The Tridoshas

The Tridoshas (three doshas) are considered as the primary and essential factors of the human body. It governs our entire physical structure and function. The word ‘tri’ refers to ‘three’ and the term ‘doshas’ refers to the basic physical energies. Dosha, derived from the Panchmahabhutas, is a combination of any two of the five bhutas with the predominance of one.  Dosha are like the elements that cannot be detected with our senses but their qualities can be.
The Tridoshas are Vata,  Pitta and  Kapha and are responsible for all the physiological and psychological processes within the body and mind. These are the dynamic forces, which determine growth and decay. So the tridoshas are used to explain every physical characteristic, mental capacity and the emotional tendency of a human being.
 
Vata includes most of the physical phenomena qualified to the nervous system. Pitta involves the entire chemical process operating in the human body, including enzymes, hormones and the complete nutritional system. Kapha is actually the entire physical volume of an organism, referring to the activities of the skeletal and the anabolic system.
 
Each dosha shares a quality with another; however they show slight differences in the nature of shared quality. The third has just the opposite quality. Also, each has an inherent ability to regulate and balance itself, coming from the antagonistic qualities that arise from the  doshas constituent elements.