I guess I'm on a bit of a tear and am posting like a madwomen today...but that's what happens when you have a good breakfast!
Just wanted to say, good luck w/ that, for your daughter. I was a longtime sufferer of migraines and this helped TREMENDOUSLY. See if you can just get her to make a commitment to it for a measurable period of time. When we think we're giving something up *forever*, without certainty of it *working*, it can be hard to follow or adjust your choices.
But see if she'll just give it 6 months and then review how she feels.