One drink at happy hour can help you unwind after a tough day at work, but these liquid calories add up. Mixers and juices in many cocktails can be especially high in calories. This is an odd piece of dieting advice, but if you prefer hard liquor, order your drink straight up or on the rocks. Sip and savor a high-quality shot of tequila or a whiskey on the rocks, which is about 100 calories. Since the flavor of these alcohols are intense, it should take you a while to drain your glass. You'll end up milking it for the entire cocktail hour or over dinner, rather than kicking back a few rum and cokes. Remember, women should only drink one alcoholic beverage a day, more than that and you could be harming your health.