I have always had loads of thick long curly hair since a nipper, I am now 36 and have also lost hair by the handfull each day since mid teens, If I brush it it comes out even more - I have just accepted this as normal for my hair as it never looks any "smaller" for my daily hair loss.
If yours is the same ie thick and full I really wouldnt worry about it that much, my Dad used to say that our hair is like Dogs coats - after all there are loads of different breads and some moult more than others! Not perhaps a comforting analogy but true non the less !