A number of people, even doctors, have expressed surprise that I don’t have problems digesting dairy products. There is a common belief that people with Crohn’s are lactose intolerant.
Lactose is broken down by lactase, and lactase is produced in healthy epithelial cells in the small intestine. (The exact kind of epithelial cells involved are called enterocytes). When a person’s small intestine is very inflamed and/or ulcerated, these cells can’t do their job, and lactose intolerance develops. But when inflamed or ulcerated patches are separated by healthy tissue, a person can still break down and absorb dairy products containing lactose — assuming that they’re not lactose intolerant to begin with.
There have been times when I was very ill that I have been temporarily lactose intolerant. It took weeks to months after successful treatment for the damaged cells to grow back. When I was at my worst, I couldn’t even handle butter even when I took lactase pills with my food.
Right now, though, I can still eat dairy products without bloating or feeling ill — though I can’t say the same about most vegetables.