Opinion: Scientific Aspects of Tridosha – A Modern View – Dr. Nishant Barapatre and Dr. Mohan Tambe

Dr. Nishant Barapatre * and Dr. Mohan Tambe **

*Lecturer, Govt. Ayurved College, Bhavnagar, **Retd. Prof. Aryangla Ayurved College, Satara

  In the previous “Opinion-Based Article” titled, “Can Ayurveda – The Observational Science embrace Modernity?” – We had discussed the “Conundrum of Modernity for Ayurveda”. It was conferred that, a transition of an “Observational Science” of “Ayurveda” is a must, on the parallel lines of Modern Sciences, and not in terms of a “Philosophical Science”. For this purpose, it’s important to first discuss the scientific considerations of basic concepts of Ayurveda from a modern viewpoint, taking the recent scientific advances into consideration. As a first step in this direction, the scientific aspects of Tridosha i.e. Vaata, Pitta and Kapha have been discussed in this Article, predominantly based upon the logical thinking of Charaka Samhita, which has explained the concept of “Tridosha” in a more scientific way than any other texts.

HOW AYURVEDA CONSIDERS THE HUMAN BODY & ITS ACTIVITIES/ FUNCTIONS IN A SCIENTIFIC WAY? –
The basic principle, which governs the human body and is acceptable to Ayurveda as well as the Modern Medical Sciences, is the “Principle of Equilibrium (Homeostasis)”. The Modern Medical Science believes that, the body tries to remain in a relatively constant state. Later, it was revealed that this Equilibrium isn’t a static condition, but a dynamic one. Therefore, a new term “Homeodynamics” was coined later. The foundation of Ayurveda is also based upon the “Principle of Equilibrium (Homeostasis/Homeodynamics)”. However, the basic units which remain in Homeodynamics differ from each other in these two sciences. The Modern Medical Science considers the Equilibrium of Fluid levels, Water balance, Electrolytes and Buffer balance, Acid-Base equilibrium, Hormonal (Endocrine) balance, Sympathetic-Parasympathetic balance, O 2 -CO 2 balance etc.; while Ayurveda proposes the theory of Equilibrium of Dosha (Body Humors) – Dhatu (Body Tissues) – Mala (Excretory Products) as well as Manas Guna i.e. Satva-Raja-Tama.

Out of these, the Principle of “Tridosha” i.e. Vaata, Pitta and Kapha is a basic way of thinking about the human body in Ayurveda, on the basis of Observations as well as the Logical thinking. It is a theoretical framework, on the basis of which, the body physiology is understood practically. Therefore, they generally don’t represent separately distinguishable units in the human body, but are used in Ayurveda as “Templates” to construct different physiological mechanisms and interrelations in the human body. 1
For a better understanding of these “Templates” of “Tridosha”, let’s first look at the “Human
Body Cycle” as considered in the Ayurvedic science.

THE HUMAN BODY CYCLE AS PER THE CONSIDERATION OF AYURVEDA –
The “Textbook of Medical Physiology” by Guyton & Hall mentions that, the maintenance of a relatively constant volume and a stable composition of the body fluids are essential for homeostasis. The relative constancy of the body fluids is remarkable, because there is continuous exchange of fluid and solutes with the external environment as well as within the different compartments of the body. For example, there is a highly variable fluid intake that must be carefully matched by equal output from the body to prevent body fluid volumes from increasing or decreasing. 2
As Guyton & Hall have considered the exchange of fluid and solutes between the human body (Internal Environment) and the External Environment, we can observe the similar kind of exchange of Solids (Ex.- Food material), Liquids (Ex.- Water) or Gases (Ex.- O 2 and CO 2 ) between these two entities; as the human body (Internal Environment) is always surrounded by the External Environment and there’s a constant process of exchange going on between these two entities.

Figure 1 – Human Body Cycle

As Ayurveda is an “Observational Science”, it grossly observes the human body activities as they occur and propose a “Physiological Theory” based upon these observations. As depicted in the above “Figure 1”, Ayurveda observes the “Cycle of Human Body Functions” as an exchange between the External Environment (The Universe) and the Internal Environment (The Human Body). It may be the exchange of Food, Water, Oxygen or any other nutrient for that matter. However, the flow of this “Cycle” always remains the same i.e. from External Environment of the Universe to the Internal Environment of the Human Body, and back to the External Environment in a similar form or other. The performance of this Work i.e. this “Cycle” in the Human Body always occurs at the expense of Energy. Mainly two major types of Energy forms are involved in the performance of this Work viz.
Kinetic Energy responsible for all kinds of movements in the body and Thermal Energy responsible for any process of biochemical conversion occurring in the body. These two types of Energies are equivalent to Vaata Dosha and Pitta Dosha respectively in the human body, as per the Physiological consideration of Ayurveda.

However, the performance of all this Work can take place through some media only and this
media is provided by the major body fluids. Therefore, this liquid media possesses the same importance as that of the two types of Energies and hence, Ayurveda recognizes it as Kapha Dosha.

(A) VAATA DOSHA (~KINETIC ENERGY) –
It is the consideration of each and every movement in the body, be it regarding the “movement of smallest particles” like electrons or the “movement of gross substances” like the fecal matter. We can functionally observe these movements in the human body, but can’t directly observe the Kinetic Energy responsible for these movements. Therefore, Vaata Dosha has been described in Ayurveda as “Avyakto Vyaktakarma cha” i.e. which doesn’t appear physically, but expresses itself by its actions. There are various activities occurring in the human body, which can scientifically be observed today through the modern technological advances; like – Cell division and multiplication, Differentiation
of embryonic layers and the development of organs, Streaming of Protoplasm in a Cell, Osmotic movements through Semipermeable cell membrane, Muscle contractions & relaxations as a part of motor functions, Conduction of nerve impulses, Rhythmic movements like Respiration and Circulation, Excretory function, Swimming movements of Spermatozoa etc. 3 However, due to the lack of such technologies at that times, such minute understanding of various physiological activities wasn’t possible and therefore, all such kinetic activities in the body were attributed to a common entity under the nomenclature of “Vaata Dosha”.
Though Kinetic Energy is a scalar quantity, which does not have a direction; but the motion
produced will always have a linear or rotational direction. As Kinetic Energy is the energy of mass in motion, the five types of Vaata Dosha (Pancha Vaayu) can be correlated according to the directions of their motion.
(1) PRAANA VAAYU – Any movement in the body, from external environment to the Human Body (Internal environment) can be correlated to Praana Vaayu. In simple words, anything that enters inside the body through its natural route of entry, can be said to be driven by Praana Vaayu. For example – Inspiration of O 2 , Deglutition of food and water, etc.
(2) UDAANA VAAYU – A movement in the reverse direction of Praana Vaayu, i.e. from Human Body (Internal Environment) to External Environment, through the external orifices of upper parts of body; can be correlated to Udaana Vaayu. For example – Expiration of CO 2 , Vocalization etc.
(3) APAANA VAAYU – A similar kind of movement in the reverse direction of Praana Vaayu, from Human Body (Internal Environment) to External Environment, but from the external orifices of lower parts of body; can be correlated to Apaana Vaayu. For example – Excretion of Urine, Feces; Seminal ejaculation, Menstrual flow, Delivery of the fetus etc.
(4) VYAANA VAAYU – All the internal movements of the body, in a direction from the centre to the periphery (As a Centrifugal Force), can be correlated to Vyaana Vaayu. For example – Internal circulation of fluids like Blood circulation, from the heart to the peripheral cells of the body.
(5) SAMAANA VAAYU – The internal movements in the body, from the peripheral tissues to the central part, in the form of Centripetal Force, can be correlated to Samaana Vaayu. It has been labeled as “Agni Sameepastha” i.e. it resides near the Agni and helps in digestion. For example – The secretion of Gastric Juice into the stomach, Flow of Bile Juice and Pancreatic Juice into the Duodenum, etc.
Though above-said is a common correlation of Samaana Vaayu with respect to Acharya
Vagbhata, Acharya Charaka has opined in a different manner. As per Charaka Samhita, Samaana Vaayu is “Sveda Dosha Ambu Vaahini Strotamsi Samadhishthita” i.e. it functions all over the body for “Equal (Samaana) distribution” of the nutrients through general circulation to the body cells according to their need. As these distributed nutrients further undergo “Energy metabolism” (Function of Agni) inside the cells, it has been said to be “Antaragne Parshvastha” (Located beside the cellular Agni). Moreover, this Samaana Vaayu distributes the nutrients to each and every cell in the body for energy metabolism; and therefore, it has been described as “Agni Balaprada” (Provides strength to the cellular Agni) 4. Thus, Samaana Vaayu can be correlated to the movement of nutrients from the peripheral blood circulation towards the cell (Centripetal Force), considering the cell as a
center.

Figure 2 – Directions of 5 Types of Vaata Dosha

(B) PITTA DOSHA (~THERMAL ENERGY) –
It is the consideration of conversion of biochemical compounds like carbohydrates, proteins etc. with the help of Thermal Energy; and therefore, is equivalent to the concept of Agni (Thermodynamics) in Ayurveda. However, the requirement of Thermal Energy at different levels of conversion is variable. Hence, different thermal activities at different levels of biochemical conversion are classified as separate types of Agni (Thermodynamics) i.e. Jatharagni (Thermodynamics at Digestive Level), Dhatvagni (Thermodynamics at Tissue Level) and Bhutagni (Thermodynamics at Elemental Level) in Ayurveda. The Gastric Juice containing pepsin, rennin, lipase etc. can be said to be equivalent to Jatharagni; while intracellular enzymes for cellular digestion correspond to Dhatvagni and Bhutagni.

As this Thermal Energy (Agni in Ayurveda) is not expressed in the form of a “Flame”, it is not perceptible directly. Therefore, this thermal activity is observed in the form of biochemical conversions (Paaka), which occur through liquid media only. This chemo-thermal activity taking place in the liquid medium has been considered as Pitta Dosha in Ayurveda.
Therefore, various chemo-thermal activities occurring in the human body, which have now been established scientifically through modern sciences, can be correlated with the Pitta Dosha; like – All metabolic activities (Anabolism and Catabolism), Complete process of Digestion, Complete enzyme system, Hormonal basis/Endocrine system (Ex.- Insulin for carbohydrate metabolism), etc.
The five types of Pitta Dosha can be correlated with five major kinds of biochemical conversions occurring in the Human Body.

(1) PAACHAKA PITTA – The process of Digestion (i.e. biochemical conversion of large food substances into small water-soluble food molecules) takes place under the influence of Paachaka Pitta. Therefore, this Pitta corresponds to the Digestive secretions of Gastric Juice, Bile Juice and Pancreatic Juice (Digestive Enzymes), as well as the Digestive Hormones like Gastrin, Secretin etc.
(2) RANJAKA PITTA – The conversion of non-colored materials into colored materials, taking place in the human body, is the concept of Ranjaka Pitta in Ayurveda. For example – Hemoglobin synthesized during Erythropoeisis, which gives a characteristic red color to the Erythrocytes, can be compared to the Ranjaka Pitta. Also, the Castle’s intrinsic factor located in stomach and duodenum; which helps in cobalamin (Vitamin B 12 ) absorption from the intestine, ultimately leading to sufficient Red blood cells production; can be related to the Ranjaka Pitta in Ayurveda. 5 (3) AALOCHAKA PITTA – The external stimuli of light rays produce a photochemical reaction in the human eye, bringing about some changes in the Retina and generating an Optic impulse for the visual sensation. This complete process of conversion/interpretation of light rays corresponds to the activity of Aalochaka Pitta.
(4) BHRAAJAKA PITTA – The interpretation of tactile stimuli, through the sensory nerve endings present beneath the skin surface, can be correlated with Bhraajaka Pitta. Also, it can be further considered as the radiation of Thermal Energy from the skin, which can be perceived as Body temperature. Moreover, the surplus energy is sometimes radiated from the body and transmitted through the skin to the external environment. This is a special concept of “Aura”, which relates to the transmission of Thermal Energy (Bhraajaka Pitta) from the body to the surrounding environment through the skin.
(5) SAADHAKA PITTA – It is considered to be situated in “Hridaya” (Heart) as per Ayurveda. However, it should be functionally related to the “Central governing system of the Body and Mind” (consisting Shadanga i.e. all major body systems, including the Central Nervous System) in a wider sense 6, and not limited to the four-chambered Heart; thus relating to its functions like Buddhi (Intellect), Medha (Power of retention of knowledge), Dhriti (Fortitude), Smriti (Memory), Viveka (Discriminating power) etc.

According to Vaidya Ranjit Rai Desai – The hormone “Adrenaline” secreted by Adrenal medulla (under the control of Sympathetic nervous system through Splanchnic nerves) influences the action of Heart in conditions like fear, panic, courage, anxiety, tension, excitement etc. Though it’s not secreted by Heart itself, but has specific action on the Heart; therefore, it can be considered as “Saadhaka Pitta” as mentioned in Ayurveda. 7 Thus, various Neurohormonal pathways can be correlated with the activities of Saadhaka Pitta.

(C) KAPHA DOSHA (~BODY FLUIDS) –
The body fluids provide a transaction media for the transport of all kinds of nutrients, originating from the consumed food, right up to the cellular level. Therefore, all these body fluids like Circulatory fluid, Interstitial fluid, Intracellular fluid etc. can be considered as Kapha Dosha in Ayurveda. Apart from being a fluid medium for transportation, these body fluids also perform some other functions related to their physical structure, as Kapha Dosha is the only gross entity having mass & volume amongst Tridosha. Therefore, it confers some physically attainable activities like – Growth and Nourishment, Adhesion/Cohesion (Ex.- Fusion of Ovum and Sperm), Lubrication and softening, All reparative activities (Ex.- Healing, Proliferation) etc.
Although we can use the term “Kapha Dosha” for the whole “Fluid matrix” in human body; still, the body fluids are sub-divided into five types of Kapha Dosha from an Ayurvedic perspective, depending upon their utility; just like the division of Tap water at households, like Drinking water, Cooking water, Washing water etc.

(1) KLEDAKA KAPHA – Like the Cooking water used at the households, the body fluids utilized for preparing a suspension of consumed food inside the stomach, can be considered as Kledaka Kapha in Ayurveda. Therefore, the production of Saliva in the oral cavity and other secretions from Gastric mucous glands like Mucin; which make the food soft, moist, unctuous and disintegrate it; can be correlated with the Kledaka Kapha. 8
(2) BODHAKA KAPHA – The body fluids, which make “Avabodha” (Knowledge) of the external substances to the human body through oral consumption, can functionally be called as Bodhaka Kapha. The modern sciences have confirmed that, any substance should first be dissolved in a liquid media as a solution; then only its taste can be perceived. Therefore, the serous and/or mucus salivary juices; secreted by sublingual, submaxillary, submandibular and parotid salivary glands; represent the Bodhaka Kapha of Ayurveda.
(3) SHLESHAKA KAPHA – The meaning of “Shleshana” is “To connect” or “To attach”. Therefore, “Shleshaka Kapha” can be correlated to the body fluids, which help in cohesion of any two or more structures in the human body. For example – The Synovial fluid binding the bony ends in the joints, the intercellular cementing substances like Cholesterol sulfate, Ceramides etc.
(4) TARPAKA KAPHA – The word “Tarpana” means “To nourish” or “To refresh”. Hence, “Tarpaka Kapha” can be considered as the body fluids in the head region, which bring about “Shirastha Indriya Tarpana” i.e. nourishment of all Sense Organs as well as the Control centers of Sensory Perception present in the brain. In this context, the Endolymph & Perilymph present in internal ear, the Aqueous & Vitreous humors present in the eyeball, as well as the CSF (Cerebrospinal fluid) circulating through meninges and ventricles of brain can be correlated to the “Tarpaka Kapha”. 9

(5) AVALAMBAKA KAPHA – “Avalambana” means the dependency of the life processes. In Ayurveda, the location of Avalambaka Kapha is considered to be “Hridaya” (Heart) and its main functions are described to be “Trika Sandhaarana” (Protection of triangular area between neck, shoulders & heart) and “Hridaya Avalambana” (Supporting the vitality of heart & enable its normal function). As the vital organs in this “Trika” area (Lungs & Heart) are supported and protected by Pleural fluid, Pulmonary surfactant in the alveoli & Mucin in the Bronchi (in the case of Lungs) and Pericardial fluid & Coronary blood circulation (in the case of Heart); all these body fluids can be anatomically
correlated to the Avalambaka Kapha in Ayurveda. 10
However, as we have already considered the “Hridaya” (Heart) functionally related to the
“Central governing system of the Body” (extended all over the body) in a wider sense; therefore, the functions of Avalambaka Kapha can also be generalized throughout the body. Since maintaining theequilibrium of body fluids (~Kapha) is an important aspect for avoiding the pathologies like edema, the “Trika Sandhaarana” can also be considered as “maintaining the equilibrium between the three compartments of body fluids viz. Intracellular Fluid (ICF), Extracellular Fluid (ECF) and Circulatory Fluid”. Though it may appear as a solitary opinion by the authors; still it’s worth a thought on the basis of logical thinking.

CONSIDERATION OF TRIDOSHA AS PER BASIC SCIENCES –
In this way, Ayurveda – being an Observational Science – has first observed the physiological activities (Effect or Work) taking place in the human body and later contemplated upon the Cause (Energy) behind this Effect (Work). Using this methodology to understand the Cause and Effect Relationship (Kaarya Kaarana Bhaava), Ayurveda has concluded that – there are three major functions in the body and their three basic causes are “Tridosha” (Three body humors).

Out of these, two Dosha (Body humors) are related to the liquid media viz. the body fluids as Kapha Dosha and the chemo-thermal liquid medium for biochemical conversions (Paaka) as Pitta Dosha. The remaining one i.e. Vaata Dosha is the Energy, effecting all kinds of movements in the body and therefore, this directional force can be considered as “Vector” and later can be subdivided according to its direction (The five subtypes of Vaata Dosha).

Vaata Dosha, being Energy or a Force, can only be observed through its effects, in the terms of movements. Therefore, it’s an entity which can be understood with the help of Physics. On the other hand, Pitta Dosha can be understood with the concepts of Biochemistry and Kapha Dosha can be understood in terms of human body activities with the help of Biology. Therefore, to facilitate the understanding of these basic entities of “Tridosha” in Ayurveda, it can be modernized by correlating with the concepts of basic sciences like Physics, Chemistry and Biology respectively.

CONSIDERATION OF TRIDOSHA AS PER BIOMEDICAL SCIENCES –
With respect to the Biomedical sciences, the concept of Tridosha is comparable to the scientific field of Neuro-Endocrine-Immunology (N.E.I.), under which the links of bidirectional communications between Nervous system, Endocrine system and Immune system are investigated, to explore its correlation with physical health. 11

These three systems function unanimously in order to preserve the homeostasis in the body. The Nervous system and Endocrine system regulate the effects of various stressors on the body (Internal stressors like metabolic, osmotic or reproductive stressors; as well as the External stressors), and the Immune system works to either eliminate or control the foreign invasion in the body. Though these systems might appear to be working independently, they actually function in an integrative manner through bidirectional communication for maintaining the homeostasis and immune balance.
For example, any systemic infection and its attendant stress on the body is regulated and
controlled through the bidirectional communication between the Neuroendocrine systems and the Immune system.The Immune system releases cytokines due to this septic stress, which in turn results in secretion of neurotransmitters and hormones by the Nervous system and Neuroendocrine system respectively. All these factors are collectively responsible for the generation of Immune response as well as Stress response, to encounter this septic stress; and also cause the down-regulation of both these responses, on eradication of the infection. In this way, the coordination of “Neuroendocrine systems
and the Immune system”and the bidirectional communication between them regulate the human body responses and maintain the homeostasis. 12

Thus, in Neuro-Endocrine-Immunology (N.E.I.), the functions of Nervous system can be
correlated with the functions of “Vaata Dosha”, Endocrine system with that of “Pitta Dosha” and Immune system with “Kapha Dosha”. Therefore, it can be said that “Neuro-Endocrine-Immunology” is a modern approach of Biomedical sciences to understand the body physiology and “Tridosha Siddhanta” is the peculiar perception of Ayurvedic system regarding the same body physiology in a different manner with different terms.