WebMD is a great source for information regarding health conditions. Your doctor is also a great source of information.
Firstly, you can learn it from some healthy books that you can buy or borrow it from the librery. Secondly, you can find it from internet, there are some sites they only talk about the health. At last, you can also ask your doctor who will tell you or give you some information about it.
you could read on health books.
Internet is the only technology from where you can get any kind of health information easily.