THE JOURNAL OF ALTERNATIVE AND COMPLEMENTARY MEDICINE
Volume 7, Number 5, 2001, pp. 567–574
Mary Ann Liebert, Inc.
Ayurvedic Physiology and Etiology: Ayurvedo
Amritanaam. The Doshas and Their Functioning in Terms
of Contemporary Biology and Physical Chemistry
ALEX HANKEY, Ph.D.
The three doshas of Ayurveda and their five respective subdoshas are related to the modern scientific framework of systems theory, phase transitions, and irreversible thermodynamics. These
empirically well-established concepts of Ayurveda then appear to be far more general biologic
concepts than the neuroendocrinology of their functioning might imply. They express universal
concepts applicable across living organisms—control structures governing living systems. The
hypothesis that the 15 subdoshas can themselves be considered as 5 triplets implies that on the
level of the whole organism, these secondary structures of control appeared at specific stages in
the evolution of life, yielding new insights into their development and evolution. The description of varying states of health and disease given in Ayurvedic etiology is related to the format
of phase transitions in irreversible thermodynamics.
yurveda is well known as the Vedic system of health care of India, practiced effectively for thousands of years by millions of
people (Sharma, 1981–1996; Bhishagratna 1991
and 1996; Murthy, 1984, 1986, 1991 and 1992,
1998 and 2000; Sharma and Clark, 1998). Yet
the terms and concepts it uses to describe types
and functioning of the human body, to classify
levels of health, and to describe the onset of disease have not yet been related to modern scientific biology and medicine. Despite its success, Ayurveda appears unscientific to the
scientist, and for that reason has attracted crit-
icism (The Lord Walton, 2000; U.K. Department
of Health, 2001; Hansard, 2001).
The purpose of this paper is to outline possible ways in which certain concepts in
Ayurveda can be related to those in modern biologic sciences. In this way, the substance of
Ayurvedic theory may become better understood. Furthermore, there is the resultant potential for related research into the nature of life
and living systems.
Linguistically, Ayurveda is the union of the
two words “Ayus,” meaning lifespan of anything in creation from the smallest subatomic
particle to the whole universe, and “Veda,”
meaning knowledge in the pure sense of the
Maharishi Foundation, London, United Kingdom.
term. Ayurveda thus literally means the science
of the lifespan of all things in creation, including how such lifespans may be related to each
other. One verse from the primary text on
Ayurveda, the Caraka Samhita (Sharma,
1981–1996), states “Ayurvedo Amritanaam,” that
the purpose of Ayurveda is to gain immortality—the longest lifespan of all.
The image of life as a river—an endless
stream of processes that produce continuous
change, yet enable the overall form to remain
the same—is consistent with the viewpoint
of Ayurveda. Every day we breathe, eat and
drink, and process large quantities of various
kinds of matter, yet we may remain relatively
unchanged. By understanding how the different processes involved maintain the bodily system, we may gain insights into its various
modes of functioning. The river image is parallel to modern understandings of life based
on systems theory (e.g., Weinberg, 1975) and
nonequilibrium thermodynamics (Eigen and
Schuster, 1979; Prigogine, 1980), and points to
such areas of modern science as possible
sources of parallels to Ayurveda.
Most Western biomedical explanatory models of the body are framed in terms of biochemistry, rather than physics. In contrast,
most traditional medical systems such as
Ayurveda begin with “energy” for their theory
of biologic processes, so that in essence they begin with physics, and move on to explaining
biochemical and biologic levels on that basis.
This may explain the misunderstanding, and,
often, dismissal of such models found in modern Western medicine. It may also be in part
because of lack of appreciation of the true scientific nature (and basis) of these explanatory
models or paradigms. It is to be noted that the
relative lack of physics in modern medical explanatory models does not imply the absence
of laws of physics in bodily processes.
This paper attempts to begin a process of elucidating the fundamental Ayurvedic explanations of physiologic functioning in terms of
contemporary physics, physical chemistry, and
a systems approach to biology. From these perspectives, Ayurveda’s concepts make sense,
and provide a theoretical basis for linking biologic processes and outcomes across species.
Our paper may also provide a starting point
for bridging the conceptual divide between
Western and non-Western traditions—a divide
that has recently seen the dismissal of
Ayurveda and Traditional Chinese Medicine
by the House of Lords Committee on Complementary and Alternative Medicine (The Lord
Walton, 2000; U.K. Department of Health, 2001;
Hansard, 2001), because of a failure to appreciate the theoretical underpinnings of these systems.
THE DOSHAS AND THEIR SUBDOSHAS
Ayurveda states that the human body is governed by three doshas that play the role of regulatory factors governing the internal processes
by which it functions and is maintained
(Sharma, 1981–1996; Bhishagratna, 1991 and
1996; Murthy, 1984, 1986, 1991 and 1992, 1998
and 2000; Sharma and Clark, 1998). The three
doshas also govern more external processes
through which they interact with the outside
world. They are given the names vata, pitta, and
kapha. Each dosha is supplemented by five subdoshas regulating specific processes in different
parts of the body (see Tables 1 and 2).
Systems theory identifies three fundamental
processes requiring regulation present in any
system: input/output (transport), turnover,
and storage (Weinberg, 1975). This is as true for
any subsystem as it is for the overall system,
and indicates that regulatory control factors
should be present in triplets: one each for transport, turnover, and storage.
Systems theory thus requires the existence of
triplets of regulatory control factors for any living system: for the whole system and for each
of its major subsystems, such as the epiderm,
the digestive system, the central nervous system, and the circulatory system, of which the
major organs are the heart and lungs.
TABLE 1. PHYSIOLOGIC FUNCTIONS A SSIGNED
TO THE THREE DOSHAS
AYURVEDIC PHYSIOLOGY AND ETIOLOGY
TABLE 2. SOME MAJOR PHYSIOLO GIC FUNCTIONS
TABLE 3. ASSIGNMENT
From this perspective, and also using the
suggestion that the digestive tract of living organisms evolved in two distinct phases, first
the mouth and stomach, and then the lower digestive tract, it is possible to make the tentative
identifications of the three doshas and their five
respective subdoshas given in Table 3.
In this simple way, all the doshas and subdoshas can be related to the concepts of systems
theory and control theory based on the elementary correspondence: doshas constitute the
regulatory factors for a whole living system, while
subdoshas are the corresponding factors for its
The structure of Table 3 thus suggests that
the concept of doshas is fundamental to biology
and lends strength to the Ayurvedic perspective that all life and living systems may be considered in terms of them.
DOSHAS FOR A SINGLE CELL
It is pertinent to look at the case of the single cell, for this gives an indication of which
sectors of cellular metabolism are governed by
the different doshas. Vata, governing input/output, would clearly be responsible for active
PHYSIO LOGIC SYSTEMS
a Here Digestive tracts I and II do not refer to regions of the human digestive tract, but to its developmental stages
in multicellular organisms in biologic history. First, just a “mouth” and a ‘stomach” with taste, digestion, absorption,
and water regulation functions as indicated in I and then in, e.g., primitive worms, a true gut with peristaltic motion,
different regions for acid and enzyme production, absorption and elimination, additional functions are represented
here under II.
b Because certain doshas are involved in more than one subsystem, e.g., prana in taste in the mouth and also in swallowing, this correspondence is not exclusive. Table 3 is only meant to suggest which dosha function dominates each
subsystem at its earliest stage of development. For example, samana and kledaka are necessary after the development
of a gut but not for organisms possessing only a mouth, which only require the functions of apana and bhodaka. Similarly, the liver plays a vital role in blood purification as well as promoting digestion. The latter function is emphasised here for ranjaka. Because the liver’s enzymes take more time to act in the moving chyme, pachaka is taken as representative of the functioning of digestive tract I.
transport across the cell membranes, and, in
particular, for homeostasis, including such
things as the sodium/potassium balance, the
scavenging of particular ions and molecules,
the entry of food and other molecules into the
cell and the elimination of waste materials,
inasmuch as regulated active transport is required for the processes concerned. Governing
motion, it would also be responsible for mitosis (and meiosis).
Pitta, being responsible for metabolism, must
govern the Krebs cycle because this is the principal way food molecules are used to create energy-rich adenosine triphosphate (ATP) and
other high-energy molecules used for the synthesis of molecules needed in cell growth.
Taken together with transformation, this suggests that all the processes involved in ribosome-mediated enzyme synthesis are also the
domain of pitta.
Energy production and its regulation are of
central importance. Life continuously produces
entropy as its strategy of bypassing the second
law of thermodynamics. It creates and maintains order (or negative entropy), only as a
byproduct of its greater, overall entropy production. This is a first indication that the detailed thermodynamics of the availability of energy and other important resources must be of
critical importance in optimizing the functioning of any organism, and in coping with unusual or unwanted demands made by the environment. The thermodynamics of such
nonideal processes should therefore be an appropriate way to chart the organism’s coping
strategies, as outlined in the next section.
Kapha, being responsible for storage, becomes identified in the simplest single cells
with the cell membrane and the cell wall, basic
reserves for such a cell to call on in hard times,
and the only sizeable structures in a prokaryotic cell. On a molecular level, kapha thus becomes identified with lipids and polysaccharides, the molecular basis for membranes and
cell walls, respectively.
In the human body vata and kapha are, dynamically speaking, found to be in opposition
to each other. Correspondingly, in the single
cell, transport and storage functions both manifest in the cell membrane and cell wall, but in
completely different ways, so that they would
naturally compete for ATP available in that location. The opposition would appear to be
The above identifications of the three doshas
are of interest because their functions correspond simply and obviously to those of the
doshas identified by Ayurveda in the human
body. For example, the main subdosha of vata is
apana, which governs colon (and aspects of kidney) function. The colon is well known to be
responsible for nutrient uptake, water absorption, and as the organ that ends in the rectum
and anus, the elimination of waste matter. The
kidney regulates water balance. All these functions correspond to those of the cell membrane
in single cells enumerated above. Prana, the
best-known vata subdosha, governs movement
of the mind. It is ultimately responsible for
gross mechanical motion of the body. The
transmission of nerve impulses in the central
nervous system (CNS) (primarily the domain
of vata) relies completely on cellular input/output processes: first, those governing sodium/
potassium balance in nerve axons, and second,
neurotransmitter release and reabsorption at
Passing to eukaryotic single cells, the correspondence continues. The motion of single cells
undergoing chemotaxis is governed by sensors
on the membrane connecting to mechanisms
regulating cell shape, also attached to the membrane. Hence it is not surprising to find vata
identified in the human body as the dosha responsible for motion of many different kinds—
samana for intestinal peristalsis, udhana for
eructation, etc., vyana for horripilation (goose
bumps) and shivering.
Similarly, for pitta, its identification as being
responsible for energy production and regulation in single cells has many expressions in the
doshas on the level of the body. Pachaka, the
chief pitta subdosha, is responsible for the production of digestive juices in the stomach,
while ranjaka governs bile production and other
aspects of liver metabolism (such as the stomach, a pitta organ). Alochaka governs the eyes,
which are an extension of the CNS. Photosensitivity here is parallel to photoenergetic
processes in single cells, clearly a pitta responsibility. Sadhaka is more subtle and assigned to
the heart. Bhrajaka governs transformations in
AYURVEDIC PHYSIOLOGY AND ETIOLOGY
the skin, e.g., pigmentation regulating light entering the body.
Kapha in the human body is said to coordinate structure, including cohesion and lubrication. Cohesion results from reactions and interactions at the cell wall, the original domain
of kapha. Mucous production is governed in the
stomach by kledaka; in the lungs by avalambaka;
saliva by bhodaka; spinal fluid by tarpaka;
sinovial fluid by shleshaka, which is concerned
with joints, connections and cohesion of all
kinds. All these can be traced to the functions
of kapha in single cells: The function of kapha in
single cells is storage, using, e.g., polysaccharides and lipids; similarly, mucus is polysaccharide, while other lubrication may use lipids.
These correspondences suggest a continuity
of function of vata, pitta, and kapha throughout
the history of life on earth; their simplicity demands a correspondingly simple explanation.
It would appear that the strategies, which
maintain processes of control in single cells and
other living organisms, possess an underlying
continuity throughout their biologic development, starting from the microscopic level of
regulation of biochemical processes in single
cells, and proceeding to the macroscopic level
of control processes regulating whole organisms and their subsystems.
This means that during evolution, certain
factors are of a primary and unchanging nature
whereas others are secondary and can be more
subject to alteration. Thus, on a microscopic
biochemical level, the sequences of amino acids
in enzymes and the corresponding base sequences in the nucleic acids may vary. In contrast, the choice of molecules for the subunits
of proteins and nucleic acids, once made, do
not: genes may change with the passing of generations, but the genetic code is an invariant of
In a similar way, on the macroscopic level of
a whole organism, the fundamental strategies
of control by which behavior is regulated need
to remain invariant. This seems to be true not
only in terms of the systems theory reasoning
given at the outset, but also to extend to the
level of molecular structures each dosha uses
to exert control throughout biological history.
Active transport in cell membranes is the domain of vata, material turnover related to en-
ergy production of pitta, polysaccharides and
lipids of kapha. Their corresponding functions
in different subsystems at different stages of biologic development continue to make use of
these basic domains in the processes they regulate.
It is proposed, therefore, that throughout history, the processes of biologic development
have maintained similar strategies of control to
those used in the original cells, adding to and
building on them as appropriate, but without
fundamental alteration. This suggests the following understanding of doshas. Throughout
the historical development of living organisms,
there have existed three strategic domains of
functional control, which have retained their
functional modalities and that Ayurveda identifies as the three doshas, vata, pitta, and kapha.
This suggests that the three doshas may be considered as fundamental to life as proteins, nucleic acids, and the genetic code. It could even
be argued that they are more fundamental, for
the systems theory argument identifying them
would remain valid for other conceivable biologic systems evolving on other planets where
enzymes, genes, and the genetic code were constituted in a chemically different way.
The doshas and subdoshas would be of secondary interest to any system of medicine were
it not for the fact that they provide an etiologic
system of fundamental importance. Doshabased etiology provides as significant a description of the health of an organism as of its
For the human organism, Ayurveda identifies a state of perfect health: when all three
doshas (and other aspects of the system) are
functioning in balance, sama-dosha (Sharma,
1981–1996; Sharma and Clark, 1998). Each dosha
can go out of balance by measurable degrees,
meaning that the proportion of its energy is not
correct with respect to the other doshas (see
Table 4). A continuing imbalance of a dosha, resulting from some failure of regulation of metabolic processes, is said to produce an accumulation of the resulting problem or impurity (the
literal translation of the word dosha).
TABLE 4. STAGES
Perfect balance—All of the doshas are functioning correctly in correct proportion to each other and in their right
Imbalance—Some aspect of the above is not satisfied.
Stage I: Accumulation—A disproportion of a particular dosha or subdosha increases or accumulates.
Stage II: Aggravation or Vitiation—The dosha or subdosha becomes overstimulated and may go into a wrong
channel. The dosha or subdosha begins to act in an inappriate way.
Stage III: Spreading or Migration—The dosha or subdosha moves beyond the location of its normal function.
Stage IV: Condensation or Localization—The dosha or subdosha localizes in an inappropriate region.
Stave V Manifestation—Pathologic symptoms manifest in the new location, e.g. a boil, arthritis or angina.
Stave VI: Bursting (possibly)—An acute crisis occurs as with an aneurysm, an embolism or an infarction.
Only stages V and VI have recognizable symptoms on a gross level. Stages I–IV do not and must be detected by
direct measurement of doshas themselves.
As imbalance accumulates to a higher degree, the dosha changes to a condition described
as vitiated or aggravated, in which it is overstimulated and may go into inappropriate
channels and even push another dosha or subdosha out of balance. In the next degree of imbalance, the boundaries of the normal region of
its operation become violated, the dosha’s condition is described as spreading, resulting in its
migration, and eventual condensation or localization in another, inappropriate, location on a
permanent basis. It is only after these stages of
imbalance have developed that the final two,
pathologic, stages occur: manifestation and,
possibly, bursting as in a boil or embolism.
According to Ayurveda, no pathologic condition, even that resulting from an acute infection, can develop without such a sequence of
identifiable stages taking place. So, Ayurveda
can identify four stages of departure from “perfect balance,” charting “loss of health,” before
any actually pathologic condition manifests.
Ayurveda thus offers the possibility of “nipping any condition in the bud” before it
develops into a problem. Ayurveda can also
identify a pathologic condition in terms of corresponding displacements of the various doshas
and subdoshas, because specific conditions have
corresponding specific dosha/subdosha signatures.
But to what do the concepts of perfect balance, imbalance, etc., correspond? Although
specific instances might be recognizable biochemically, these concepts do not have any
precise correlate in conventional biomedical
terminology. The various terms used by Ayurveda to describe departure from perfect bal-
ance or perfect physiologic functioning seem
parallel to a description of a journey across a
phase diagram. In one phase, a particular condition holds that seems more or less stable, but
that makes a drastic change of type at the edge
of that phase. In the next phase a different general condition holds, which may, if a phase
transition is taking place, become more accentuated as that region is transited.
This may indeed be a pertinent parallel and
more than a mere analogy. Consider regulatory
control in complex systems such as those involved in the biochemical pathways in living
cells (Eigen and Schuster, 1979). In the last section, we saw that the thermodynamics of entropy producing (and thus nonequilibrium)
systems should be central to quantitative treatments of cell functioning. In this context, it is
well-understood from the work of Ilya Prigogine (1980) on nonequilibrium chemical
processes of the kind found in cells and more
complex living systems, that they exhibit complex behaviors that can be represented in terms
of phase diagrams for the corresponding chemical potentials and other free energies.
The major necessary condition identified by
Prigogine (1980) for such behavior to take place
is that there should be cyclic processes involved, for example through the self-catalysis
of particular chemical reactions. Now, it is well
known from control theory, that feedback is a
necessary condition for regulation; and in a system of chemical reactions, any feedback loop
will yield a cycle (Eigen and Schuster, 1979).
Biochemical processes of regulation in a living cell therefore cannot but satisfy Prigogine’s
condition. This implies that regulation ascribed
AYURVEDIC PHYSIOLOGY AND ETIOLOGY
to the three doshas should be describable in
terms of thermodynamic phase diagrams precisely parallel to Ayurvedic descriptions of
how the doshas “go out of balance.” Indeed,
useful research could be conducted on, for example, the thermodynamics that this implies or
on details of specific pathologies and how they
relate to other modalities of complementary
and alternative medicine.
The hypothesis that stages of dosha imbalance
can be described by phase diagrams is consistent with another, general, observation about
doshas from Ayurvedic practitioners. They are
not simply mechanical concepts, as might be
implied from the definition in terms of systems
and control theories. Rather, they come to be
perceived more as subtle values of energy,
which may be activated in different regions of
the body to a greater or lesser degree at different times and under different circumstances, almost as if they had field-like qualities. It seems
intuitively satisfying to consider that patterns
of activation of such empirically detected
“fields” may be described in terms of phase diagrams resulting from their various mutual interactions.
AGGRAVATION OF DOSHAS BY
Another analysis of dosha function can be
made by considering the kinds of food molecule, which tend to aggravate or pacify each
dosha (see Table 5).
Failure to consume enough water, or an excess of dry food, aggravates vata. An excess of
chili or other hot food, or heat, aggravates pitta.
An excess of sweet or fatty foods aggravates
kapha. These confirm the connections of vata to
homeostasis and water balance; pitta to regula-
TABLE 5. AGGRAVATION
tion of heat and metabolism; and kapha to polysaccharides and lipids.
On the single cell level, pacification of vata is
caused by foods that provide source molecules
for energy, enzyme, and macromolecule synthesis, implying that less gross motion will then
be required to search for new food; aggravation of pitta is caused by molecular types increasing the rate of digestion, e.g., acid/sour;
aggravation of kapha is caused by molecules
making the organism overweight (sugars, fats).
These observations are possible further confirmation of one of the fundamental suggestions of this paper, that vata, pitta, and kapha
present concepts applicable to single cells as
well as to human beings, and that tracing the
continuity of their development will show how
they are valid for all living organisms.
The ideas offered in this paper have seminal
Ayurveda’s doshas can be identified as regulatory control factors for fundamental physiologic processes in living systems that maintain
their identity throughout biologic history: vata
and its subdhoshas regulating input/output
processes and motion; pitta and its subdoshas
regulating throughput, turnover, and hence energy; and kapha and its subdoshas regulating
storage, structure, and lubrication.
Thermodynamic phase diagrams for nonequilibrium processes in the cyclic sets of
chemical reactions governing the appropriate
regulatory systems provide a starting point for
elucidating Ayurveda’s dosha-based etiology.
These suggestions offer the basis for many
kinds of investigation into the nature, inheritance, and systematic development of func-
tional control in biologic systems, from the simplest organisms to the most complex ones. For
medicine, the idea that states of health can legitimately be described in terms of phase diagrams could prove to be particularly rich and
yield new insights into the classification of
pathologies recognized by conventional Western medicine, as well as other modalities of
complementary medicine. These suggestions
also offer fresh approaches to therapy for any
Comparative and integrative paradigmatic
analysis, such as that offered in this paper, is a
necessary step in moving toward a genuinely
integrated approach to health care. It is necessary in order for us to move beyond the superficial situation where technologies with documented effects, but seemingly implausible
explanatory models, are only applied by believers. In the new, more developed, paradigm,
theory as well as technology is understood and
enriches our understanding of the processes of
life in the context of explaining specific bodily
processes. Taken together, the documented
technologies and their theory then become universally available as means of influencing such
physiologic processes in the direction of improving human health.
I would like to express my gratitude to His
Holiness Maharishi Mahesh Yogi who has revived the ancient Vedic sciences, deeply studying their relationship to the sciences of the
West, encouraging his students to further this
exploration. This paper draws on his scholarship. I would also like to thank Dr. Gerry
Bodeker, Professor Shinde, and Dr. Donn Brennan for very helpful advice and comments on
this paper, and Dame Miriam Rothschild and
Professor Lynne Margulis for conversations
and encouragement during earlier stages of its
development. I am particularly grateful to Professor John Fagan of Maharishi University of
Management for his hospitality and encour-
agement and to his associates, Dr. Phil Tomlinson and Dr. Charlotte Beck for their helpful
insights. Finally, I am most grateful to Dr. Geoffrey Clements, Dr. Steven Cross, and Geoff
Gay for their encouragement and support.
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Address reprint requests to:
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London W8 4QA