For the entire range of digestion, metabolism and assimilation activities in the body, there are thirteen types of biological fire (agnis) probably exhibiting enzymatic, hormonal and chemical functions at different levels from systemic to cellular level of the body. These thirteen types of agnis (biological fires) are grouped into three categories:-

1.     Jatharagni or Koshthagni or Pachakagni: for digestion of food.

2.     Dhatvagni: seven types for specific tissue metabolism.

3.     Bhutagni: five types for finer molecular metabolism.

Jatharagni or Koshthagni or Pachakagni is located in gastro-intestinal tract and performs the proper digestion of food. Food consumed will not provide good health unless it is digested properly. Even if the food is of high quality and pure, it will be harmful to the body if it is not fully digested. The jatharagni represents all the enzymes and chemicals produced in or poured in the gastrointestinal tract. Jatharagni is considered as the master agni and it governs the function of all other agnis besides its own functions.

Jatharagni And Other Agnis:

Jatharagni is the most basic of Agni. After its action on food, it turns into Ahara rasa, then Bhutagni works on it as catabolic processes inside various tissues, and Dhatavagnis work on it as anabolic processes inside seven tissues to build them up. Together these two types of Agnis work as complete metabolism going in our body.

Seven dhatvagni are located in respective dhatus (tissues) namely:

  1. Rasadhatu (nutrient fluid) – Rasagni.
  2. Rakta dhatu (blood tissue) – Raktagni.
  3. Mamsa dhatu (muscle tissue) – Mamsagni.
  4. Medas dhatu (Adipose tissue) – Medo agni.
  5. Asthi dhatu (Bony tissue) – Asthyagni.
  6. Majja dhatu (Bone marrow and nervous tissue) – Majjagni.
  7. Sukra dhatu (Reproductive tissues including sperm and ovum) – Sukragni.

Seven dhatu agnis are responsible for the formation of tissues (dhatus) and participate in the specific tissue metabolism. The dhatvagni represent the entire range of anabolic processes functioning in the respective tissues.

Five bhutagni are fine and subtler agnis located in the five mahabhutas. These agnis are responsible for the molecular metabolism and help in synthesis and break down of materials at molecular level. These represent the catabolic processes in our body.

Of the thirteen types of agnis, the most important is the digestive fire/jatharagni. The concept of the digestive fire (jatharagni) is significant due to the central role of the digestive process in the functioning and formation of nutritive fluid (ahara rasa), the physical elements (doshas), tissues (dhatus), and wastes (malas).

Due to faulty agnis, a number of unripe, undigested or unmetabolised byproducts are formed and have tendency to block the micro channels of the body, thus resulting in accumulation of doshas and finally precipitate in the form of disease.

Ayurveda emphasizes that most of the diseases are the product of faulty agnis that is why the main principle of treatment of all diseases in Ayurveda is to restore and strengthen the agnis (digestive and metabolic fire).