The TV adverts have been taken off air over claims the British versions of the products do not contain the same ingredients as the American range.
The brand has been endorsed by a number of other stars, including Elle Macpherson and Avril Lavigne. The Advertising Standards Authority (Asa) said: "We noted the ads were targeted at a UK audience and that the UK Proactiv products had a different active ingredient to the US version.
"In that context, we therefore considered the claims of continued use had not been substantiated. We concluded that the ads were misleading. The ads must not appear again in their current form."