If there is a corn sensitivity, it could be getting you in many ways. Fish are caught and put in a vat of corn based citric acid/water for the trip to land. Many 'tuna in water' really isn't 'water' but vegetable broth. Vegetable either being corn or soy. Then there is the can lining, as mentioned. But I would guess your mayo has corn also.
I personally have found that since going gluten-free I can eat some things that used to kill my gut. Like citrus no longer bothers me. But then there are things I seemed ok with before gluten-free (and CF) that I can no longer tolerate. My best advice is listen to your body. If it says DON'T, then don't try to force it to say YES.
That is what happened to me. In my case, I traced it to corn intolerance also. I found going gluten-free was easy, this is the best day/time in the world to do that, as more companies are careful to label things gluten-free. Its not the same with corn, there are many derivitves of it, hiding under other names, and it is used in/on nearly everything. Going on a clean unprocessed diet is not much help, because, for instance, fresh produce is sprayed with corn, meat processors use corn based cleaners.
Good luck finding your answer. You might want to look at corn next. Celiac and corn intolerance seem to go hand in hand.
I feel your pain. I went gluten-free, thought, hey, this is no big deal! Then the realization of the corn, dairy, then soy.....
In my case, just avoiding the actual corn, corn meal, corn starch, etc is not enough. Even the itsy bitsiest bit of citric acid in something makes me gain 10 lbs overnight and takes three weeks to go away. So discouraging! I was healthy two months out of 10, and that was when I only ate from my garden. No garden now.... ugh.
To address constipation, for those who have it.... make sure you get enough magnesium. That helped me. Then I got a fiber called Heathers Tummy Powder. Nothing like psyllium (which my body began to reject), it actually feels soothing to the guts, instead of violent. Also, I began ground flax meal daily trying to get Omega 3s, and that is helping also.
I also had to cut out all dairy for 6 months. I got brave enough to try butter again, and have not reacted to it or whipping cream. (the fat of the dairy)
For insomnia.... this was a duh moment for me. I always slept 10-12 hours a night, before I stopped grains. I now realize I only need 5 hours of sleep at night. I set my alarm to wake me up at 5 am, so I don't oversleep and cause trouble the next night... and I go to bed at midnight. My tossing and turning has stopped, I now sleep when I am in bed. Ahhhh......
Hang in there, everyone! It has GOT to get better. At least I am hoping it all will.
Raz, I feel your pain! Although I didn't think gluten was hard. I thought it was a piece of cake. I kept good spirits about it! But that was easy, then, because I suddenly felt so well.
I shouldn't have gotten used to feeling well I guess.
Just when I think I have done 'everything right', I get corned again. When people ask me what I eat, I joke... the lawn. I am beginning to feel that is all I will be able to eat.
Things look even bleaker when you are battling the pain.
Somedays I don't even bother to eat.... it actually makes me feel better......
If I may update? I posted in June. I have been gluten-free since early February 2012, grain free since March. I have not been accidently glutened onceI But by corn, yes, many times. I also gain about 10 lbs (of fluid and inflammation) within a few days of corn exposure (and it can be as teeny of an amount as in a vitamin pill).
I hadn't lost weight in June, but since then, I have lost 34 lbs.
Grain free, dairy free.
I eat lots of coconut oil and eggs. I sometimes don't feel hungry, and I know I am way below the calories I should eat in a day, so I will add extra coconut oil to make up my calories.
It has seemed to work!
I just wanted to feel better, even though I needed to lose weight, I'd given up trying. Yet it just melted away. I am normal range body fat for the first time since I was 26! (I'm 51)
I won't ever even try to add them back to my diet. I see no need ....