Most of us know what foods to choose - and which to avoid - when trying to lose weight. But the average American gets one-fifth of his or her calories from drinks, so it pays to take a look at the liquid refreshment you choose. It's especially important to stay hydrated when it's hot outside, so keep drinking...wisely. The clear diet drink winner is, of course, water. It's the best way to keep your body cool and hydrated, your tummy full, and digestion running smoothly.

But sometimes we all need a little pick-me-up - so what's the best "energy" drink on a diet? Not energy or sports drinks, surprisingly. They can pack tons of calories, and some energy drink ingredients, especially when mixed with alcohol, can be dangerous. When you need a little caffeine, black coffee and green tea work well. They're high in antioxidants and are calorie-free, plus in moderation, they increase concentration and improve mood. However, when you start adding creamy, sweet fillers like syrups and whipped cream, the health and diet benefits decrease.