Dosha

Dosha (Sanskrit: दोषः, IAST: doṣa) is a central term in ayurveda originating from Sanskrit, and which refers to three categories or types of substances that are believed to be present conceptually in a person's body and mind. These Dosha are assigned specific qualities and functions. These qualities and functions are affected by external and internal stimuli received by the body. Beginning with twentieth-century ayurvedic literature, the "three-dosha theory" (Sanskrit: त्रिदोषोपदेशः, tridoṣa-upadeśaḥ) has described how the quantities and qualities of three fundamental types of substances called wind, bile, and phlegm (Sanskrit: वात, पित्त, कफ; vāta, pitta, kapha) fluctuate in the body according to the seasons, time of day, process of digestion, and several other factors and thereby determine changing conditions of growth, aging, health, and disease.
Doshas are considered to shape the physical body according to a natural constitution established at birth, determined by the constitutions of the parents as well as the time of conception and other factors. This natural constitution represents the healthy norm for a balanced state for a particular individual. The particular ratio of the doshas in a person's natural constitution is associated with determining their mind-body type including various physiological and psychological characteristics such as physical appearance, physique, and personality.
The ayurvedic three-dosha theory is often compared to European humorism although it is a distinct system with a separate history. The three-dosha theory has also been compared to astrology and physiognomy in similarly deriving its tenets from ancient philosophy and superstitions. Using them to diagnose or treat disease is considered pseudoscientific.
Doshas are purely imaginary; their existence is not supported by any evidence.
The ayurvedic notion of doshas describes how bad habits, wrong diet, overwork, etc., may cause relative deficiencies or excesses which cause them to become imbalanced in relation to the natural constitution (prakriti) resulting in a current condition (vikriti) which may potentially lead to disease. For example, an excess of vata is blamed for mental, nervous, and digestive disorders, including low energy and weakening of all body tissues. Similarly, excess pitta is blamed for blood toxicity, inflammation, and infection. Excess of kapha is blamed for increase in mucus, weight, oedema, and lung disease, etc. The key to managing all doshas is taking care of vata; it is taught that this will regulate the other two.
The doshas derive their qualities from the five elements (Sanskrit: पञ्चमहाभूत; pañca-mahābhūta) of classical Indian philosophy.
Yoga is a set of disciplines, some that aim to balance and transform energies of the psyche. At the roots of vata, pitta and kapha are believed to consist of its subtle counterparts called prana, tejas and ojas. Unlike the doshas, which in excess create diseases, this is believed to promote health, creativity and well-being.
Ultimately, ayurveda seeks to reduce disease, particularly those that are chronic, and increase positive health in the body and mind via these three vital essences that aid in renewal and transformation. Increased prana is associated with enthusiasm, adaptability and creativity, all of which are considered necessary when pursuing a spiritual path in yoga and to enable one to perform. Tejas is claimed to provide courage, fearlessness and insight and to be important when making decisions. Lastly, ojas is considered to create peace, confidence and patience to maintain consistent development and sustain continued effort. Eventually, the most important element to develop is ojas, believed to engender physical and psychological endurance. Aims to achieve this include ayurvedic diet, tonic herbs, control of the senses, a devotion and most importantly celibacy.
Writing in the Skeptical Inquirer, Harriet Hall likened dosha to horoscope. She found that different online dosha websites gave different results in personalized quizzes, and summarized that "Ayurveda is basically superstition mixed with a soupçon of practical health advice." Professional practitioners of ayurveda in the United States are certified by the National Ayurvedic Medical Association Certification Board, which advocates for the safe and effective practice of ayurveda. Alternative medicines used in ayurvedic treatments have been found to contain harmful levels of lead, mercury, and other heavy metals. Even some Ayurvedic scholars have expressed reservations about the Tridosha theory, arguing that it should be viewed as a useful framework rather than a definitive, universally applicable concept, and instead be employed as a heuristic tool to inform practice and decision-making.