I don't really have much to suggest other than setup your daughter for success in the future by teaching her to avoid sugar the best she can. Sucrose is something we can afford to completely avoid, there is no nutritional benefit to it in my opinion. Being a gymnast I think requires a bit more "explosiveness" at times, that my be a bit at odds with experimental keto athletes. I've heard good things about these guys and high level training.

Art and Science of Low Carb - jeff Volek, PhD, RD & Stephen Phinney
http://www.artandscienceoflowcarb.com


Good luck. It may be a hard battle when you see things like this hanging on the walls at school. I took a picture of this a few months ago.