CONSEPT OF AGNI (DIGESTIVE FIRE) IN AYURVEDIC AND MODERN PERSPECTIVE.
Prof.Dr. R.R.deshpande. (MD in Chikitsa and kriya sharir)
HOD & Guide (Kriya sharir department)
Address – 9/A, Kapila Society, Gokhale nagar, Pune-411016
Mail id – firstname.lastname@example.org
Ayurveda, Indian system of medicine is popular and well know globally. Basic reason is the fundamental principles of ayurveda have proved their time tested importance. One of them principle is, role of Agni or Digestive fire in the body. Ayurvedic compendia have explained details about Agni (Digestive fire), Sthula pachana (Primary or gross digestion) & Sukshma pachana (Tissue metabolism). For treating any patient, understanding of Agni concept with contemporary knowledge of modern medicine will be immensely helpful.
While explaining the importance of Agni ayurveda quotes “Rogaha sarve api manda agnau….” (Ashtangahrudaya, nidan sthan 12), this means all the diseases are created due to weak digestive fire or faulty metabolism.
This article is an attempt to explain ayurvedic Agni concept in more vivid manner & clarifying some points with the knowledge of modern physiology.
(References no.- 13)
KEY WORDS – Agni, Jatharagni, Bhutagni, Dhatwagni, Pachana, Digestive juices, Metabolism, Dhatu poshana nayay.
Agni concept is important in healthy condition as well as in diseased condition. According to ayurveda the person is called healthy when he has balanced condition of Dosha (Bio energy), Dhatu ( Body tissue), mala (Waste products) & Agni (Digestive fire).
Functions of Agni –
When digestive fire is working efficiently, the person can enjoy the benefits of its normal functions. These are explained in charak chi. 15/2. From excellent digestive fire or Agni person will get a Long healthy life (Ayu), Health (Swasthya), Physical strength (Bala), Energy (Utsaha), Proper nutrition & growth of body (Upachaya). Normal metabolic process will be reflected externally as well by radiating skin color, complexion & texture. Not only this benefits but Ayurveda explains that even life & death condition of person depend on normal Agni. This means when body metabolism is extremely distorted it can cause death.
Ayurveda believe that Agni is like fire, a form of thermal energy. Energy requires medium to perform it’s normal function. For example, electrical energy can be experienced by moving fan and blowing lamps similarly Agni, Thermal energy works through the medium of pitta dosha (Ref. Agni reva sharire, pitta antarrgataha kupita akupita……………. Charak sutra sthana 12) In this verse (shlok) dual functions of Agni are explained i.e. physiological & pathological functions.
Physiological condition of Agni will be responsible for – Digestion, normalcy in vision & body heat, normalcy of complexion, valour, joy & happiness etc.
Pathological condition will be responsible for- Indigestion, loss of vision, Hyperpyrexia, abnormality in colour complexion, anger, sorrow & anxiety etc.
Types of Agni-
In each cell of the body, conversion & metabolic process is taking place, which occurs due to Agni. So, ideally we can say there is Innumerable numbers of Agni’s like Innumerable numbers of cells. But for practical purposes mainly 13 types of Agni’s are explained as follows –
1) Jatharagni – 1
2) Bhutagni – 5 ( Parthiwagni, Apyagni, Tejasagni, Vayavagni, Akashiyagni)
3) Dhatwagni – 7 (Rasagni, Raktagni, Mamsagni, Medagni, Asthiagni, Majjagni, Shukragni)
Where & how these Agni’s work?
Sthula pachana (Primary digestion or Gross digestion) –
It takes place from mouth to large intestine. Digestion is a transformation or parinamana in Sanskrit. Digestion converts heterogeneous substances to homogeneous substances. For example, proteins are converted into amino acids, fats are converted into fatty acids & glycerol and carbohydrates are converted into glucose.
Ayurveda explain the same thing in its own language. For example, Wheat is parthiv i.e. nutrious substance. But it is useful only when it is converted into body assumable form. Ayurveda says this conversion take place in five forms like shabda (sound), sparsha (touch), rupa (dimensions, appearance), rasa (taste) & gandha (smell).
Conversion in structure, taste & smell can be easily understood by available instruments & chemicals. But change in shabda (sound) & sparsha (touch) is comparatively difficult to prove by present available investigations. It may require sophisticated or ultramodern techniques. For example, when wheat is converted into glucose, to test change in the sound we will need an instrument, which can record sound waves oscillations of wheat molecule & glucose molecule.
Digestion & conversion is taking place from mouth to large intestine. Ptylin is present in saliva which converts starch into Dextrin & Maltose i.e. why even if we chew a slice of bread or piece of chapatti, only you can feel its sweet taste. Gastric secretions contain Pepsinogen which is converted into Pepsin with the help of HCL. This Pepsin acts on proteins & converts it into Peptone & Proteoses. Gastric Lipase breaks the short chains of Triglycerides in Fatty substances.
In pancreas, with the help of Enterokinase, Trypsinogen is converted into Trypsin. This Trypsin acts on Chymotrypsinogen & form Chymotrypsin. This Chymotrypsin acts on Peptone & Proteoses & Diapeptides are formed. Pancreatic Amylase acts on Starch & converted it into Dextrin & Maltose. Pancreatic Lipase acts on Triglycerides & converts them into Free Fatty Acids (FFA) & Glycerol. Erepsin from intestinal juice converts simpler Peptides into Amino acids. Intestinal Lactase acts on Lactose & converts them into Glucose, Maltase converts Maltose to Glucose. Intestine Lipase converts fats into Fatty acids.
All above said enzymes, all other digestive enzymes & gastrointestinal hormones CCK, Secretin & Gastrin can be considered as objective representative of Agni mentioned by ayurveda. Jatharagni is exists from mouth to large intestine in the form of energy for all sorts of digestive conversions.
Awasthapak &functions of bhutagni ----
Ayurveda has mentioned 3 phases of primary digestion which are called Awasthapak. In the first phase i.e. Madhur awasthapak, mainly digestion of substance with madhur taste take place. Composition of madhur or sweet rasa is pruthvi (earth) + jala (water) mahabhut. Conversion of pruthvi & jala molecules will take place due to parthivagni & jalagni.
In second phase i.e. Amla awasthapak amla i.e. sour taste substances are disintegrated. Tejasagni disintegrates tej predominant molecules from food.
In the third phase of digestion i.e. Katu awasthapak, vaywagni & akashagni disintegrates vayu & akash predominant molecules from the food.
Above 3 phases take place at mouth, stomach, small intestine, large intestine. In these 3 phases, predominantly disintegration of panchabhutik elements takes place. Bhutikagni’s are responsible for this conversion or disintegration. So bhutikagni at primary digestion can be considered as a part of jatharagni.
After sara – kitta vibhajana i.e. separation of nutrients & waste part,ahara rasa or nutrient fluid is circulated in the whole body & then sukshma pachan or tissue metabolism starts.
From rasa to shukra, 7 dhatu’s are formed in their respective places or strotasas.
Role of bhutagni in shukshma pachan ----
To understand this concept, let us again understand modern physiology aspects. Proteins are converted into amino acids in primary digestion. Amino acids are absorbed from villi & through the blood circulation they reach to liver. Now again amino acids synthesize different proteins molecules like hemoglobin in the blood & myoglobin in muscles. This type of conversion is done by bhutagni again.
Similarly we can explain it in ayurvedic language. In sukshma pachana mamsa (muscles), meda (fats) these parthiv elements are formed. But parthivagni of mamsa & meda is different. This different type of conversion is possible only because of action of bhutagni’s during sukshma pachana.
Another example is apya or watery element. Jala or water is present in rasa dhatu, mutra or urine & in saliva as well. But again difference in jaliya quality is because of action of apyagni in sukshma pachana.
Action of Dhatwagni –
After seeing the role of bhutagni in sukahma pachana, some may get confused that what is the role of dhatwagni then?
Apyagni can provide water element to rasa dhatu. But rasa dhatu is also panchabhutik, so there are also other elements or molecules are present in rasa dhatu. Here, comes the role of dhatwagni, rasagni will form the total structure & composition of rasa dhatu as whole. Naturally dhatwagni’s role will be wider than the role of bhutagni.
Dhatu poshan nyaya (Theory about tissue metabolism) –
Ayurveda explains 3 important factors with relation to tissue metabolism as follows –
1) Kedar kulya nayay (Theory) –
This theory explains that specific places, channels i.e. strotasa’s are essential to get proper nutrition to the tissue. If channels are blocked, transport of nutrients & waste products will be hampered. This can damage to the tissue structure & quality. Practical example is myocardial infarction, due to coronary blockage.
2) Kshirdadhi nayay (Theory) –
Lot of conversions or transformations process take place when milk products are formed from milk. Milk is fermented & curd is formed. Curd is churned & butter milk is formed. After cooking the butter we get ghee. In the human body also lots of conversion & transformation process take place due to various enzymes & hormones. Proteins form pulses, are acted upon by enzymes & then muscle proteins are formed. In formation of any tissue, conversion & transformation process is very important. This can be explained by kshirdadhi nayay or theory.
3) Khale kapot nayay (Theory) –
Pigeon like birds has an ability to select the food grains from the dust & sand. Similarly in the human body each tissue & dhatu, select its own nutrients necessary for its growth or anabolism. For example, from the circulating blood, reticuloendothelium system will accept iron necessary for the formation of rakta dhatu or blood. Asthi dhatu or bone will select only calcium molecule for its anabolism. This theory explains selectivity action of body tissues during growth or anabolism.
In the present article, attempt is made to clarify Ayurvedic views about Agni’s & Pachana in scientific manner.
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