My fruit intolerance is not caused by toxins, but rather by my bodies inability to produce an enzyme that is essential in the breakdown of fructose or sucrose. My allergy is a hereditary dysfunction of my organism; no fasting could ever help with that. I also never had problems with milk (I got tested for many things and milk is not one of my foods intolerances), so I'm skeptical to think having too much lactose would be that bad for my organism. But my real question is that I know that you can have ketosis even when you eat, but I was wondering that if I drink milk I whether or not my digestive system will shut down like it happens with other fasts.