditional Remedies Ltd, despite the MHRA authorisation of the product. By asserting that the product gave rise to “visible, seeable results” and “fat reduced within a couple of weeks with excess inches just falling away” the marketer went further than the authorisation allowed. The product product was a herbal remedy traditionally used as an aid to [short-term] slimming. Newtons’ problems didn’t stop there. The ASA also upheld a challenge against the marketer for irresponsibly suggesting that consumers should want to lose weight for special occasions such as “parties, clubbing, dates, holidays etc.” (Newtons Traditional Remedies Ltd, November 2000 and September 1999).

Marketers should neither state or imply they are offering medicines if they are not (Foxglove Clinic, 25 February 2004) nor imply products have been clinically tested or medically approved if they have not (Goldshield Pharmaceuticals Ltd, 3 November 2004, and New Lifestyle Company Ltd, 17 March 2004).

Prescription-only medicines (POMs)

Marketers should note that prescription-only medicines (POMs) should not be advertised to the public. See Weight control: Prescription only medicines.


Obesity is frequently associated with medical conditions and rules 12.2 and 13.2 state that marketers should not offer specific advice on, diagnosis of or treatment for it unless it is conducted under the supervision of a medical doctor or other suitably qualified health professional. See Weight Control: Obesity.

See other associated entries on "Weight control"

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