Bonnie
I am so sorry to hear your sister has this. I've had it for just over 2.5 years, but only diagnosed last December. I have made changes in my diet because with RSD you need to really watch your body. I've stopped my Diet Coke (I used to drink 6-12 cans a day), but I am fearful of tooth decay and RSD spreading into my mouth from invasive work being done. If you will email me I will send you a link to the four F's diet. Chocolate is not good for RSD, so they say, but it is something I've yet to give up. I believe any healthy foods are important to maintain a healthy immune system. It's hard to ask anyone to give up things they really enjoy. Please don't press her too hard, but be encouraging. She is dealing with a lot right now with the pain of RSD. I listen to my body and do what it tells me. When a bad flair-up occurs I try to figure out of it was due do something I ate, did or just occured. She is lucky to have you.