Eliminate refined sugars, such as candy, cake, ice cream and soft drinks, from your diet. These products are known to drastically increase your caloric intake and cause you to gain weight. When you have a craving for something sweet, drink a glass of prune juice. One cup of prune juice contains 182 calories, which is far fewer than a soft drink. Best of all, the calories in prune juice come from the sweetness in the fruit itself, not from an added sugar source. Remember that while prune juice is far healthier than sugary alternatives, five glasses a day gives you nearly 1,000 calories. Try to drink the juice only when you feel you’d like a sweet snack.