Plain and simple: We just don't feel full by liquid calories in quite the same way as we do real food. Drinking a juice or caramel coffee drink, for instance, won't make you feel full the way eating a bowl of veggie- and protein-packed stir-fry will. So monitor your intake of juice, soda, sweetened coffee and tea, and alcoholic beverages. If you consume each of those beverages during the day, you'll have taken in at least 800 extra calories by nighttime — and you'll still be hungry. (Incidentally, alcohol may suppress the metabolism of fat, making it tougher for you to burn those calories.) Some other ways to skip sugar? Check 'em out here.
Be choosy about carbs. You can decide which ones you eat, and how much. Look for those that are low on the glycemic index (for instance, asparagus is lower on the glycemic index than a potato) or lower in carbs per serving than others. Whole grains are better choices than processed items, because processing removes key nutrients such as fiber, iron, and B vitamins. They may be added back, such as in “enriched” bread.