One big concern about this is that the messages the media send to young girls are anything but positive. Pressures about image and consumerism are rampant. Girls may feel they can’t measure up. It’s not surprising because the media images are not just unrealistic, but often completely false.
There are some fascinating sites online that show just how invalid media ideals can be. Check them out with your own daughter, and have a conversation about what the media is presenting as beautiful. Jamie Lee Curtis started the whole discussion years ago, by allowing photographers to document her appearance before and after a team of experts polished up her appearance. Dove has a great campaign including a fascinating video called Evolution, showing how makeup and Photoshop transform an attractive, but normal, young woman into a billboard image. There are other sites that show some of the worst offenders of modified images from magazine covers.
You can't change what your daughter finds fascinating, but paying attention and connecting over her interests can make a positive difference in your relationship and her self esteem.