The issue with alcohol in particular is a biochemical one. Ethanol is chronically slightly poisonous, but methanol is acutely very poisonous. If you drink etha

The issue with alcohol in particular is a biochemical one. Ethanol is chronically slightly poisonous, but methanol is acutely very poisonous. If you drink ethanol all your life you may get cirrhosis of the liver and have elevated risks for other diseases, but if you drink even a small amount of pure methanol you’ll go blind or die. So alcohol prohibition decreases chronic disease due to less ethanol consumption, but increases acute disease due to more accidental methanol consumption. At least in populations that don’t already have strong cultural norms against alcohol consumption. Many other vices have this duality of harm, but alcohol’s is particularly one-sided.