Researchers have found that three sessions of the exercise a week can help fight off depression as it boosts levels of a chemical in the brain which is essential for a sound and relaxed mind.
Scientists found that the levels of the amino acid GABA are much higher in those that carry out yoga than those do the equivalent of a similarly strenuous exercise such as walking.
The chemical, GABA, is essential to the function of brain and central nervous system and which helps promote a state of calm within the body.
Low GABA levels are associated with depression and other widespread anxiety disorders.
The World Health Organization reports that mental illness makes up to fifteen percent of disease in the world. Anxiety and depression disorders both contribute to this burden and are associated with GABA receptor levels. Currently, these disorders have been successfully treated with pharmaceutical agents designed to increase GABA effectiveness.
Using magnetic resonance spectroscopic imaging, the researchers compared the GABA levels of eight subjects prior to and after one hour of yoga, with 11 subjects who did no yoga but instead read for one hour. The researchers found a twenty-seven percent increase in GABA levels in the yoga practitioner group after their session, but no change in the comparison subject group after their reading session. The acquisition of the GABA levels was done using a magnetic resonance spectroscopy technique developed by J. Eric Jensen, PhD, an assistant professor of psychiatry at Harvard Medical School and an associate physicist at McLean Hospital.
According to the researchers, yoga has shown promise in improving symptoms associated with anxiety, depression and epilepsy. “Our findings clearly demonstrate that in experienced yoga practitioners, brain GABA levels increase after a session of yoga,” said lead author Chris Streeter, MD, an assistant professor of psychiatry and neurology at BUSM and a research associate at McLean Hospital.
Yoga (Sanskrit, P?li: ??? yóga) refers to traditional physical and mental disciplines originating in India.The word is associated with meditative practices in Hinduism, Buddhism and Jainism. Within Hinduism, it also refers to one of the six orthodox (?stika) schools of Hindu philosophy, and to the goal towards which that school directs its practices. In Jainism, yoga is the sum total of all activities — mental, verbal and physical.
Major branches of yoga in Hindu philosophy include R?ja Yoga, Karma Yoga, Jnana Yoga, Bhakti Yoga, and Hatha Yoga. According to the authoritative Indian philosopher Sarvepalli Radhakrishnan, yoga, based on the Yoga Sutras of Patanjali, comprises one of the six main Hindu schools of philosophy (darshanas), together with Kapila’s Samkhya, Gautama’s Nyaya, Kanada’s Vaisheshika, Jaimini’s Purva Mimamsa, and Badarayana’s Uttara Mimamsa or Vedanta. Many other Hindu texts discuss aspects of yoga, including the Upanishads, the Bhagavad Gita, the Hatha Yoga Pradipika, the Shiva Samhita and various Tantras.
The Sanskrit word yoga has many meanings, and is derived from the Sanskrit root “yuj”, meaning “to control”, “to yoke” or “to unite”. Translations include “joining”, “uniting”, “union”, “conjunction”, and “means”. It is also possible that the word yoga derives from “yujir samadhau,” which means “contemplation” or “absorption.”[16] This translation fits better with the dualist Raja Yoga because it is through contemplation that discrimination between prakrti (nature) and purusha (pure consciousness) occurs.
Outside India, the term yoga is typically associated with Hatha Yoga and its asanas (postures) or as a form of exercise. Someone who practices yoga or follows the yoga philosophy to a high level of attainment is called a yogi or yogini.

Yoga can reduce the stress of cancer diagnosis and treatment experienced by childhood cancer patients and their parents, says a study.
As per the research, parents and adolescents showed a decrease in anxiety and increase in sense of well-being following yoga sessions conducted at the Children’s Hospitals and Clinics of Minnesota.
“Yoga is emerging as an effective complementary therapy in adult oncology. Promising benefits for decreasing symptom distress including fatigue, insomnia, mood, and stress resulting in improved quality of life,” said the authors of the study.
The authors explored a new area, focusing on childhood cancer patients and their families, noting that parents experience stress and anxiety because of the uncertainty of the disease and the suffering of their children.
Children in the study between the ages of 7-12 did not show any change in their anxiety or sense of well-being. However, adolescents between the ages of 13-18 years and the parents of hospitalised patients showed significant improvement.
“Teens reported that that they felt relaxed and calmer, and that it (yoga) was fun,” the authors wrote.
Parents found the yoga sessions were relaxing, allowed them to stretch their muscles and strengthen their bodies, and relieved stress.
Yoga lowers heart rate and blood pressure and improves circulation and oxygenation. It also improves muscle tone, circulation, pulmonary function, coordination and flexibility.
“Larger studies are needed to evaluate the influence of yoga on other distressing patient symptoms such as fatigue, sleep disturbance, pain and nauseam” authors add.
The findings are published in the September/October 2010 edition of Journal of Pediatric Oncology Nursing.