I get the tummy thing if I have a dairy milk coffee, even though I don't usually have issues with dairy milk, which is odd, but I prefer coffee with soy anyway since menopause for some reason. It's weird for me; I'm one of those people who can have 3, 4, 5 cups of coffee and it doesn't seem to do a damned thing, but a cup of caffeinated tea will keep me up (and piddling for Australia lol). I love my coffee and, as a former barista, will never give it up, but tea is my real poison. Especially love me a genmai cha. I have a lot of different teas. The tea aisle is my weakness and I have to avoid it, I just want to drink them all. I could talk tea and coffee for hours!