I don't think airbrush-regulation is the answer. Modelling- and fashion-agencies should take their responsibility and get a grip on what's beautiful.
For instance, Holland's #1 sexsymbol, a bombshell if you ever saw one, got turned down by a modelling agency because she was too short and too fat. For reference-material, google "tatjana simic". Add Playboy to the searchterm for extra references.
Also; in those top-model talentshows, the judges dare call a 185cm tall, 60kg weighing girl "overweight". And this is not even an exception. Everyone is in on it; photographers, casting agencies, fashion designers, every single one.
I'm not even surprised girls nowadays feel ugly. It's not just the adverts, it's the magazines they read. Every fucking fashion-magazine today has an article on how you can look like Nicky Minaj, Beyoncé or who-ever brings teh sexay today. Right next to that article, you can read how ugly you are if you do NOT look like any celebrity.
I compared mags once with a colleague; she was reading Vogue, I was reading Playboy. Her magazine was telling her how she needed to look like Britney Spears (this was in the Oops I did it again-period), my magazine was telling me how the centerfold of that month gets turned on by guys who like potato-chips and play videogames; her mag made her feel depressed, my mag made feel good about myself.