Although I had CFS, my husband and I were raising foster kids with special needs. Two of them were on a special diet so I kept records of everything we ate. Keeping records helped me discover that, besides the new allergies I kept developing, I had gotten a sensitivity to sulphur. I eliminated everything high in that chemical from my die including all vegetables in the cruciform (cabbage,) lily (onion,) and legume (bean) families, flour containing sulfate, corn, oranges, and tomatoes. Many meds contain sulfite or sulfate and so do some toothpastes so I also had to avoid those.
At first it was difficult to eat while doing without all those foods, but before long I realized my average energy level had gone up to about 70% of normal!
With more energy it wasn't too difficult to cook from scratch once a week and reheat foods the rest of the time. Because the foods that were true allergies and not sensitivities caused mini-muscle spasms and painfully pulled my damaged vertebra out of line I was, and still am, very careful to never make exceptions to my diet. I ALWAYS read ingredient lists on labels, even of foods I've been able to have before, because those often change.
I've told other people with CFS about the great improvement avoiding sulphur caused in my symptoms, but none of them have ever been willing to try it. The diet isn't easy, especially in the beginning, and it's typical of PWCs (People With CFS) to have unusual reactions to things and those vary greatly from one person to another. So maybe that diet won't help everyone.
But it seems to me if there's even a chance that it might make some people's health improve then at least a few of the many with that disease would be willing to make the effort. A month should be long enough for it to show a difference if it's going to work. What can it hurt to try?
If any other PWCs do try a sulphur-free diet I'd love to hear if it helps them.