Rasa dhatu
The word ‘rasa dhatu’ literally means the component of body with nutrients and essence. There are two forms of rasa related to body physiology. Ahara rasa is the essence of food after the first level of digestion by jatharagni (factors responsible for digestion and metabolism) in the stomach. The second form is rasa dhatu. It is the component formed after the ahara rasa gets acted upon by rasa dhatvagni.
Etymology and derivation:
The word ‘rasa’ is derived from the Sanskrit root “ras” having the meaning of taste, to relish, to perceive, to feel, to desire.[1]
Rasa is derived from the root ‘gatau’ which means moving. As the nutrient fluid is continuously circulated in our body, it is known as rasa.[Su. Sa. Sutra Sthana 14/13]
Synonyms:
• Adyadhatu(first dhatu) [Ash. Hr. Sutra Sthana 13/25]
• Aharaparinama dhatu (transformed from food) [Cha. Sa. Nidana Sthana 1/23]
• Prasada and sara are the synonyms of rasa in the context of ahararasa.
Meanings in different contexts:
The word rasa has a wide range of meanings like taste, extract/juice, meat soup, mercury.
In context of body components, the terms like ahararasa, rasa dhatu and sharirarasa/garbharasa are described.
The word ‘garbharasa’ is applied to denote ojas (essence or vitality) in embryonic life. This is transformed into unctuous body fluids. [Cha. Sa. Sutra Sthana 30/10]. It is known as ‘sharira rasa’ in later life leading to formation of ojas. [Cha. Sa. Sutra Sthana 30/11].
Panchabhautika constitution and properties:
The rasa dhatu has jala mahabhuta predominance in its constitution. It possesses drava (liquidity), sara (fluidity), manda(opaque), snigdha(viscous) and pichchila(unctuous) properties.[2]
Formation and metabolism of rasa dhatu
Rasa dhatu is formed from ahara rasa (essence of food). The ingested food is disintegrated into two parts: prasada (essence or useful part) and kitta (waste). The prasada is called ahara rasa (essence of food). This essence is transformed into a nutrient fluid called ‘rasa dhatu’. [Cha. Sa. Sutra Sthana 28/4]. It is the ultrafine form of ahara rasa. [Su. Sa. Sutra Sthana 14/3]
The rasa dhatu is further acted upon by rasa dhatvagni. It is divided into two portions. The first portion forms sthayi rasa dhatu(permanent form) for carrying out physiological functions of nourishment and maintenance of body.
The second portion called ‘poshaka rasa’ is carried forward to nourish the next ''dhatu'' i.e.''rakta''. [Cha.Sa. Chikitsa Sthana 15/16]
During the metabolic process, this rasa is transformed into ''rakta dhatu'' by action of ranjaka pitta. It acquires a red colour during this process. This metabolism takes place at yakrit (liver) and pliha(spleen). [Su. Sa. Sutra Sthana 14/4]
Upadhatu and mala (metabolic byproducts and waste products):
Stanya (breast milk) and artava(menstrual blood including ovum) are formed as upadhatu (metabolic byproducts) of rasa dhatu.[Cha. Sa.Chikitsa Sthana 15/17]. Sharangadhara considers only stanya(breast milk) formed as upadhatu. [Sharangadhara Sam. Purvakhanda chapter 5].
Various secretions and discharges are formed in this process as ‘kapha’. This is termed as "malarupakapha".
Quantity of rasa dhatu in body:
The total quantity of rasa is nine anjali. One anjali is equal to the quantity that can be filled in a space formed from joining one’s palms together. This measurement is person-specific. [Cha. Sam. Sharira Sthana 8/15]
Time span:
The rasa dhatu is formed in a time span of 3015 kala (five days). [Su. Sa. Sutra Sthana 14/14].
Circulation of rasa dhatu
The rasa dhatu is circulated through twenty-four dhamani (vessels) originating in the cardiac region. The upper and lower part of body is nourished by ten vessels each. The remaining four nourish lateral parts of body. [Su. Sa. Sutra Sthana 14/3] All the twenty-four vessels are described in a separate chapter named ‘dhamanivyakarana sharira.[Su.Sa.Sharira Sthana 9] Vyana vayu carries out the circulation of rasa dhatu. [Cha.Sa.Chikitsa Sthana 15/36]
Rasavahi/ Rasaharini:
Heart of the fetus is linked to the mother’s heart through the rasavahi (the channels carrying nutrients.) The fetus expresses its wishes to the mother through these channels. [Cha. Sa. Sharira Sthana 3/15].
During the eighth month of gestation, the ojas(vital essence) is unstable. It moves from mother to fetus and from fetus to mother through these channels.[Cha. Sa. Sharira Sthana 3/24].
Rasavaha srotas:
Rasavaha srotas is the transport system of circulating rasa all over the body. It originates from the heart and circulates rasa through ten vessels. [Cha. Sa. Vimana Sthana 5/8] The same organs and channels form pranavaha srotas. [Su. Sa. Sharira Sthana 9/12]. This means the heart and channels transporting rasa also carry prana (vital force) in the body.
Role of rasa dhatu in embryogenesis:
During embryonic life, rasa dhatu is the only source of nutrition. The heart of the fetus is connected with the mother through the placenta and umbilical cord. The fetus gets rasa dhatu (nutrient fluid) through this placental circulation. Growth and development depend upon nutrition provided by rasa dhatu. This promotes strength and complexion of the fetus as it is composed of materials having all six tastes. This rasa also nourishes the mother’s body and carries out lactation.[Cha. Sa. Sharira Sthana 6/23]
Rasa is also one among six sources of origin of fetus along with maternal and paternal factors. During embryogenesis, it is responsible for the formation and growth of body parts, sustenance of life, satiety, nourishment and enthusiasm. [Cha. Sa. Sharira Sthana 3/12]
Functions of rasa dhatu:
The functions attributed to rasa dhatu are:
• Tarpana: nourishment of body at any age.
• Vardhana: growth and development (especially in kids)
• Dharana / jeevana: stabilizing and maintaining the ''dhatu'' (during middle age)
• Yapana: preventing the total deterioration of ''dhatu'' (during old age)
Other functions like avashtambhana(stabilizing the body components), snehana(unction) are also carried by rasa dhatu[Su. Sa. Sutra Sthana 14/3]
It is responsible for tushti(satiety), preenana(nurturing body), raktapushti(nourishing ''rakta dhatu'').[Su. Sa. Sutra Sthana 15/5]
Importance in diagnosis:
Causes of vitiation
Excess consumption of heavy to digest, cold, over-unctuous food, overeating and excessive mental stress cause vitiation of rasavaha srotas. [Cha. Sa. Vimana Sthana 5/13]
Abnormal states
The increase or decrease in quality and/or quantity of rasa dhatu can lead to various abnormal conditions. The states can be assessed by following clinical features.
| Symptoms of rasa kshaya(decrease of rasa dhatu)* | Symptoms of rasa vriddhi (increase in rasa dhatu)** |
|---|---|
| Dhatu apachaya/ksheenata(degeneration/depletion of other ''dhatu'') | Agnimandya(diminished digestive power) |
| Mukhashosha/rukshata(dryness of mouth) | Utkleshana(nausea) |
| Sharirashosha/rukshata(dryness or depletion of body mass) | Praseka(salivation) |
| Karshya (emaciation) | Chchardi(vomiting) |
| Trishna(thirst) | Alasya(lack of enthusiasm to do work) |
| Shunyata(feeling of emptiness) | Gaurava(heaviness in body) |
| Shrama(tiredness) | Shvaitya(whitish discoloration of body) |
| Shabdaasahishnuta (intolerance to sound) | Shaitya(feeling of abnormal coldness of body) |
| Hrudayaghattana(pain in the heart with a feeling that someone is holding and vigorously shaking the heart) | Angashaithilya(looseness in body parts) |
| Hrutkampa(trembling sensation of heart or tachycardia) | Shwasa(dyspnoea) |
| Hrutdrava(palpitation) | Kasa(cough) |
| Hrutshola(cardiac pain) | Atinidrata(excessive sleep) |
| Shrama/klama (fatigue or tiredness even after doing a small work) | -- |
- *[Cha. Sa. Sutra Sthana 27/764], [Su. Sa. Sutra Sthana 15/9], [A. Hr. Sutra Sthana 11/17]
- ** [Su. Sa. Sutra Sthana 15/14], [A. Hr. Sutra Sthana 11/7-8]
Clinical features of vitiation of rasavaha srotas:
If the transport channels of rasa dhatu are vitiated, then following clinical features are observed:
• Aversion towards food, anorexia, altered sense of taste, inability to identify tastes, nausea, heaviness in the body, drowsiness, body ache, fever, blackouts, anemia, obstruction of channels, impotence, tiredness (angavasada), emaciation, diminished ''agni'', and premature aging (wrinkling of skin and graying of hair [Cha. Sa. Sutra Sthana 28/9-11]
• In addition to the above features, the following features are observed after injury to rasavaha srotas: Shosha(emaciation),akroshana(crying due to pain), vinamana(bending),mohana(confusion),bhramana(vertigo), vepana(trembling)and death. [Su. Sa. Sharira Sthana 9/12]
Role of rasa dhatu as vitiated factor in disease:
Rasa dhatu is involved in the pathogenesis of many diseases like jwara [Cha. Sa. NidanaSthana 1/20], prameha(obstinate urinary diseases including diabetes) [Cha. Sa. Nidana Sthana 4/7] and shosha(emaciation including tuberculosis) [Cha. Sa. Nidana Sthana 5/8].
The extremes of body frames i.e. sthaulya(obesity) and karshya(emaciation) depend on the quantity and quality of rasa dhatu, its distribution, conversion, and utilization in the body [Su. Sa. Sutra Sthana 15/32]. These two conditions are risk factors for a wide range of metabolic disorders and lifestyle disorders.
Importance of concept in preservation of health and prevention:
The existence of ''purusha'' depends upon rasa. Therefore, one should protect and maintain the quality and quantity of rasa dhatu with utmost care.[Su. Sam. Sutra Sthana 14/12] It can be achieved through proper diet and lifestyle.
Rasayana (rejuvenating therapy) is a special branch of Ayurveda dealing with the promotion and preservation of health. It helps in maintaining the best qualities of rasa dhatu and other body components. The quality of rasa is directly responsible for the quality of other tissues, immunity, promoting health and longevity. [Su. Sa. Chikitsa Sthana 27/1,Dalhana]
Management of diseases:
Conditions including increase in rasa dhatu:
Langhana (fasting and other reduction therapies) is the principle of treatment for the disorders due to vitiation of rasa dhatu. [Cha. Sa. Sutra Sthana 28/25]
It is also indicated in jwara. [Cha. Sa. Chikitsa Sthana 3/142] In the context of dhatugata jwara, for the management of rasadhatugata jwara, vamana(therapeutic emesis) and upavasa(fasting) are mentioned as the treatment choices. [Cha. Sa. Chikitsa Sthana 3/315]
Conditions including decrease in rasa dhatu:
In the conditions like rajayakshma or shosha (emaciation including tuberculosis), tarpana (nourishment therapy) is indicated. The treatment regimen includes variety of meat soups and juices. [Cha.Sa.Chikitsa Sthana 8/149-172]
Current researches:
In view of modern physiology, the rasa dhatu includes plasma, interstitial fluids and lymph. The rasa dhatvagni is related with glucose metabolism, circulation in portal vein, formation of white blood cells. In opinion of some researchers, rasa dhatu has three major components solids, water and gases. Solids are 7-8 % and contains organic substances like plasmaproteins, carbohydrate, enzymes, nonprotein nitrogenous substances, amino acids, internal secretions like hormones and antibodies.Inorganic substances include sodium, calcium, potassium, magnesium, bicarbonate, chloride, phosphate, iodide, iron and copper. Water is 92-93 %. The gases include oxygen, carbon dioxide and nitrogen. As per the opinion of Singh G., the fluid flowing in blood vessels is a mixture of ahararasa, rasa, shonita etc.It is not one dhatu.From modern physiological point of view also, the liquid flowing in the blood vessels is a mixture of nutrients, plasma, red blood cells, white blood cells, platelets etc. Some researchers opine that the clinical conditions of increase in rasa dhatu can be considered as acidosis or hypercalcaemia or chronic liver diseases. Whereas the conditions of decrease in rasa dhatu corelates with alkalosis or hypokalaemia or hypocalcaemia or hyponatremia or hypomagnesemia.
List of theses done
1.Vaidya M.D.(1963): Rasavaha Srotasa Pareeksha, Dept of Kayachikitsa, IPGT &RA, Jamnagar
2.Mishra R. K. (1967): Physio-pathological approach on the concept of Rasa- KshayaandRasa- Vriddhi. Dept of Kayachikitsa, IPGT &RA, Jamnagar
3.Pandey H. N. (1987): Rasavaha Sroto-Dushti Ka Naidanika Adhyayana Hrid- Rogon Ke Pariprekshya Mein. Dept of Kayachikitsa, NIA Jaipur.
4.Kulkarni S.(1994): A study on the concept of Stroto-Dushti w.s.r. to Rasavaha Srotasa, Dept of Basic Principles, IPGT &RA, Jamnagar.
5. Kumara J. M. W.S.(1996): A comprehensive study of Rasavaha Srotasa w.s.r. to Shotha, Dept of Basic Principles, IPGT &RA, Jamnagar.
6.Rakesh M. Changani(2018): Fundamental And Applied Study of Rasapradoshaja Vikara And Its Principle of Management w.s.r. to Aruchi, Dept of Basic Principles, IPGT &RA, Jamnagar.
7. Bharat L. Bhadiyadra(2018): A study on Rasavaha Sroto Dushti in context to Karshya.(Ph.D.), Dept of Basic Principles, IPGT &RA, Jamnagar.
8. Priya Gupta(2019): A study on Hetuskandha in context to Rasavaha Srotas through the Experimental & Survey Study, Dept of Basic Principles, IPGT & RA, Jamnagar.