Hi there can you tell me what the recommended calorie intake is for a 15 year old boy and girl. My twins have something against eating and I do not know how to change their minds. I ask them if they do not like the food but it is not like that. How do I make them eat, they are not becoming thinner or losing weight yet. At the rate they are going, they are going to become week soon. I am giving them vitamin tables, it is not like they do not eat all, and it is just that their appetite is not so great for 15 year olds. They do not even eat junk food surprisingly.