Help pleast, what are the best supplements for teenage girls?

[pinkbraces]

My 15 year old daughter is studying for her GCSE's, she is pretty stressed out, which is unlike her. Her energy levels are low, I have had her checked out for aneamia and she is fine. I think a supplement would be good to help with her energy levels, she currently takes Omega 3 with added vitamins. Her diet is pretty good although she doesnt eat any red meat. Would really appreciate some advise. thanks