answered question 3/14/2010 How Can My 12 Year-old Daughter Lose 20 Pounds In About A Week Or More? Go look up the sacred heart diet. You lose 10-17 pounds per week. It is a very healthy diet because doctors made it up. I hope I helped. And I am 12 years old 5'1 and weigh 113. Is that fat? PLEASE ANWSER!