The average American consumes 3 pounds of sugar a week and 130 pounds a year, reports Forbes.com. This is equal to about 3,550 pounds of sugar in a lifetime. The consumption of added sugar accounts for an intake of 500 calories per day, which can cause a weight gain of 1 pound per week.his means that there is no minimum amount you need to take in each day, but there is a maximum. These recommendations are based on gender. Women should limit sugar intake to no more than 6 teaspoons per day, which provides about 100 calories.