Is There a Restrictive Diet for Autoimmune Diseases?

I have multiple autoimmune diseases myself and I know how draining and painful the symptoms can be. When we seem to feel better on a restrictive diet, often it isn't actually because of the diet itself. These factors include the placebo effect in which believing that an inert treatment will make you feel better actually does. Another reason some people might perceive integrative and functional and alternative treatments to work is that many chronic diseases go through normal fluctuations or cycles where symptoms will get worse than better than worse again.