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.
The ASA and CAP receive many enquiries about marketing communications for slimming or weight control products. They include the conventional (calorie-controlled diets), the helpful (exercise regimes), the purely cosmetic (the girdle) and the ridiculous (slim-while-you-sleep-type pills and weight loss insoles). This AdviceOnline entry summarises the Code’s requirements; we advise marketers to read the associated entries on “Weight control" linked below.
Prescription-only medicines (POMs)
Referring to precise amounts of weight loss / weight loss from specific areas
Marketers must not give the impression that dieters cannot fail
Testimonials and before and after photos
Food, soft drinks and supplements
Prescription-only medicines (POMs)
Prescription-only medicines (POMs) cannot be advertised to the public (rule 12.12)
Following an influx of complaints about ads for POM treatments for weight-loss in 2020, CAP issued an enforcement notice against marketers advertising the medicine to the public.
See Weight control: Prescription-only medicines
Substantiation
The main self-treatment for achieving weight loss is a slimming regime in which the intake of energy (calories) is lower than the output. Any claim made for the effectiveness of a slimming method or product should be backed by rigorous practical trials conducted on people; testimonials that are not supported by trials do not constitute adequate substantiation (Shop TJC Ltd, 21 June 2023 and Bio-Medical Research Ltd, 10 March 2021). See Rule 13.1 and the CAP guidance on the level of substantiation expected in health, beauty and slimming claims.
Combining a diet with an unproven weight reduction method does not justify making claims about that method (Rule 13.4).
Obesity
Overweight is characterised in adults by a Body Mass Index (BMI) of 25-29 kg/m2 and obesity is defined by a Body Mass Index (BMI) of more than 30 kg/m2. Previously, it was unacceptable for advertisers to refer to obesity in marketing unless their services were supervised by a suitably qualified healthcare professional (Rule 13.2). Following a rule change in November 2015 there is now an exception to rule 13.2 which means it is now possible for services meeting specific criteria laid out in rule 13.2.1 to refer to obesity and therefore target the obese if they offer lifestyle weight loss programmes which meet specific criteria.
Weight reduction achieved through loss of water alone does not constitute a treatment for the overweight or for those who are obese.
See Weight control: Obesity and lifestyle weight management programmes
Exploiting the vulnerable
Marketers should not exploit the vulnerable, suggest that it is desirable to be underweight or target those for whom weight reduction is likely to result in a potentially harmful body weight (a BMI of less than 18.5 kg/m2). (JA Physique Ltd 27 July 2022 and Egemed Hastaneleri 10 May 2023)
Marketing communications for slimming aids or weight reduction regimens should neither target nor appeal to consumers under the age of 18 (Rule 13.3). McDonald's Restaurants Ltd, 14 August 2019)
Referring to precise amounts of weight loss / weight loss from specific areas
Claims that one could potentially lose a precise amount of weight within a stated period of time (with the exception of marketing communications for surgical clinics, 13.9) or from specific parts of the body should be avoided (The Clean Supps LLC, Happy Koala LLC, 3 July 2024, and L(A)B Life and Beauty 16 December 2020)
If proven, and in line with good medical and nutritional practice, marketers are likely to be able to claim that certain individuals have lost exact amounts of weight in a given period. However, health claims that refer to a rate or amount of weight loss are not permitted in relation to food or food supplements, Rule 13.10.1 and 15.6.6). It is unacceptable to advertise that those who are overweight (but not obese) have lost more than 2lbs a week (Rule 13.10).
Marketers must not give the impression that dieters cannot fail
Marketers should not state or imply that dieters cannot fail to lose weight (rule 13.8) or that weight loss is permanent, because the amount of weight loss that can be achieved by individuals depends on many factors and cannot be guaranteed. Examples of unacceptable claims include: “You will lose several lbs in just a few weeks!” “guaranteed easy weight loss”, “you won’t put an ounce back on”, “the yo-yo effect is permanently avoided”.
Garments
Referring to short-term loss of girth resulting from a tight-fitting garment is likely to be acceptable as long as marketers do not imply that inch loss is permanent, or confuse short-term inch loss with weight loss or fat loss (Rule 13.12), (Person(s) unknown, 10 August 2022)). See Weight control: Garments.
Testimonials and before and after photos
CAP and the ASA regard the use of before and after photographs in the same way as testimonials. Marketers should ensure that they meet the requirements of rules 3.45 to 3.48 of the CAP Code. They should hold signed and dated proof that the photos are genuine. However, robust evidence should still be held to prove claims that consumers are likely to regard as objective (Pure Clear Minds Ltd, 10 May 2023). See Weight control: Testimonials and Before and after photos.
Food, soft drinks and supplements
Marketers promoting a food (or a soft drink) or food supplements in relation to weight should take the Food Rules into account and note that weight loss and other claims of this nature, which directly result in an effect on one’s health, are likely to be considered health claims for the purposes of Section 15 of the Code. A health claim for a food should not be made unless that claim is compatible with an authorised claim listed on the EU Register of nutrition and health claims (Not Guilty Food Co Ltd , 3 April 2024)
Marketers may offer dietary supplements as a safeguard against any shortfall in recommended intake when dieting, as long as they do not attribute weight loss to vitamins and minerals (Rule 13.6). The ASA ruled that referring to weight control in the category headings on a website would be understood as a claim about the function of the products listed in that category and that it was a health claim that should not be used unless authorised. (HOLLAND & BARRETT RETAIL LIMITED, 4 December 2019).
See Weight control: Food and Food Supplements and Weight control: Fat binders.
Alcoholic drinks
Health, fitness and weight control claims are not permitted for alcoholic drinks. The only permitted nutrition claims that could be made in relation to alcohol are “low-alcohol”, “reduced alcohol” and “reduced energy”. The ASA ruled that the claim “only 63 calories” was a nutrition claim equivalent to a low calorie/energy nutrition claim, which was not permitted in relation to alcoholic drinks (Wild Drinks Group Ltd 29 June 2022). In a similar case, it ruled that consumers would understand “skinny rebel” to mean that the advertised product could help maintain or lose weight. (Rebel Wine Ltd, 23 August 2023)
See Alcohol: Health, diet and nutritional claims and Alcohol: Low alcohol drinks
See Weight control: Food and Food supplements, Weight control: Pills, medicines and patches, Weight control: Calorie-controlled diets, Weight control: Testimonials, Weight control: Cellulite, Weight control: Exercise, Weight control: Complementary therapies, Weight control: Medical procedures
See also Medicinal Claims, Claims in names