CONCEPT OF DIGESTION IN AYURVEDA

Health, vigour, strength and life itself depends on the digestion. Normal activity of digestive power maintains health while abnormal activity leads to disease. A person with good digestive power will have good appetite; can digest even heavy food without having symptoms of indigestion.
Digestion can be defined as “the organic process by which food is converted into substances that can be absorbed and assimilated by the body for growth and maintenance of the body”. It is accomplished in the alimentary canal by the mechanical and enzymatic breakdown of foods into simpler chemical compounds. Digestive process in ayurvedic classicals is aided by the digestive power called “angi”. Agni is defined as the chemical factor, which transforms food into body substances, and the process is called as digestion. The living body is a product of nutrition. The tissues of the body are not similar to that of the food but food is converted into seven dhatus in the body. Tridoshas, seven dhatus (tissues), trimalas (waste products) form the composition of the body. Everything in the body depends upon the balance of these compositions of the body. The conversion of food substances at different levels in various ways till they become tissues of the body is brought about by the agni. There is no tissue building and hence no life or there is no life without agni. Therefore, the life, strength, growth, enthusiasm, development of body tissues, skin complexion are all depend on agni.
Classification of agni:
1. Jataragni – one
2. Butagnis – five
3. dhatwagnis – seven
4. Malaagnis – three

Jataragni:
Agni in our body is generally called as jataragni, which is considered to be the life of a living being. The metabolism of all the tissues of the body depends upon the jataragni. Jataragni is also called as kayagni (that which is present in the body). The functional variations of digestive power can only be inferred can only by the digestive capacity of the individual. Agni is classified into four according to dosha predominance.
1. Samagni: samagni is considered to be the normal angi, which denotes the equilibrium of tridoshas and a healthy digestive system.
2. Vishamagni: food gets digested normally on some occasions and poorly digested in other occasions though the foood is taken normally. This occurs in case of predominance of vata. Persons suffering from this type of agni are more prone to vata vyadhis.
3. Teekshanagni: the person suffers from excessive hunger and thirst and is more prone to pitta diseases as it occurs when there is predominance of pitta.
4. Mandagni: the digestive power is very poor, that the person cannot digest even a small quantity of food. This type of agni occurs when there is predominance of kapha. Persons with this type of agni are more prone to kapha vyadhis.

Location of jataragni: grahani is the location where jataragni is situated and hence called as agniaashaya (the one that holds agni). It is called grahani since it holds the food for digestion.

Digestion of food: pranavata, the property of which is to convey the food form the mouth downwards takes the food from mouth to the stomach. The food is subjected to chymification in the intestines. Jataragni situated in grahani digests the food, which is taken in proper time, proper quantity and proper manner observing all regimen of diet.

Role of bhutagnis in digestion: the body is made up of panchamaha bhutas. Hence the panchabhoutika body should be nourished by the foood, which again is of panchabhouika constitution. The food after being digested by different agnis will in turn enrich the panchabhutas of the body. There are about five more agnis with respect to panchamahabhutas (prithvi- earth, ap-water, tejas-fire, vayu-air, akasha-space)
1. Partheevagni – predominance of prithvi bhuta (earth)
2. Aapyagni – predominance of ap bhuta (water)
3. Taijasagni – predominance of tejo bhuta (fire)
4. Vayavagni – predominance of vayu bhuta (air)
5. Aakashaagni – predominance of akasha bhuta (space)

Jataragni transforms the whole of the food mass into a common digested substance; the bhutagnis will digest their respective substances useful for the formation of different tissues.

Role of dhatwagni: the process of digestion is again continued by the dhatwagnis, which are present in each dhatus (tissues). After completion of digestion by bhutagnis the digested material have to be recognized in different proportions for the formation of different tissues, which is achieved by the dhatwagni (seven dhatus/ tissues) present in different dhatu levels of the body. These dhatwagnis will act upon the concerned nutrients circulating as food helping in the formation of three end products such as
- Gross form – the static dhatus meant for replenishment, growth and action
- Sublte form – the nutrients required for the formation of the next dhatus
- Bi-products/ waste product – the end products that are excreted in due course

Role of malaagni: there are three malas in our body. They are sweat, urine and faeces. They are not merely waste products but are in one way called as secretions also. Malaagni contributes further digestion of food by absorbing excessive water content of faecal matter and imparts natural colour and odour. Similarly mutraagni and swedaagni also contributes to digestion by separating waste after digestion and excreting them. But none of the ayurvedic classics have explained about malaagnis except chakrapanidutta in his commentary of charaka samhita.

Role of agni in formation of dhatus: all the ayurvedic scholars have universally accepted that the dhaus (tissues) are nourished one after another from first dhatu (rasa) to the seventh dhatu (sukra) and food is the main source for the nourishment of all the dhatus. Digestion of food is important as transformation of dhatus depends on proper digestion of food. Dhatus plays an important role in maintaining the equilibrium (health) of the body. Hence digestion (agni) has a vital role in the proper transformation of dhatus. Agni is praised as God itself in ayurveda. Agni is subtle in nature and transforms the food substance sun unexplainably to suit the physiological and psychological requirements of the individual. Maintenance of health depends upon the power of digestion, as proper digestion of food only can form proper formation of seven dhatus and tridoshas, which are the composition of the body. The food that we take should be properly digested by the power formation of the composition of the body. The food that we take should be properly digested by the power of digestion – the agni that could help in proper formation of the composition of the body. Improper digestion will lead to improper formation of dhatus, which further lead to many diseases in the body. Moreover, if digestion is good, only then proper assimilation and absorption of food can happen. In case of any disease the power of digestion is taken into account for proper assimilation and absorption of medicine that is administered, to server the purpose. Hence agni is important in every individual for healthy long life.
Note: when the power of digestion – agni is not good or when you don’t feel hungry should not eat and wait until you get proper hunger. Proper digestion can happen only when we take food with proper hunger. If food is taken when there is no hunger or heavy food is taken when there is less hunger will lead to indigestion further to any disease to the body.

Dr. S. Brindha BAMS
Global ayurveda (Dec-Jan 2007)