Ayurveda literally means "Science of life"  or "Knowledge of life". This life-care, healthcare and disease care system deals with good, bad, blissful and sorrowful life. It describes the beneficial and harmful factors for life. [Cha.Sa. Sutra Sthana 1/41] Ayurveda deals with guidelines for preservation, protection of health and prevention of disease. It is not merely a system of medicine, rather it is a way of life to increase lifespan by preventing or delaying the aging process. 
|Section/Chapter||Ayurveda / Ayurveda|
|Reviewer & Editor||Basisht G.|
|Affiliation||Charak Samhita Research, Training and Development Centre, I.P.G.T.& R.A., Jamnagar|
Ayurvedic definition of health described by Sushruta clearly states what health is with five components.[Su.Sa. Sutra Sthana 15/48]  These five components need to be in a state of equilibrium to attain and preserve health. Their disequilibrium is precursor to disease. Each component can be identified clinically by an Ayurvedic physician to act upon and are described as follows:
- Three dosha (interaction between epigenes and genes)- vata, pitta, and kapha - are the fundamental physiological governing regulators of the body,
- Agni (metabolic and digestive processes by various enzymes and interaction with microsomes)
- Dhatu (principles that uphold the formation of body tissues).
- Mala or bodily wastes produced that are either reutilized or excreted well, and
- The sense organs, mind and the Soul
In addition, Ayurveda also emphasizes on normal physique, sensory-motor functions, appetite, thirst, endurance to heat, cold and exertion for assessment of status of health. [Cha.Sa.Sutra Sthana 21/18-19]
On the other hand, allopathic system is primarily an excellent disease-care system  with vague understanding of what health is. The World Health Organization defines health as “State of complete physical, mental and social wellbeing and not merely the absence of disease or infirmity.” It is obvious that there is no clear understanding of components of physical, mental and social wellbeing. The advantage of Ayurveda over the current medical system is its core principles of human ecosystem, personified biological concepts in accordance with the body type and nature. Though, Ayurveda finds its roots in India, the core principles are universal and applicable across globe. This is clearly visible through its increasing popularity in western world.
What is Ayurveda?
The careful, critical and unbiased study of the classical Ayurveda texts show that by the time compendiums (Samhita-granthas) were compiled, the Science and Art of Ayurveda had already passed through the stage of specialization and, knowledge flowing from different specialized fields of medicine and allied sciences generalized, simplified and principles enunciated. Thus, Ayurveda is referred to as Science and Art of life.
Source of Ayurveda
The Vedic medicine is developed in India during the period 2000-1000 B.C. and considered as one of the oldest systems of medicine in the world. There are four major ancient Indian compendiums of knowledge (veda) named Rigveda, Yajurveda, Samaveda, and Atharvaveda. Rigveda is the oldest recorded document regarding use of plants as medicine in India, and this tradition continued in another ancient text, Atharvaveda (1500-1000 BC), which described more plants and introduced basic concepts. Ayurveda physicians owe their loyalty to the Atharva Veda because this deals with the treatment of diseases not only by herbs but also resorting to various practices like sacrifices, prayers, and chants, charity, moral discipline, the atonement of sins, austere practices like fasts, etc. These are advocated for treatment as well as for living a healthy, long life. Thus,it is sourced as a section (upaveda) developed from Atharvaveda. [Cha.Sa. Sutra Sthana 30/21]
What is Ayu?
Ayu (life) implies the conjunction of physical body, senses, mind and soul. It is known by the synonyms dhari (that which sustains), jivita (that which is live), nityaga (that which is in continuum), and anubandha (that which is interdependent, or a link between past life and the future life).[Cha.Sa. Sutra Sthana 1/42]
Thus life (Ayu) is continuity(anuvritti) of consciousness (chetana), liveliness (jeevita), bonding with the body (anubandha) and preserving vitality(dhari).[Cha.Sa. Sutra Sthana 30/22] .
Life is not merely the existence of machine-like physical structure of body. The conscious interaction of soul, mind and sense organs makes it live. Therefore these are essential components of Ayurvedic biology of human beings.
Scope of Ayurveda
Ayurveda is the source of knowledge that teaches about or deals with Ayu. Through its virtues, it imparts the knowledge of joy and suffering, benefit and harm, and authentic/authoritative and unauthentic/unreliable (sources of information). It also informs about the lifespan and substances with properties and actions that result in the same. This is dealt with in the entire text of Charak Samhita at various appropriate contexts.[Cha.Sa. Sutra Sthana 30/23]
Thus, Ayurveda deals with good, bad, bliss and sorrow in life, and with (what is) wholesome and unwholesome for it, longevity, and about what Ayu (life) is in itself.[Cha.Sa. Sutra Sthana 1/41]
Benefits of following Ayurveda for good life
The following are characteristics of happy and healthy life. These are indeed benefits of following Ayurveda.
People whose body and mind are disease-free, and those who are endowed with youth, enthusiasm, strength, virility, reputation, manliness, courage, knowledge of arts and sciences, healthy senses, objects of sensory perceptions, ability of the sensory organs, riches and various luxurious articles for enjoyment, and who can achieve whatever they want and think about wellness can enjoy a happy life. The people with opposite characteristics have sad life. Those who are the well-wishers of all beings, who do not wish to take other's wealth, who are truthful, peace loving, who are thoughtful before taking action, who are vigilant, who experience the three important objectives of life (righteousness, wealth and desire) without one affecting the other, who respect superiors, who are endowed with the knowledge of arts, sciences and tranquility, who serve the elders, who have full control over lust, anger, envy, arrogance and pride, who constantly indulge in various types of charity, meditation, acquisition of knowledge and quiet life (solitude), who have full spiritual knowledge and are devoted to it, who work both for the present as well as for the next life, and are endowed with memory and intelligence lead a useful rather beneficial life, while others don't. [Cha.Sa. Sutra Sthana 30/24]
The above are clinical parameters of good quality of life.The same assessment parameters are categorized under heads of physical wellbeing, psychological wellbeing, independence and social wellbeing reflected in the quality of life scale by the World Health Organization. 
Signs of decrease in lifespan
The decrease of lifespan is signaled by various sudden abnormal changes in the sensory perception, objects of perception, mind, intellect, and movement. These signals help in predicting the remaining lifespan and death of an individual at a particular moment. The signals include cessation of all activities (pravritti uparama), death (marana), transient changes (anityata), restriction in vital functions (nirodha). If the signs are absent, the lifespan is unlimited from the prognostic point of view. In Ayurveda, life span is determined by the characteristics of natural constitution.[Cha.Sa. Sutra Sthana 30/25]
Objective of Ayurveda
The prime objectives of this science is to preserve the health of the healthy and cure the disease of the unhealthy.[Cha.Sa. Sutra Sthana 30/26] Thus Ayurveda focuses on the preservation and promotion of health and management of diseases.
Authenticity and eternal qualities of Ayurveda
Ayurveda is eternal because It has no beginning and its characteristics are self-evident., Ayu (the combination of body, its organs, mind, and soul) and intelligence about Ayu (knowledge about Ayu) are perpetual. The knower becomes eternal after knowing Ayurveda. Concepts such as happiness and suffering (i.e., health and illness), therapeutics and pathogens, etc. - their causes, signs, and perpetuation are all eternal. [Cha.Sa. Sutra Sthana 30/27] The principles described in Ayurveda texts are universal, time tested and stand true on scientific validation. For example, the theory of similar and dis-similar (Samanya Vishesha siddhanta) is applicable universally which is of immense importance.
Healthcare system of Ayurveda
The healthcare system of Ayurveda includes four components like physician, therapeutic substance, care taker and patient. Ayurveda emphasizes on importance of best qualities of these components to achieve maximum efficacy in healthcare management.[Cha.Sa.Sutra Sthana 9]
The ayurvedic system of healthcare owes its own fundamental principles and methodology in every aspect. In academic perspectives, the compendiums of Ayurveda elaborately describes the standards of a medical treatise; writing, teaching and learning methodologies; communication and debate codes with the dispute resolution techniques.[Cha.Sa. Vimana Sthana 8/3-67]
Understanding human being
In perspective of medical and human biological understandings, the origin of human being, fundamental elements, unification with soul, conception, embryonic development, prenatal care and its benefits to prevent congenital disorders, the anatomical and physiological concepts, fundamental body constitution and psychological traits, statistical analysis and classification, development into holistic human being(purusha) are described. The physiological aspects of body i.e. dosha, dhatu and mala, biological transportation systems, processes of digestion and metabolism are extensively discussed with analogies.
Diagnostic and pathological perspectives
In understanding pathological abnormalities and disease diagnosis, methods of clinical examination[Cha.Sa. Vimana Sthana 79-133]; diagnostic methods without any invasive techniques; diagnosis by perception, observation, palpation and interrogation methods[Cha.Sa.Vimana Sthana 4/3-8]; classification of diseases based on abnormalities of basic body constituents[Cha.Sa, Sutra Sthana Chapter 20]; six stages of disease progression; opportunistic susceptibilities for disease states; and comprehensive knowledge of pathologies of major diseases[Cha. Sa. Nidana Sthana] is present. The tools to know endogenous and exogenous diseases with their important causes, features, pathogenesis are also described. The near death or fatal signs and factors to be considered in examination of a critically ill patient are described in Indriya sthana.
Pharmaco-therapeutic and dietary aspects
Ayurveda deals with basic understanding of fundamental constitution of any substance of medicinal or dietary value, its interactions with human biology, pharmaco-therapeutic activity, indications and contra-indications, suitability and heterogenicity, its processing guidelines, storage guidelines, safety and efficacy profiles.[Cha.Sa.Sutra Sthana chapters 25-28] Classification of herbs is based upon their activity profile.[Cha.Sa.Sutra Sthana chapters 1-4] Classification of dietary substances is based upon their forms and cooking methods. Cha.Sa. Sutra Sthana Chapter 27 Special dietary guidelines are described to achieve greater health benefits. Behavior guidelines, codes of conducts are described to prevent lifestyle disorders. Cha.Sa. Sutra Sthana Chapter 8
Preventive and curative aspects
Good portion of the compendiums deal with guidelines of preservation, promotion and protection of health.[Cha.Sa.Sutra Sthana chapters 5-8] The management of diseases with purification procedures, pacification treatments and surgery are elaborated in respective sections[Cha.Sa.Chikitsa Sthana chapters 1-30].Five procedures of purification (Panchakarma), six methods of management (shadvidhopakrama), application of alkali, cautery and leeches are included in main forms of treatment.
Eight specialties of Ayurveda
There are eight main branches of Ayurveda:[Cha.Sa. Sutra Sthana 30/28]
- Kayachikitsa (Internal Medicine)
- Shalakya (Otorhinolaryngology (ENT) + Ophthalmology)
- Shalya (Surgery)
- Visha gara vairodhika prashamana or Agada tantra (Toxicology)
- Bhutavidya (Psychiatry)
- Kaumarbhrityakam ( Gynecology, Obstetrics and Pediatrics)
- Rasayanam (Science of rejuvenation) and
- Vajikaranam (Science of sexual health and aphrodisiac).
The details about these specialties are given in context of Chikitsa Sthana. Each of these specialties are developed in current era in terms of education, research and practices.
At present, Ayurveda is taught as an under-graduate medical course governed by Central Council of Indian Medicine under Ministry of AYUSH, Government of India. There are 339 colleges to conduct Bachelor of Ayurveda Medicine and Surgery (B.A.M.S.) course in India. Various international institutes conduct post graduate courses for specialization and Ph.D. programs for research in fourteen departments of Ayurveda. Some of the renowned institutes are enlisted below :
- Institute for Post Graduate Teaching and Research in Ayurveda, Gujarat Ayurved University, Jamnagar,India
- National Institute of Ayurveda, Jaipur,India
- Faculty of Ayurveda, Banaras Hindu University, Varanasi, India
- All India Institute of Ayurveda, New Delhi
The list of institutes that conduct above courses can be found here.
The Madhav Nidana, Bhavaprakash and Sharangadhara Samhita are followed as three other important texts. The texts are published online by National Institute of Indian Medical Heritage, Hyderabad, India.
More than 4400 entries of published books covering over 19 different subjects are available in Database ‘International Catalogue of Ayurvedic Publications' prepared by Institute for Post Graduate Teaching and Research in Ayurveda in collaboration with World Health Organization.
Research Journals and Database
In India, research in Ayurveda is undertaken by the Ministry of AYUSH, through a national network of research institutes.. Peer reviewed journals like AYU and Ancient Science of life publish research articles on various topics of Ayurveda. The database like AYUSH research portal and Digital Helpline for Ayurveda Research Articles (DHARA) are available for searching more than 10000 research articles published on Ayurveda. A directory for researches in Ayurveda comprising more than 20000 research titles and 1000 complete post graduate theses on Ayurveda is published online.
Ayurveda as a healthcare system can restore the innate intelligence of the body and awareness for healing. Ayurvedic therapies can affect both the genetic and phenotypic expression of life. It can be appreciated through the science of epigenetics. The epigenetic factors in life affect the phenotype in a positive or negative way, and indirectly affect the genetic expression in a positive or negative way, which can be transmitted to the progeny. Ayurveda covers both aspects of life – genetic and phenotypic – and is a comprehensive, holistic, and personalized system of health care.
A good scientific evidence exists to support the safety and efficacy of Ayurveda therapies, herbs, classical medicines, proprietary medicines. Attempts are being made to organize the data from classical compendiums and published researches.
Efficacy of Ayurveda in contemporary healthcare systems
Ample evidence is found through researches on various topics of Ayurveda to show safety and efficacy. It can be seen in the vidhi vimarhsa section of each chapter of this Charak Samhita New Edition.
Sharma H. et.al. has studied and analyzed over 130 research works to observe efficacy of Ayurveda in healthcare management. It is concluded that the Ayurveda therapies are time tested as a natural health care system and comprehensively treat the patient as a whole. Research over the last 100 years has shown encouraging results of various ailments, especially chronic disorders.
A 6 month controlled clinical trial compared two Ayurvedic formulations of plant extracts against the natural product glucosamine sulfate and the drug celecoxib in 440 people with knee osteoarthritis. In this study , Ayurvedic formulations (combination of Tinospora cordifolia, Zingiber officinale, Emblica officinalis, Boswellia serrata) significantly reduced knee pain and improved knee function. The results were equivalent to glucosamine and celecoxib.In another double-blind, randomized, placebo-controlled pilot study on 40 patients of rheumatoid arthritis, the efficacy of Ayurveda, Methotrexate, and their combination was compared. All three treatments were observed equally effective. Adverse events were lower in Ayurveda treated group.
Safety and pharmacovigilance of Ayurveda medicines
Ayurveda emphasizes judicious use of any herb, medicine or therapy only after proper analysis of status of individual (rogi bala pariksha), intensity and condition of disease (vyadhi bala and awastha). Personalized medicine as per suitability of the individual shall be prescribed after complete therapeutic knowledge of medicine. Ayurveda strongly denounces haphazard use of any medicine.[Cha. Sa. Sutra Sthana 1/122-135] Any drug/management/procedure which, when administered, produces any untoward effect other than expected beneficial action is not considered a perfect treatment. Considering the need of documentation of adverse effects due to imperfect treatment, pharmacovigilance program of Ayurveda medicines and therapies is started. 
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