Am I really too slim?

I think my size is just nice but my family always says that I'm too slim. It can get so frustrating sometimes. My dad even compares me with those starving people in Africa. That's a major exaggeration and really annoys me. -_-I mean, come on, there are people slimmer than me. And I eat three proper meals a day. In fact, it's a personal policy for me not to skip any meals. I don't starve myself. What is wrong with wanting to eat in the right proportions and not the excessive amount that they sometimes prepare for me (more suited for a guy)? It's not as if I'm on a diet or anything. In fact, I didnt slim down on purpose at all. So why can't they understand that?

Sighx. Sometimes, I really feel so misunderstood.