A 2016 project by the ASA looking at sexism in ads identified six categories of gender stereotype: body image, characteristics, objectification, roles, "sexualization" and mocking those who do not conform to male and female stereotypes.
While female stereotypes in society (not just in advertising) have begun to be addressed, inequalities "still pervade many aspects of society," the ASA's report states. Male stereotypes in general can also have a negative effect on men and boys, it adds. "For example, stereotypes that imply men should be physically strong, unemotional and capable of being the main breadwinner in a family are linked to outcomes such as depression and suicide."
The ASA also commissioned researcher GfK to undertake a study of men and women in ads, examining adverts from brands including Calvin Klein, Topshop, Doritos, KFC and Lynx. GfK conducted focus groups as well as one-to-one interviews with 157 people across all ages.
It found that 13 to 14 year-olds were aware of gender stereotypes among children and the limitations these might impose, among other findings.
On seeing an ad for sportswear, one teenage girl commented: "I'm angry because I guarantee people aren't going to be the same as the people on that poster and I'm upset because I feel that I should look like that but I don't, and it's making me feel wrong."
The move follows various advertiser initiatives such as the recently launched "Unstereotype Alliance", an international collaboration between UN Women and companies including AT&T, Facebook, Mattel and Unilever.
AT&T's chief brand officer Fiona Carter has spoken of the company's responsibility in removing stereotypes, after reviewing the casting suggestions for a 2015 ad. "I realized that the casting… we had less than 50 percent women, they weren't in speaking roles, the positions of authority were white males and secondary positions were people of color or they were women.
"For me that was a personal moment when I realized I had the power and the responsibility to make a change," she said, speaking at an event at the Cannes Lions advertising festival last month.
The new U.K. rules will be created by the Committees of Advertising Practice (CAP) before the end of the year, and they will come into force in 2018. The ASA then has the responsibility of enforcing them.
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