If your concern is about body image and stuffs, then I think you should worrying more for those in adult age.
At least those teenagers still live with their parents or guardians, which then could oppose them or giving them some other point of view. They still had someone that are in control or at least checking them out.
But for adults? Nah. You live on your own. And unlike teenagers or kids, adults could have the money and resources to do all of that and there are almost no one to stop them (unless they are living with some partner that had a clear mind regarding this)