How to gain weight when you have a fast metabolism?

Ok so. Im 13 and im a girl and i am underweight. (89lbs) i would really love to be a body builder but i asked that question on here on can a 13 yr old start as one and i saw alot of answers saying i need more weight on Me. But the problem is.....i have a fast metabolism so i dont know how in the world im suppose to gain weight and i eat aloooot and never gain a pound!! Help/answers. Thanks :)

How to Break a Weight Loss Plateau

Recommended Answer:

To gain weight you need to combine protein foods with starchy carbohydrates as indicated below. Good weight gaining combinations are bread, cereals, pasta, rice, potatoes or sweet potatoes combined with meat, poultry, eggs, cheese, nuts or sea food. Peanut butter sandwiches and cheese sandwiches are good weight gaining combinations. The protein in the above combinations will help to gain extra muscles.

Other Answers:

• People think they eat "aloooot" but, just put everything into calories. If you want to gain weight, try eating at least 2500 calories a day. 1 calorie = 4.2 kJ.
• Start eating alot of junk, until you're at the weight of being able to be a body-builder. Trust me. It seems like the only way for people with a fast metabolism to gain weight.