Hi Suzi,
When I first found out that I have RA, I sought help from a Naturopathic Dr in hopes that I could cure it myself. After a year of trying the gamut of supplements and diets, I know that I can't cure the problem with diet alone. HOWEVER, I do know the foods and supplements that make my RA worse and which ones ease the pain.
For me, too much dairy and soy products causes more inflammation and pain, but I can have them in controlled amounts. Gluten (found in all wheat products) definitely causes more inflammation/pain. It's hard to completely give up these products; they're in EVERYTHING. Who knew there was wheat (gluten) in soy sauce?! For me, I only eat gluten on rare occassions, or when someone's made something that looks too good to pass up.
If you're curious and whiling to find out what foods effect you, take them out of your diet completely for a month. Then have one serving of it after a month and see how it affects you. If you notice anything different (ie. more inflammation/pain) then it's possibly making it worse for you. If you don't feel any difference, give yourself a few days (let's say 3) before trying it again. Have two servings the second time but the same principle applies. If you still have no effects and you like the food, I'd keep it in your diet. If it does cause pain/inflammation, you do with that what you want. You can completely take it out of your diet. Or know that when you do eat it, it causes you pain.
Simply to clarify, if you're going to take out soda, you should take out all refined sugars for a month (Good news! You can keep eating 100% honey, agave nectar, and maple syrup). Although this seems like torture, it's only for a month and you'll either find out one of two things. Your body can handle sugar without causing more inflammation, which is GREAT news! Or your body can't handle it and you can be the wiser!
If you're whiling, try it!