It corresponds to metabolism of western physiology and is roughly synonymous to bodily fire. All metabolic processes in the organism are pitta mediated. Thereby it governs all metabolic transformation in the body involving digestion, absorption, assimilation, nutrition, temperature, skin colour, lustre of the eye, intelligence and understanding. Through it are aroused anger, hate and jealousy. Energy being the underlying requirement of all metabolic activity, fire is a component of pitta. Lack of it is represented by the quenching attribute of fire, which is water. Thus pitta is said to be constituted of tejas and ap. Due to catabolic action and heat generative activity of tejas, pitta is laghu and tiksna. The bonding and binding anabolic reactions of Ap impart snigdha, drava and sara properties to pitta. With these primary qualities, the seat of pitta is stomach, duodenum, liver and spleen, governing the area between the umbilicus and the diaphragm. Depending upon its location in the economy pitta is of five types of which the first two are grosser forms, while the others are the subtler ones.

1. Pachaka agni – Established in the stomach and duodenum it enables digestion of ingested food and guides the manifestation of all subsequent forms of energy resulting from digestion.
2. Ranjaka agni – Residing in the liver and spleen, it is associated with metabolism involved in the formation of blood, bile, semen etc.
3. Bhrajaka agni – Residing in the skin it is involved in bodily temperature regulation and imparts a natural glow to the skin.
4. Sadhaka agni – Situated in the heart, it drives away tamas from it enabling cardiac activities. Also it is instrumental in proper functioning of memory and intellect through its cerebral activities. Finest of all pittas, sadhaka agni enables comprehension, cognition and sensory perception.
5. Alochaka agni – Exerting its functions on a subtle (sukshma) plane it enables metabolism associated with visual perception.