Alcohol is metabolized differently than other foods and beverages. Under normal conditions, your body gets its energy from the calories in carbohydrates, fats and proteins that need to be slowly digested in the stomach—but not when alcohol is present. When alcohol is consumed, it gets special privileges and needs no digestion. The alcohol molecules diffuse through the stomach wall as soon as they arrive and can reach the brain and liver in minutes. This reaction is slightly slowed when there is also food in your system, but as soon as the mixed contents enter the small intestine, the alcohol grabs first place and is absorbed quickly. The alcohol then arrives at the liver for processing. The liver places all of its attention on the alcohol. Therefore, the carbohydrates (glucose) and dietary fats are just changed into body fat, waiting to be carried away for permanent fat storage in the body.
Alcohol contains 7 calories per gram and offers NO nutritional value. It only adds empty calories to your diet.
Skipping a meal to save your calories for drinks later is a bad idea. Many drinkers know they'll be having some alcohol later, whether going to a bar, party, or just kicking back at home. Knowing that drinking entails extra calories, it may be tempting to "bank" some calories by skipping a meal or two. This is a bad move. If you come to the bar hungry, you are even more likely to munch on the snacks, and drinking on an empty stomach enhances the negative effects of alcohol. If you're planning on drinking later, eat a healthy meal first. You'll feel fuller, which will stop you from over drinking. If you are worried about a looming night out with friends, include an extra 30 minutes of exercise to balance your calories—instead of skipping a meal.
You might think that drinking liquor is more diet-friendly because it has no carbohydrates, while both wine and beer do contain carbs. But dieters need to watch calories, and liquor only has a few calories less than beer or wine. Plus, it is often mixed with other drinks, adding even more empty calories. Hard liquor contains around 100 calories per shot, so adding a mixer increases calories even more.
So basically drinking alcohol causes your body to store more fat.