The 5 Elements
In ancient China, an intricate system of the interaction of nature was developed to help them understand the processes that occur in the human body. While we now have other ways of looking within the body through the development of modern medicine, it is a fascinating insight into the incredibly complicated world of the physical and mental aspects of the body.
The idea of the 5 elements is that we can achieve good health if each of them (Metal, Earth, Fire, Water, Wood) is generally balanced and neither in excess nor in deficit. We can know which of these is predominant because the elements each have their own associations in the body.
Look at Wood as an example. If there is an imbalance, you might have a problem with anger and aggression. Either too much or inappropriately lacking. You might have a green tinge around your mouth when you look carefully in the mirror.
The basic idea is that should any one of the elements get out of balance, you will notice that the associations with that element will be more prominent.