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.

Marketers have claimed that their skin creams can have a cumulative and persistent effect on the skin. Claims of this nature can include “Moisturises your skin for X days after your last application”, “Reduces the appearance of lines and wrinkles by XX% in six weeks”, “Reduce the appearance of wrinkles in just X days”, “Look 5 years younger in just a month”, “Regular use stimulates cell renewal” or “Over time skin will become more radiant looking”.

In 2008, the ASA upheld complaints about an ad that claimed "…[our cream has] been proven effective for reducing wrinkles and smoothing facial skin by up to 60% in just one month … skin thickness increased by over 8% in four months … In vivo testing showed that applications reduced wrinkles around the eyes by as much as 20% after two months and by more than 60% after 4 months … it repairs the matrix and epidermal junction to reduce wrinkle depth by 40%". The ASA considered those claims implied more than merely a cosmetic effect, and that consumers would understand from the ad that the product could provide a physiological action with a cumulative effect (Age Technology, 5 March 2008).

More recently, in 2018, the ASA investigated ads with multiple claims for an eye cream, including Before and After photos and the claim “dramatic results instantly - and the results get better after every use”. The ASA considered that this claim, and the overall context of the ad, suggested that consumers should be able to see an instant effect on their skin as soon as they applied the product, with a cumulative effect occurring over time. However, the evidence submitted by the advertiser was not sufficient to substantiate this claim, nor any of the others made (The Perfect Cosmetics Co Ltd, 19 December 2018).

Both the ASA and CAP accept that, in theory, when used on dry skin, moisturisers have the potential to demonstrate a cumulative and persistent moisturising effect. After repeated use the skin could become increasingly moist and plumped with moisture, but, although we accept that this is possible, neither the ASA nor CAP has yet to see any convincing evidence that a moisturiser can produce this effect. Marketers wanting to claim a cumulative or persistent effect would need to provide product-specific evidence (merely presenting ingredient-specific data might be considered inadequate). They should be aware that the level of evidence is very high; for example, trials might need to be carried out on the target market (to control for age and gender), the relevant area of skin and the relevant skin type. Any claimed benefit, such as “reduce the appearance of wrinkles by 67% by week 6” should be visible to the consumer or an impartial observer. Both the ASA and CAP are unlikely to accept such claims if they are technically true but the effect is so small that the average consumer is unlikely to perceive any change or benefit. See here for guidance on the level of substantiation expected for these sorts of claims.

Marketers should note that neither the ASA nor CAP has been convinced that the application of a moisturiser to normal (as opposed to dry) skin has been demonstrated to have a cumulative or persistent beneficial effect.

See also Beauty and Cosmetics: GeneralBeauty and Cosmetics: CreamsBeauty and Cosmetics: Physiological Effects, Healthcare: Medicinal Claims and Beauty and Cosmetics: Use of production techniques

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