Shedding cat 24/7 need help.?

My cat sheds a lot i mean i brush and brush and still its so annoying to have hair all over my house. I love my cat don't get me wrong just wish some one can give me an answer on whats the best thing to do. Shes a calico i have read on other postings that they shed a lot, does it have to do with her food? weather? which i know that's not the case because she sheds all year round. PLEASE HELP!!