"Are you beach body ready?"

It's a slogan that has inspired a torrent of protest in the UK. It was run on an advert by British company Protein World, which sells weight loss products, alongside an image of a model in a bikini.

An online campaign and a frenzy of protest eventually got the ad banned. But is this a sign that digital protest is changing the world of advertising? The BBC's Elizabeth Hotson has been finding out.