You may find that regular acidophilus bifidus (pro-biotics) help as they renew all the good bacteria needed in the gut, thus helping the digestion.
I began to be intolerant to wheat in my 50's, was able to manage it quite well by taking pro-bioitics and cutting down on wheat products.
Then decide to cut out wheat completely and was wheat-free for over 6 years and for 3 of them bought artisian gluten-free bread made locally.
Then, for some reason, that too began to affect me and I had to stop eating it, or buy shares in Immodium.
At my dil suggestion I went onto Paleo and that's OK but very firm and only suitable for toast.
Every now and then I try something very light, such as a croissant (wheat) and with the help of the pro-biotics, can manage that.
When I first became wheat-free I researched the effects and discovered it depletes the iron stocks in the body, as does tannin in tea. So if you are feeling unusually tired, it could be as a result of wheat and/or tea.
It also, in some people exacerbates arthritis, so cutting it out of your diet an help in many ways.
BTW, I blamed the additives in commerically made breads, so bought my own wheat, ground it and made my own bread. The negative effects were just as bad.
I agree there's a lot of rubbish added to supermarket bread (even the smell of it in the store turns my stomach) but it is also the wheat itself which can be the problem.