Hello, Heather!
Rest assured that Walt Disney World chefs go out of their way to help Guests with any dietary concerns, more so than you can imagine!
First, take a look at this really helpful page regarding
Special Dietary Requests, so that you'll become more familiar with your options at WDW restaurants. When you are at a Table-Service restaurant, be sure to tell your server of your various dietary needs, who will then be happy to have the chef come out to help you customize your plates in a way that's not only healthy but also delicious. I truly believe that WDW chefs welcome such situations as culinary challenges which they can't wait to tackle! You will be truly impressed!
In addition, take a look at a variety of posts on my favorite unofficial site, allears.net. There, hover over "Walt Disney World" tab, click on "Dining" and you'll see a list of topics on the left side. Scroll down to "Special Dietary Needs" and read through some of the articles which pertain to you. I think this will give you an idea of the level of care WDW chefs put into making every Guest enjoy a truly fabulous meal, no matter what his or her dietary restrictions!
Happy dining! Be sure to send more questions as you think of them! I love to help!