Sugar, alcohol, cigarettes, cannabis.
Out of these, sugar is the most dangerous
I'm diabetic. I get sugar highs once in a while... :-)
Actually, I took large doses of Prednisone for several years for U.C. That's probably why I developed type 2. After having my large intestine taken out, (Yes I can still fart if I stand on my head.) I put myself on a diet and exercise regime, lost 60 pounds and got clean off the insulin. I have normal fasting blood sugars now and I don't take any medications.
Coffee's my drug of choice.