Proof that a calorie from one source is not the equivalent of a calorie from another—imagine getting nearly all your energy and nutrition from alcohol. Some college kids are. “This is big among college girls right now,” says Dr. Stratyner. “They won’t eat all day so they can consume large amounts of alcohol at night and not gain weight.” Stratyner says drinking on an empty stomach can throw off blood sugar levels and cause a dangerously strong state of intoxication, as well as a more powerful hangover. In addition, alcohol combined with malnutrition may further inhibit the body’s ability to get the necessary nutrients it needs to function.