Different people experience different side effects when eating beans and some people can digest beans better than other people.
Beans contain both soluble and insoluble fiber which is supposed to help your digestive system run smoothly but for some people they're digestive system has trouble with the digestion of beans so it upsets their stomach.
Beans are healthy for your heart and I eat them as often as I can but I too have stomach problems eating too many beans so I can just eat around 7 spoonfuls of beans and then I have to stop otherwise I have an upset stomach.