This is the theory of Yin Yang

THEORY THAT Yin: Yin A healthy balanced in all aspects of life.
The theory of Yin THAT into basic philosophy of acupuncture treatment / massage acupuncture also includes all the materials or objects with their symptoms, which exist in the universe, all matter and its symptoms can be grouped into two groups /, a large group. Therefore are manifold, then to make it easier to remember both parties of the things mentioned above, named by the Yin and IS groups, such as naming a pre-existing.
Yin and Yang are the two pieces of material or object with the symptoms, the nature of the underlying mutual, mutual influence, mutual support, mutual attraction, not absolute, and most importantly, they contradict each other but form a unified whole in a harmonious and balanced dynamic.
Examples of Yin THAT:

In the universe
Yin: dark, night, water, wet / moist, cool, down, in, west, north.
A: Light, noon, fire, dry, hot, top, outer, east, south.
In disease
Yin: Chronic, quiet, long, cold, damp.
A: Acute, nervous, new, hot, dry.

The nature of Yin THAT
If we look carefully the two groups above, we can draw the conclusion that, someone can be considered healthy if the yin and yang in harmonious life. The loss of the balance of Yin and Yang in the body or life, will result in an abnormal state in question. In the science of acupuncture massage this situation called abnormal disease / illness. So that meant someone was sick at the loss of the balance of Yin THAT.
[Quoted from the debriefing of the pension book PLN]
An interesting theory that a healthy life style Yin THAT, in the teachings of a religion that is Islam teaches a balance in life and lifestyle. Like a prayer "please happier world and the hereafter" the advice from the sunnah of Prophet how to eat a good procedure that is without excessive eating enough to keep the stomach contents and dividing into three parts / spaces are:

1. One part for the Air [1 / 3 stomach to Air]
2. One part for the Water [1 / 3 stomach to Drinking]
3. One part for food [1 / 3 stomach to eat]

Also mentioned in the Qur'an that which won the World happiness [healthy] and happiness of the Hereafter are those whose souls are calm and clean hearts of various kinds of thoughts are harmful and vain.
From the theory of Yin Yang and the exposure of healthy living Islami above quote can be concluded that the key to a happy and healthy life is a balance between Yin THAT dala all aspects of life, in the Islamic world and the hereafter balance, not so love the world nor leave the world. So the "peace of mind will create happy and healthy life."More Information : www.goloox.com