Watch how much liquid you drink with calories. Liquids can make up about 20% of the diet. Of this 20%, sugar sweetened tea and soft drinks often account for about 18 ounces a day. That’s about 100 calories per small eight ounce can or 200 calories a day from soda. This is close to 1400 calories per week or 1/2 a pound of potential weight gain (3500 calories per pound).