The earliest extant systematic account of yoga and a bridge from the earlier Vedic uses of the term is found in the Hindu Katha Upanisad (Ku), a scripture dating from about the third century BCE[…] [I]t describes the hierarchy of mind-body constituents—the senses, mind, intellect, etc.—that comprise the foundational categories of Sāmkhya philosophy, whose metaphysical system grounds the yoga of the Yogasutras, Bhagavad Gita, and other texts and schools (Ku3.10–11; 6.7–8).
Alexander Wynne observes that formless meditation and elemental meditation might have originated in the Upanishadic tradition. The earliest reference to meditation is in the Brihadaranyaka Upanishad, one of the oldest Upanishads. Chandogya Upanishad describes the five kinds of vital energies (prana). Concepts used later in many yoga traditions such as internal sound and veins (nadis) are also described in the Upanishad. Taittiriya Upanishad defines yoga as the mastery of body and senses.
An increase in fiber intake is also recommended for regulating bowel movements. Other methods of weight loss include use of drugs and supplements that decrease appetite, block fat absorption, or reduce stomach volume. Bariatric surgery may be indicated in cases of severe obesity. Two common bariatric surgical procedures are gastric bypass and gastric banding. Both can be effective at limiting the intake of food energy by reducing the size of the stomach, but as with any surgical procedure both come with their own risks that should be considered in consultation with a physician. Dietary supplements, though widely used, are not considered a healthy option for weight loss. Many are available, but very few are effective in the long term.
^ Andrew J. Nicholson (2013). Unifying Hinduism: Philosophy and Identity in Indian Intellectual History. Columbia University Press. p. 26. ISBN 978-0-231-14987-7., Quote: "From a historical perspective, the Brahmasutras are best understood as a group of sutras composed by multiple authors over the course of hundreds of years, most likely composed in its current form between 400 and 450 BCE."
Yoga gurus from India later introduced yoga to the West, following the success of Swami Vivekananda in the late 19th and early 20th century with his adaptation of yoga tradition, excluding asanas. In the 1980s, a very different form of modern yoga, with an increasing number of asanas and few other practices, became popular as a system of exercise across the Western world. Yoga in Indian traditions, however, is more than physical exercise; it has a meditative and spiritual core. One of the six major orthodox schools of Hinduism is also called Yoga, which has its own epistemology and metaphysics, and is closely related to Hindu Samkhya philosophy.
The Bhakti movement was a development in medieval Hinduism which advocated the concept of a personal God (or "Supreme Personality of Godhead"). The movement was initiated by the Alvars of South India in the 6th to 9th centuries, and it started gaining influence throughout India by the 12th to 15th centuries. Shaiva and Vaishnava bhakti traditions integrated aspects of Yoga Sutras, such as the practical meditative exercises, with devotion. Bhagavata Purana elucidates the practice of a form of yoga called viraha (separation) bhakti. Viraha bhakti emphasizes one pointed concentration on Krishna.
In the early 11th century, the Persian scholar Al Biruni visited India, lived with Hindus for 16 years, and with their help translated several significant Sanskrit works into Arabic and Persian languages. One of these was Patanjali's Yogasutras. Al Biruni's translation preserved many of the core themes of Patañjali 's Yoga philosophy, but certain sutras and analytical commentaries were restated making it more consistent with Islamic monotheistic theology. Al Biruni's version of Yoga Sutras reached Persia and Arabian peninsula by about 1050 AD. Later, in the 16th century, the hath yoga text Amritakunda was translated into Arabic and then Persian. Yoga was, however, not accepted by mainstream Sunni and Shia Islam. Minority Islamic sects such as the mystic Sufi movement, particularly in South Asia, adopted Indian yoga practises, including postures and breath control. Muhammad Ghawth, a Shattari Sufi and one of the translators of yoga text in 16th century, drew controversy for his interest in yoga and was persecuted for his Sufi beliefs.
If the meaning of yoga is understood as the practice of nirodha (mental control), then its goal is "the unqualified state of niruddha (the perfection of that process)", according to Baba Hari Dass. In that context, "yoga (union) implies duality (as in joining of two things or principles); the result of yoga is the nondual state", and "as the union of the lower self and higher Self. The nondual state is characterized by the absence of individuality; it can be described as eternal peace, pure love, Self-realization, or liberation."