At 7 calories per gram, alcohol is quite fattening and provides zero nutritional value. Besides the waste of calorie consumption, alcohol negatively affects the body’s ability to turn food into energy. After alcohol is consumed, your body processes that first before digesting your food (fat, carbohydrates, and protein). Because it is processed and digested first, drinking alcohol slows down the fat burning process, therefore hindering your fat loss goals.

In a study published in the American Journal of Clinical Nutrition, 8 men were given two drinks of vodka and sugar-free lemonade in half hour intervals. Each drink contained less than 90 calories and fat metabolism was measured both before and after consumption of the drinks. For several hours after drinking the vodka, whole body lipid oxidation which is the rate at which your body burns fat was reduced by 73% [1],!

To make a long story short, alcohol and fat loss do NOT mix!

References:
1. Siler, S.Q., Neese, R.A., & Hellerstein, M.K. (1999). De novo lipogenesis, lipid kinetics, and whole-body lipid balances in humans after acute alcohol consumption. American Journal of Clinical Nutrition, 70, 928-936