LONDON — One ad for baby formula showed a little girl growing up to be a ballerina and a little boy becoming a mathematician.

Another ad, for a weight-loss drink, asked if viewers were “beach body ready” and showed a bikini-wearing woman whose bronzed image, critics said, promoted an unrealistic standard of beauty.

A third ad, for the video game “Game of War,” showed the American actress Kate Upton scantily dressed on a horse, making it seem as though sexual desirability were a prerequisite for leadership.

Britain’s advertising regulator, reacting to these ads and similar ones, announced Tuesday that new rules would be developed to ban advertising that promotes gender stereotypes or denigrates people who do not conform to them; sexually objectifies women; or promotes unhealthy body images.