did you try whatever food you bought before you bought it ?
I once bought some Mountain Stuff to try at home.
I loved the Beef Stroganoff it was really yummy, BUT for the next 2 days I wished I was dead, it was far worse cause I was offgrid camping, and I ran out of Toilet Paper.
Fortunately I had napkins and then paper towels.
Your experience reminds me that if one eats lots of MREs you can get constipated.