The environment is often cited as an important factor influencing the health status of individuals. This includes characteristics of the natural environment, the built environment and the social environment. Factors such as clean water and air, adequate housing, and safe communities and roads all have been found to contribute to good health, especially to the health of infants and children.[18][29] Some studies have shown that a lack of neighborhood recreational spaces including natural environment leads to lower levels of personal satisfaction and higher levels of obesity, linked to lower overall health and well being.[30] This suggests that the positive health benefits of natural space in urban neighborhoods should be taken into account in public policy and land use.

The first known appearance of the word "yoga", with the same meaning as the modern term, is in the Katha Upanishad,[10][95] probably composed between the fifth and third century BCE,[96][97] where it is defined as the steady control of the senses, which along with cessation of mental activity, leading to a supreme state.[67][note 13] Katha Upanishad integrates the monism of early Upanishads with concepts of samkhya and yoga. It defines various levels of existence according to their proximity to the innermost being Ātman. Yoga is therefore seen as a process of interiorization or ascent of consciousness.[99][100] It is the earliest literary work that highlights the fundamentals of yoga. White states:
Modern yoga was created in what has been called the Modern Yoga Renaissance[213] by the blending of Western styles of gymnastics with postures from Haṭha yoga in India in the 20th century, pioneered by Shri Yogendra and Swami Kuvalayananda.[214] Before 1900 there were few standing poses in Haṭha yoga. The flowing sequences of salute to the sun, Surya Namaskar, were pioneered by the Rajah of Aundh, Bhawanrao Shrinivasrao Pant Pratinidhi, in the 1920s.[215] Many standing poses used in gymnastics were incorporated into yoga by Krishnamacharya in Mysore from the 1930s to the 1950s.[216] Several of his students went on to found influential schools of yoga: Pattabhi Jois created Ashtanga Vinyasa Yoga,[217] which in turn led to Power Yoga;[218] B. K. S. Iyengar created Iyengar Yoga, and systematised the canon of asanas in his 1966 book Light on Yoga;[219] Indra Devi taught yoga to many film stars in Hollywood; and Krishnamacharya's son T. K. V. Desikachar founded the Krishnamacharya Yoga Mandalam in Chennai.[220][221][222] Other major schools founded in the 20th century include Bikram Choudhury's Bikram Yoga and Swami Sivananda of Rishikesh's Sivananda Vedanta Schools of Yoga. Modern yoga spread across America and Europe, and then the rest of the world.[223][224]
These meditations were seen as being supported by the other elements of the eightfold path, such as the practice of ethics, right exertion, sense restraint and right view.[244] Two mental qualities are said to be indispensable for yogic practice in Buddhism, samatha (calm, stability) and vipassanā (insight, clear seeing).[245] Samatha is the quality of a stable, relaxed and calm mind. It is also associated with samadhi (mental unification, focus) and dhyana (a state of meditative absorption). Vipassanā meanwhile, is a kind of insight or penetrative understanding into the true nature of phenomena. It is also defined as "seeing things as they truly are" (yathābhūtaṃ darśanam). The true nature of things is defined and explained in different ways, but an important and unique feature of classical Buddhism is its understanding of all phenomena (dhammas) as being empty of a self (atman) or inherent essence, a doctrine termed Anatta ("not-self") and Śūnyatā (emptiness).[246][247] This is in sharp contrast with most other Indian traditions, whose goals are founded either on the idea of an individual soul (atman, jiva, purusha) or a universal monistic consciousness ( Brahman). Vipassanā also requires an understanding of suffering or dukkha (and thus the four noble truths), impermanence (anicca) and interdependent origination.
The tantra yoga practices include asanas and breathing exercises. The Nyingma tradition practices Yantra yoga (Tib. "Trul khor"), a discipline that includes breath work (or pranayama), meditative contemplation and other exercises.[190] In the Nyingma tradition, the path of meditation practice is divided into further stages,[191] such as Kriya yoga, Upa yoga, Yoga yana, Mahā yoga, Anu yoga and Ati yoga.[192] The Sarma traditions also include Kriya, Upa (called "Charya"), and Yoga, with the Anuttara yoga class substituting for Mahayoga and Atiyoga.[193]

During the period between the Mauryan and the Gupta eras (c. 200 BCE–500 CE) the Indic traditions of Hinduism, Buddhism and Jainism were taking form and coherent systems of yoga began to emerge.[50] This period witnessed many new texts from these traditions discussing and systematically compiling yoga methods and practices. Some key works of this era include the Yoga Sūtras of Patañjali, the Yoga-Yājñavalkya, the Yogācārabhūmi-Śāstra and the Visuddhimagga.
Since the late 1970s, the federal Healthy People Initiative has been a visible component of the United States’ approach to improving population health.[11][12] In each decade, a new version of Healthy People is issued,[13] featuring updated goals and identifying topic areas and quantifiable objectives for health improvement during the succeeding ten years, with assessment at that point of progress or lack thereof. Progress has been limited to many objectives, leading to concerns about the effectiveness of Healthy People in shaping outcomes in the context of a decentralized and uncoordinated US health system. Healthy People 2020 gives more prominence to health promotion and preventive approaches and adds a substantive focus on the importance of addressing social determinants of health. A new expanded digital interface facilitates use and dissemination rather than bulky printed books as produced in the past. The impact of these changes to Healthy People will be determined in the coming years.[14]
As chronic obstructive pulmonary disease (COPD) advances, about 35% of patients experience severe weight loss called pulmonary cachexia, including diminished muscle mass.[31] Around 25% experience moderate to severe weight loss, and most others have some weight loss.[31] Greater weight loss is associated with poorer prognosis.[31] Theories about contributing factors include appetite loss related to reduced activity, additional energy required for breathing, and the difficulty of eating with dyspnea (labored breathing).[31]
"When going out for fast food, I used to get the large-size value meal. Now, I satisfy a craving by ordering just one item: a small order of fries or a six-piece box of chicken nuggets. So far, I've shaved off 16 pounds in seven weeks, and I'm on track to being thinner than my high school self for my 10-year reunion later this year." —Miranda Jarrell, Birmingham, AL