Ayurveda (आयुर्वेद Sanskrit: ayu life; veda knowledge of) or Ayurvedic medicine, is a more than 6,000 year old comprehensive system of medicine based on a holistic approach rooted in Vedic culture and Hinduism. Its conspicuous use of the word Veda, or knowledge, reveals its role in early Hinduism and describes its hallowed place in India. Ayurveda also had a tradition of surgery. Two early texts (from centuries BCE) of Ayurveda are the Charaka Samhita and the Sushruta Samhita.

The Charaka and Sushruta Samhitās are compendiums of two traditions rather than texts authored by single authors. A third tradition is that of the Kāshyapas. The beginnings of these traditions dates to the 2nd millennium BC if not earlier because of the parallel information obtained in the Vedic Samhitās and the description in the Mahābhārata. There is much that is common in the texts, except that the Sushruta Samhitā is richer in the field of surgery. Part of the original Caraka Samhitā is lost, and the current version has several chapters by the Kashmiri scholar Dridhabala.

An attempt to reconcile the texts of Caraka and Sushruta was made by Vāgbhata the Elder in 2nd century BC in his Ashtānga Sangraha. The works of Caraka, Sushruta, and the Elder Vagbhata are considered canonical and reverentially called the Vriddha Trayi, "the triad of ancients"; or Brhat Trayi, "the greater triad." Later, Vāgbhata the Younger wrote the Ashtānga Hridaya Samhitā which is a lucid presentation of the Āyurveda giving due place to the surgical techniques of Sushruta. In the eighth century, Mādhav wrote his Nidāna, which soon assumed a position of authority. In the 79 chapters of this book, he lists diseases along with their causes, symptoms, and complications.

Ayurveda used inoculation for protection against smallpox. This was a consequence of the principle that like cures like on a small level, whereas at a grosser level opposites cure opposites. Ayurveda has employed certain toxic substances in small dosages for powerful healing effects, including its alchemical preparations. It also used various herbal and animal toxins like snake venoms. It has a whole science of toxicology called agada-tantra as one of the eight branches of traditional Ayurveda. This branch not only treated poisons but used them in certain conditions, generally in small dosages.

Ayurvedic idea is that the organism adapts to the environment and its food, climate etc. This principle of adaptation is called satyma. Through introducing small amounts of a germ, the organism can adapt to it and learn to resist it. Ayurveda became increasingly symptom-based, treating the symptoms of a disease rather than the root cause. It is important to note that Ayurveda was originally a consciousness based system of health care. Its philosophy, expressed in modern terms, is to strengthen the immune system.

Qualities

The simple essence of ayurveda is knowledge and awareness of the qualities of nature – called gurvadi gunah. By understanding the qualities inherent in the environment, in foodstuffs, in activities, etc., one gains an appreciation of their effects on the individual constitution through the principle of similarities; i.e., that similarities cause increase while dissimilarities cause decrease. Thus hot qualities in the environment or diet will increase hot qualities in the body.

The gurvadi gunah are listed in Vagbhata's Ashtanga Hrdayam as:

1. Guru (heavy) – laghu (light)
2. Manda (slow) – tikshna (quick, sharp)
3. Hima (cold) – ushna (hot)
4. Snigdha (unctuous) – ruksha (dry)
5. Slakshna (smooth) – khara (rough)
6. Sandra (solid) – drava (liquid)
7. Mrdu (soft) – kathina (hard)
8. Sthira (stable) – cala (mobile)
9. Sukshma (subtle) – sthula (gross)
10. Vishada (non-slimy) – picchila (slimy)

Since everything in the material world possesses combinations of the 20 qualities, ayurveda postulates that every material process or object can either harm or heal a person by influencing that person's unique original constitution (prakrti). An ayurvedic practitioner will assess the qualities of a disorder, the patient's unique prakrti, and his/her influencing factors to arrive at a treatment plan. The treatment plan will consist of using herbs, therapies, diet, etc., with opposite qualities so as to assist the patient in re-establishing their prakrti.

The Five Elements

According to the ancient Sankhya theory of cosmology, on which ayurveda is based, the five elements – pancamahabhuta – combine in different proportions to form the material world. Each element possesses different amounts of the above-mentioned gunas; thus each element has its unique qualitative nature. The elements are:

1. Akasha – ether or space
2. Vayu – air
3. Tejas or agni – fire
4. Apa or jala – water
5. Prthvi – earth

Some authorities state that the early European concept of five elements evolved from Ayurveda.

Doshas

The 3 main doshas (organizing qualities of intelligence) are Vata (resembles the classical elements ether and air), Pitta (fire), and Kapha (water and earth). All bodily processes are believed to be governed by a balance of the 3 doshas. Whichever dosha appears to dominate a person's behavior and physique is called his constitution type. Each constitution type has particular strengths and susceptibilities.

Vata

Vata, composed of air and space, governs all movement in the mind and body and must be kept in good balance. Too much vata leads to "worries, insomnia, cramps and constipation. Vata controls blood flow, elimination of wastes, breathing and the movement of thoughts across the mind." Vata activates the nervous system, hearing and speech; and expresses as enthusiasm and creativity. Vata also controls the other two principles, Pitta and Kapha, and is usually the first cause of disease.

Pitta

Pitta is said to be composed of fire and water; it governs "all heat, metabolism and transformation in the mind and body. It controls how we digest food, how we metabolize our sensory perceptions, and how we discriminate between right and wrong." Pitta must be kept in balance, too. "Too much Pitta can lead to anger, criticism, ulcers, rashes and thinning hair."

Kapha

Kapha consists of earth and water. "Kapha cements the elements in the body, providing the material for physical structure. This dosha maintains body resistance. Kapha lubricates the joints; provides moisture to the skin; helps to heal wounds; fills the spaces in the body; gives biological strength, vigor and stability; supports memory retention; gives energy to the heart and lungs and maintains immunity. Kapha is responsible for emotions of attachment, greed and envy; it is also expressed in tendencies toward calmness, forgiveness and love." Too much Kapha leads to lethargy and weight gain, as well as congestion and allergies.

In sum, Ayurveda represents a system that considers both the states of mind and body in its diagnosis and treatment. Ayurveda took into consideration the fact that many illnesses are caused by foreign agents and small organisms that may require aggressive intervention.

Today

Having lost state patronage during the British rule in India, Ayurveda is making a slow comeback. In practice in India, there are Ayurvedic doctors who are purists and others who choose to use it in combination with Western medicine.

Ayurveda is gaining lots of interest in the Western countries. Ayurvedic treatments in the West are primarily dietary and herbal due to lack of well educated Ayurvedic practitioners. Patients are classified by body types, or prakriti, which are determined by proportions of the three doshas. Illness and disease are considered to be a matter of imbalance in the doshas. Treatment is aimed at restoring harmony or balance to the mind-body system. Ayurvedic medicine is gaining in popularity around the world. There are a number of medical schools that teach Ayurveda.