Yes, alcohol and tobacco use increases the risk of type 2 diabetes. While studies show that drinking moderate amounts of alcohol (one drink a day for women and two drinks a day for men) may actually lower the risk of diabetes, the opposite is true for people who drink greater amounts of alcohol. Heavy alcohol use can cause chronic inflammation of the pancreas (pancreatitis), which can impair its ability to secrete insulin and ultimately lead to diabetes. Tobacco is equally harmful. Tobacco use can increase blood sugar levels and lead to insulin resistance. And the more you smoke, the greater your risk of diabetes. Heavy smokers — those who smoke more than 20 cigarettes a day — almost double their risk of developing diabetes, when compared with nonsmokers.