What are the causes of very bad smelling flatulence and stool? I don't have diarrhea, but I am constipated. The gas has lasted for a couple weeks.

I'm sure you know.. ...that flatulence is normal; many consider it to be a sign of a healthy digestive tract. The usual gases, nitrogen, oxygen, carbon dioxide, hydrogen and methane aren't too bad, but when sulfates are added, it smells worse. When gas in bowel for extended time, bacteria adds sulfates, as do foods high in sulfur.Avoid veggies from cabbage family (broccoli, cauliflower, etc). eggs, cheese garlic, etc.