Diabetes is typically seen thru Jupiter and Venus. When we consider that the pancreas metabolizes sugars with insulin and fat with glucagon then is seem reasonable that these two sweet lovers would be involved with diabetes. I typically like to see the 2nd house to get a sense of their diet. Jupiter also rules over the liver which is also affected by poor diet: saturated fats and too much heat and toxin like alcohol, coffee, natural and pharmaceutical drugs and tobacco.