I'm going to chime in here on the gluten free diet. I've recently been diagnosed with Celiac and have been attending classes on how various foods impact our health (beyond gluten free). There is quite a link between celiac and other autoimmune diseases, including lupus and MS. Celiac disease can create quite an overlap of symptoms that show up similarly to the symptoms we all experience here. I ignored it for years because I thought the main symptoms were GI related, but that is often not the case. Muscle aches and pains, joint pain, brain fog, fatigue, headaches, .....the old familiars...are among the common ones, along with thyroid problems and osteoporosis. The malabsorption it causes creates numerous issues. Undetected Celiac can often progress to AI problems as well as cancer. According to my doctor, medical students spend about 20 minutes on Celiac, and then long careers missing or ignoring the signs and symptoms.
Along with a gluten free diet, it's important to eat fresh, locally, and seasonally whenever possible, eating as few processed foods as you can manage. Omega 3 eggs - lots of fish, very little in the way of vegetable oils, and not as much poultry as is generally advised. Because of the way it breaks down the corn diet - it is loaded with Omega 6. Which is another whole subject. We are overloaded with Omega 6's in our diet and need to reduce them and increase Omega 3. Avoid artificial sweeteners as well as the "natural" ones like Stevia. Flax seed has lots of Omega 3, but we don't break it down advantageously, so it's better to eat the Omega 3 eggs (flax seed fed chickens). The hardest for me has been giving up nuts, seeds and garbanzo beans (i.e. hummus). All of this is because of the high amount of Omega 6 they contain.
http://efaeducation.nih.gov for Omega 3 vs. Omega 6 info and guidelines. Good luck - starting while you are still young is the best thing you can do.