The press ad created by Mother featured a photograph of a slim woman's arm and leg and the shadow of her whole body. The text stated: "Super slim No7" and "Anti-cellulite balm a sleeker silhouette in 2 weeks".
The Advertising Standards Authority asked Boots to prove the claim after one complainant, who believed the ad implied the product reduced cellulite, challenged the manufacturer to do so.
Boots sent details of an independent placebo-controlled study, which found that after two weeks' use, 78% of the balm's users reported that their silhouette appeared "sleeker, slimmed and smoothed", and that after four weeks' use measurements showed a decrease in thigh volume and smoothing of the skin profile.
The ASA consulted an expert who pointed out that self-assessment was not strong evidence and that the study showed the measurable benefit of Boots' product over the placebo, a standard moisturiser, was slight.
The watchdog considered that the two claims, "A sleeker silhouette" and "Anti-cellulite balm" were misleading and in breach of advertising codes on substantiation, truthfulness, and health and beauty products.
"We considered that user perceptions were not robust enough to substantiate the '2 weeks' claim and told Boots not to make similar claims, in future ads, that were based solely on consumer perceptions," the ASA said.
Anti-cellulite claims for L'Oreal's Perfect Slim and Estee Lauder's Body Performance Anti-Cellulite Visible Contouring System have also been judged misleading in the last few months.
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