Charaka Samhita 1.41The Ayurvedic healers usually begin the cure of disease by arranging the diet that is to be followed by the patient. So much do the Ayurvedic physicians rely on diet that they declare that all diseases can be cured by following dietetic rules carefully along with the proper herbal supplements; but if a patient does not attend to his diet, a hundred good medicines will not cure him.
Ayurveda, India's holistic, integrated, physiotherapeutic medical system is based upon the universal natural law of balancing the five elements (ether, air, fire, water and earth) that make up the physical body. When one or more of these elements go out of balance because of improper diet and life style, various diseases and mental disturbances can manifest. Ayurveda explains that these five elements are kept intact in the body by three subtle forces called doshas. The key to maintaining physical and mental health is in keeping these elements and doshas in harmonic balance through proper diet, herbs and life style, otherwise early aging and various diseases can manifest. The three doshas are called Vata (sattva), Pitta (raga) and Kapha (tama). These three doshas can even be traced back to the very beginning of creation as representing the three Gods in Vedic wisdom Vishnu, Shiva and Brahma. Vata is the underlying subtle force ruling over ether and air, Pitta rules fire and Kapha is responsible for keeping the water and earth elements in balance. One or more of these doshas or elements will predominate in every individual living entity creating seven possible body types. By knowing which type you are by symptoms the proper diet and herbal treatment can be established for you.
The old saying, "One man's food is another man's poison", is perfectly applicable in Ayurveda, because every food contains these five elements and doshas in different proportions, and our ingesting them will effect our elemental balance in a positive or negative way. Each element by its inherent property, joins with that which is a part of the body. If to much of one element is ingested by a person who already has that element in a sufficient quantity by inheritance, an imbalance can manifest. For example, if a person who has more of the Pitta dosha (fire) eats spicy, sour or to salty foods (which increase heat in the body,) disturbances related to the fire element can manifest. The mind can be afflicted by anger, aggression, impatience, stress, and egotism, and the body can get disturbances like toxic blood, fever, infections, cancer, skin diseases, boils, liver problems and acid indigestion etc. By eating foods and Ayurvedic Rasayanas which have a cooling effect on body and mind, the fire element or heat will be reduced to normal.

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