Weight-loss and detoxing: Cut out the bad stuff and ensure a balanced diet of responsibility and evidence

Hot on the heels of Christmas festivities, comes the New Year and renewed commitments to a moderate lifestyle. Marketers keen to promote weight-loss products and regimes should take care to ensure they don’t tip the scales in favour of misleading advertising. With that in mind, here’s some advice to help you make sure that you don't bite off more than you can chew with your advertising of diets and weight-loss plans.

NOTE: This article does not relate to ads claiming food or food supplements can aid weight-loss, which are covered by the food rules.  For more on that topic, see our article here.

Hold evidence

Efficacy claims for any weight-reduction method or product must be supported by robust evidence. Beware of unsupported efficacy claims in product names too and remember testimonials alone aren’t sufficient to support efficacy claims.

Be realistic

Don’t exaggerate how much weight people are likely to lose, claim they can lose precise amounts of weight within a stated period, or from specific parts of the body, or that weight-loss will be permanent.

Be responsible

Don’t state or imply people can lose an irresponsible amount of weight or fat; for those overweight, but not obese, a rate of weight loss greater than 2 lbs a week is unlikely to be compatible with good medical and nutritional practice and should be avoided.


Don’t refer to obesity, or imply you treat those with the condition by featuring people who appear to be obese, unless you offer a multi-component lifestyle weight management programme, which meets all of the requirements set out in rule 13.2.1.

Before & after images

Got amazing pictures demonstrating your customers’ weight-loss? These too could be considered implied efficacy claims, so make sure you don’t exaggerate how much weight people are likely to lose, or indirectly promote an irresponsible amount or rate of loss.

Think you can cure cellulite?

Avoid claims that your product can reduce or eradicate cellulite or improve the appearance of the skin covering it. Consumers are likely to expect products and treatments to actually “treat”, rather than simply cover, cellulite and robust evidence would need to be held to support any claims.


While cutting out fatty and sugary foods may lead to weight-loss, don’t imply “detoxing” products such as wraps, patches or devices can aid weight or fat loss as a result of flushing away toxins. Any suggestion that an accumulation of toxins can lead to adverse medical conditions, or that a product can prevent these, should also be avoided.

Miracle clothing

Claims that garments can aid weight or fat loss should be avoided, along with any implication that they are capable of having any kind of permanent effect. Marketers wanting to promote tight-fitting or figure-enhancing garments should focus on short-term loss of girth and the temporary appearance of weight loss alone.

Offence, harm and responsibility

Weight and body image can be a sensitive subject for many, so take care to ensure you don’t include any claims or images that are likely to cause offence.  Also make sure not to appeal particularly to under-18s or to those for whom the diet could produce a potentially harmful body weight (a BMI of less than 18.5).


Hungry for more?  The CAP Copy Advice team, are on hand to give free bespoke advice on your non-broadcast ads.

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