Alcohol

As if it wasn't already common sense... alcohol = bad. But here's why:

When you drink, a small portion of the alcohol is converted and stored as fat, and the rest is converted into acetate. Acetate is then released into the bloodstream and used instead of fat and glucose as a source of fuel. So you automatically store some as fat that you can't even burn because the rest of the alcohol is used for energy, which in addition leaves a large amount of excess fat/glucose calories that are just stored as glycogen... which tend to resemble love handles. Not to mention that alcohol is a diuretic and dehydrates you.

One shot = 100-200 calories.
One beer = 120-200.
One glass of wine = 80-140.
One cocktail = 250-600.
A typical relaxed night? 500. The more common binge night? Probably closer to 1000.

Anyway, I doubt this will change my habits.