Sun, Mars, Ketu (South node of moon)
Sun: It governs the fire element in the body, providing light, heat, and colour on all levels. It rules over all pitta system viz digestive system, eyes and perceptive aspect of the mind. Sun is an indicator of our physical vitality, good health and prana resistance towards diseases, digestive power and metabolism of our body.
Mars: It governs Pitta more specifically, particularly through male masculine energy, which is fiery & aggressive in nature. It is a natural malefic planet, more likely to cause pitta type diseases. E.g. fever, acute inflammatory conditions. It also causes reckless action and accidents. Mars is very important planet to be examined in match making especially for sexual temperament between couples.
Ketu: It is said to resemble Mars in its influence, but in a more subtle way. It governs diseases of unknown etiologies, rare diseases (difficult to diagnose), and neuromuscular disorders. Also indicates wound, acute injuries. Ketu is very important in our life to balance our obsession and desires (Rahu)