Hot on the heels of the Christmas festivities, comes the New Year and renewed commitments to a moderate lifestyle. Here’s some advice to help you make sure that your advertising of diets and weight loss plans doesn’t create a regulatory dog’s dinner. This advice does not look at food or food supplements which claim to aid weight loss; these are covered by our food rules. The main themes of this advice are to make sure your advertising complies with good medical practice, to ensure you hold evidence for any claims and to take care that you don’t appeal to vulnerable people. Without further ado, here are some top tips:


Hold evidence that your diet uses calorie control

Make sure that your diet does not appeal particularly to under-18s or those for whom the diet could produce a potentially harmful body weight (a BMI of less than 18.5).

Take care when advertising diets to obese people.

Hold evidence to show that diet plans are nutritionally well-balanced for the target audience (rule 13.5).

Include the timeframe in a testimonial in which a dieter talks about weight loss if they’re stating exactly how much weight they have lost.

Make sure any rate of weight loss quoted is compatible with good medical and nutritional practice (rule 13.10).

Do not

Make unproven claims for “fad” diets which do not follow the UK Government’s nutritional guidelines.

Suggest that a diet allows people to eat as much as they like and still lose weight (rule 13.8).

Suggest that weight loss will be permanent.

Make general claims that people can lose precise amounts of weight within a stated period (see the Zoe Harcombe ruling; claims in testimonials may be acceptable, though - see tip 5 above).

Claim that weight or fat can be lost from specific parts of the body (rule 13.9).

State or imply that being underweight is desirable or acceptable.

Use any unrealistic or exaggerated before and after pictures or testimonials.

Do not make claims on the efficacy of detox wraps, patches, devices or supplements

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