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Yoga: In Depth

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What’s the Bottom Line?

How much do we know about yoga?

Although much research has been done on the health effects of yoga, many of the studies have included only small numbers of people and have not been of high quality. Therefore, in most instances, we can only say that yoga has shown promise in helping to manage a particular health condition, not that it has been proven effective. Yoga is generally safe for healthy people when performed properly; individuals with health conditions should discuss their needs with their health care providers and the yoga instructor.

What do we know about the effectiveness of yoga?

  • National survey results from 2012 show that many people who practice yoga believe that it improves their general well-being, and there is beginning to be evidence that it actually may help with some aspects of wellness including stress management, balance, positive aspects of mental health, and promoting healthy eating and physical activity habits.
  • Yoga may help relieve low-back pain and neck pain.
  • There’s promising evidence that yoga may help people with some chronic diseases such as cancer, multiple sclerosis, and chronic obstructive pulmonary disease manage their symptoms and improve their quality of life.
  • Yoga may help people with diabetes control their blood sugar.
  • Growing evidence indicates that yoga may help women manage both physical and psychological symptoms of menopause.
  • Yoga may be helpful for anxiety or depressive symptoms associated with difficult life situations, but it has not been shown to help in managing anxiety disorders, clinical depression, or posttraumatic stress disorder.
  • Yoga may help people manage sleep problems.
  • Yoga may be helpful for people who are trying to quit smoking.
  • Yoga-based interventions may help overweight/obese people lose weight.

What do we know about the safety of yoga?

  • Yoga is generally considered a safe form of physical activity for healthy people when performed properly, under the guidance of a qualified instructor. However, as with other types of physical activity, injuries can occur. The most common injuries are sprains and strains. Serious injuries are rare. 
  • People with health conditions, older adults, and pregnant women may need to avoid or modify some yoga poses and practices. These individuals should discuss their specific needs with their health care providers and their yoga instructors.

About Yoga

Yoga is an ancient and complex practice, rooted in Indian philosophy, that originated several thousand years ago. Yoga began as a spiritual practice, but it has become popular as a way of promoting physical and mental well-being. Although classical yoga also includes other elements, yoga as practiced in the United States typically emphasizes physical postures (asanas), breathing techniques (pranayama), and meditation (dyana). Popular yoga styles such as iyengar, bikram, and hatha yoga focus on these elements. Several traditional yoga styles encourage daily practice with periodic days of rest, whereas others encourage individuals to develop schedules that fit their needs. 

The frequency and duration of yoga sessions vary depending on the condition being treated. In general, studies examining yoga as an intervention have included weekly or twice weekly 60- to 90-minute classes. For some studies, classes are shorter, but there are more classes per week. Classes can range from a single class followed by a home intervention to a weeklong retreat. Most studies encourage home practice.

Use of Yoga for Health in the United States

The 2017 National Health Interview Survey (NHIS) found that the use of yoga by U.S. adults increased significantly from 2012 (from 9.5 percent in 2012 to 14.3 percent in 2017). The percentage of U.S. children who used yoga more than doubled during this time (from 3.1 percent in 2012 to 8.4 percent in 2017).

The 2012 National Health Interview Survey (NHIS) has provided additional insights about the use of yoga in the United States, including the following:

  • Among adults who practiced yoga, 94 percent reported doing so for wellness-related reasons—such as general wellness/disease prevention or to improve energy—and 18 percent said they used yoga to treat a specific health condition. (The numbers add up to more than 100 percent because some people used yoga in both ways.)  
  • A large proportion of the adults who practiced yoga perceived benefits from its use. 
    • 86 percent said that it reduced stress. 
    • 59 percent said that it improved their sleep. 
    • 67 percent said that they felt better emotionally. 
    • 39 percent said that yoga made it easier to cope with health problems. 
    • 82 percent said that it improved their overall health and made them feel better. 
    • 63 percent said that it motivated them to exercise more regularly. 
    • 43 percent said that it motivated them to eat healthier.  
  • The most common health conditions for which people practiced yoga were back pain, stress, and arthritis.  
  • Only one-third of adults who practiced yoga told their health care providers about it.

What the Science Says About the Effectiveness of Yoga

Wellness

Although most American adults who practice yoga say that it improves wellness, only a small amount of research has been done on the actual effects of yoga on various aspects of wellness. Not all of the studies have been of high quality, and findings have not been completely consistent. Nevertheless, some preliminary research results suggest that yoga may help people manage stress, improve balance, improve positive aspects of mental health, and adopt healthy eating and physical activity habits.

  • Of 17 studies (involving 1,070 total participants) of yoga for stress management included in a recent review, 12 showed improvements in physical or psychological measures related to stress. 
  • Of 15 studies (involving 688 total participants) looking at the effect of yoga on balance in healthy people included in another review, 11 showed improvements in at least one outcome related to balance. 
  • In a recent review of 14 studies (involving 1,084 total participants) that assessed the effects of yoga on positive aspects of mental health, 10 studies found evidence of benefits, such as improvements in resilience or general mental well-being. 
  • A 2018 survey of young adults (involving 1,820 participants) showed that practicing yoga regularly was associated with better eating and physical activity habits, such as more servings of fruits and vegetables, fewer servings of sugar-sweetened beverages, and more hours of moderate-to-vigorous activity. Because this was a cross-sectional survey (people were studied on only one occasion rather than being observed over time), the results don’t necessarily show that yoga caused these better habits; it’s also possible that people with healthier habits are more likely to do yoga. However, interviews with 46 of the participants who practiced yoga indicated that they thought yoga supported healthier habits in various ways, such as through greater mindfulness, motivation to eat healthier and participate in other forms of activity in addition to yoga, and the influence of a health-minded yoga community.

Asthma

  • A 2016 review of 15 studies of yoga for asthma (involving 1,048 total participants) concluded that yoga probably leads to small improvements in quality of life and symptoms in people with asthma. 
  • Complementary health approaches such as yoga should never be used as a substitute for medical treatment for asthma.  
  • For more information, see the NCCIH fact sheet on asthma

Cancer Symptom Management

Yoga has shown promise as a way to help people manage some cancer symptoms and cancer treatment side effects and improve their quality of life.

  • In a 2018 evaluation of 138 studies on the use of yoga in patients with various types of cancer (involving 10,660 total participants), most of the studies found that yoga improved patients’ physical and psychological symptoms and quality of life.  
  • The amount of research on yoga for patients with each of the individual types of cancer is small, with one exception—breast cancer. A 2017 review of 24 studies in patients with breast cancer (involving 2,166 total participants) found moderate-quality evidence that yoga, when compared to no treatment, was helpful in improving health-related quality of life and reducing fatigue and sleep disturbances. Yoga was more helpful than educational interventions for reducing depression, anxiety, and fatigue in women with breast cancer, and it may have been as helpful as other forms of exercise for health-related quality of life and fatigue.  
  • For more information, see the NCCIH fact sheet on cancer.

Cardiovascular Disease Risk Factors

  • Stress and a sedentary lifestyle are major risk factors for cardiovascular disease. Because yoga involves exercise and may help reduce stress, it might help reduce risk. However, only small, short-term, low-quality studies have examined this topic. A 2014 review of 11 studies (involving 800 participants) provided some evidence that yoga may improve some risk factors, such as diastolic blood pressure (the bottom number in a blood pressure reading) and levels of high-density lipoprotein (HDL) cholesterol and triglycerides; however, these results should not be considered conclusive.
  • In a 2015 review of 17 studies (involving 1,310 participants) of yoga for hypertension (high blood pressure), a risk factor for cardiovascular disease, yoga reduced systolic blood pressure (the top number in a blood pressure reading) in 11 studies and diastolic blood pressure or nighttime blood pressure in 8. 
  • For more information, see the NCCIH webpage on cardiovascular disease

Chronic Obstructive Pulmonary Disease (COPD)

  • A 2018 analysis of 10 studies (involving 502 total participants) found evidence that yoga can improve physical ability (such as the capacity to walk a defined distance in a defined time), lung function, and quality of life in people with COPD. Therefore, yoga could be a helpful addition to rehabilitation programs for people with this condition.

Diabetes

  • A 2017 evaluation of 23 studies with 2,473 participants showed that participating in yoga programs was associated with better blood sugar control in people with type 2 diabetes, at least on a short-term basis. 

Irritable Bowel Syndrome (IBS)

  • A 2016 review of 6 studies (involving 273 total participants) of yoga in people with IBS found some evidence that yoga could decrease IBS symptoms and severity, as well as anxiety. However, because the studies used different methods that couldn’t be compared easily and because of the risk that the findings might be biased, no definite conclusions about the effects of yoga could be reached.  
  • For more information, see the NCCIH fact sheet on IBS.

Menopause Symptoms

  • A 2018 evaluation of 13 studies (involving 1,306 total participants) of yoga for menopause symptoms found that yoga reduced physical symptoms, such as hot flashes, and psychological symptoms, in comparison with no treatment. Six years earlier, a similar evaluation of the evidence found benefits only for psychological symptoms, but newer research indicates that yoga is helpful for physical symptoms as well. Yoga seems to be at least as effective as other types of exercise in relieving menopause symptoms. 
  • For more information, see the NCCIH fact sheet on menopause symptoms.

Mental Health Conditions

There’s some evidence that yoga might be helpful for anxiety or depression symptoms, but it primarily comes from studies of people who didn’t have diagnosed mental health conditions. Studies in people who had been diagnosed with anxiety disorders, depression, or posttraumatic stress disorder (PTSD) have had less favorable results.

  • In a 2013 review of 23 studies (involving 1,722 participants) of yoga for anxiety associated with various life situations (such as medical conditions or stressful educational programs), yoga seemed to be helpful in some instances but not in others. In general, results were more favorable for interventions that included at least 10 yoga sessions. Overall, though, the studies were of medium to poor quality, so definite conclusions about yoga’s effectiveness could not be reached.
  • A 2018 review of 8 studies of yoga for anxiety (involving 319 participants with anxiety disorders or elevated levels of anxiety), found evidence that yoga might have short-term benefits in reducing the intensity of anxiety. However, when only people with diagnosed anxiety disorders were included in the analysis, no beneficial effects of yoga were found.
  • In a recent review of 23 studies (involving 1,272 participants) in people with depressive symptoms (although not necessarily diagnosed with depression), yoga was helpful in reducing symptoms in 14 of the studies.
  • A 2017 review of 7 studies (involving 240 participants) of yoga interventions in people who had been diagnosed with depression found some evidence of beneficial effects but the reviewers judged the evidence to be insufficient to justify recommending yoga for people with this condition. Problems included the small number of people studied and an inability to compare benefits with risks because of inadequate information on the safety of yoga for people with depression.
  • A 2017 evaluation of 7 studies (involving 284 participants) of yoga for people with PTSD found only low-quality evidence of a possible beneficial effect.
  • For more information, see the NCCIH Mental Health webpage.

Multiple Sclerosis

  • Only a few studies have looked at the effects of yoga in people with multiple sclerosis. A 2014 review of 7 studies (involving 670 participants) found evidence that yoga had short-term benefits on fatigue and mood in people with multiple sclerosis, but it didn’t affect muscle function, cognitive function, or quality of life. The effects of yoga on fatigue were similar to those of exercise.
  • For more information, see the NCCIH Multiple Sclerosis webpage.

Pain Conditions 

  • A 2018 report by the Agency for Healthcare Research and Quality evaluated 8 trials of yoga for low-back pain (involving 1,466 total participants) and found that yoga improved pain and function both in the short term (1 to 6 months) and intermediate term (6 to 12 months). The effects of yoga were similar to those of exercise. Yoga is among the options that the American College of Physicians recommended for initial nondrug therapy for chronic low-back pain in a 2017 clinical practice guideline. 
  • A 2017 review of 3 studies (involving 188 total participants) found that yoga had short-term benefits for both the intensity of neck pain and disability related to neck pain.
  • Very little research has been done on yoga for headaches. A 2015 attempt to review the research on this topic found only one study with 72 participants that could be evaluated. That study had favorable results, with decreases in headache intensity and frequency, but one study is not much evidence.
  • Perhaps surprisingly, since arthritis is one of the most common conditions for which people use yoga, there hasn’t been much research on yoga for osteoarthritis, rheumatoid arthritis, or other conditions associated with joint pain. A 2013 evaluation found only 8 studies that could be evaluated: 3 on osteoarthritis (involving 304 participants), 2 on rheumatoid arthritis (involving 110 participants), 2 on fibromyalgia (involving 96 participants), and 1 on carpal tunnel syndrome (involving 51 participants). The studies showed weak evidence of a possible benefit for pain in all of the conditions except carpal tunnel syndrome.
  • For more information, see the NCCIH Pain webpage.

Sleep Problems

  • Of 10 studies of yoga for sleep disturbances associated with cancer treatment, 7 showed significant improvements in various aspects of sleep, according to a 2018 review.
  • A 2017 review of studies in older adults found evidence that yoga can improve several aspects of sleep in this population, including the time taken to fall asleep, the duration of sleep, and the feeling of being rested in the morning.
  • Individual studies have also suggested that yoga may be helpful for sleep in other populations, including people with arthritis, pregnant women, and women with menopause symptoms.

Smoking Cessation

  • A 2014 report evaluated 10 studies (484 participants) in which yoga-based interventions were tested as an aid to smoking cessation. In most of the studies, yoga reduced cravings and the number of cigarettes smoked.

Weight Control

  • In 2013, NCCIH-supported researchers examined 17 yoga-based interventions for weight control to try to identify factors associated with the greatest success. They found that factors associated with greater effectiveness included longer and more frequent yoga sessions, a longer duration of the overall program, a yoga-based dietary component, a residential component (such as a full weekend to start the program), inclusion of a larger number of elements of yoga, and home practice.
  • A 2016 analysis of 10 studies of yoga in which all participants were overweight or obese found that practicing yoga was associated with reduced body mass index (BMI; a measure of body fat based on height and weight).

What the Science Says About the Safety and Side Effects of Yoga

  • Yoga is generally considered a safe form of physical activity for healthy people when performed properly, under the guidance of a qualified instructor. However, as with other forms of physical activity, injuries can occur. The most common injuries are sprains and strains. Serious injuries are rare. The risk of injury associated with yoga is lower than that for higher impact sports activities. 
  • People who are just starting to practice yoga should avoid extreme practices such as headstands, shoulder stands, the lotus position, and forceful breathing. 
  • Bikram yoga (“hot yoga”) has special risks related to overheating and dehydration.  
  • People with health conditions, older adults, and pregnant women may need to avoid or modify some yoga poses and practices and should discuss their individual needs with their health care providers and the yoga instructor. Different situations call for different restrictions. For example, people with conditions that weaken their bones should avoid forceful forms of yoga, and people with glaucoma should avoid upside-down positions.

Yoga in Different Population Subgroups

Much of the research on yoga in the United States has been conducted in populations similar to those among whom yoga is most popular—that is, predominantly female, non-Hispanic white, well-educated people with relatively high incomes. Other people—particularly members of minority groups and those with lower incomes—have been underrepresented in yoga studies.

Different groups of people may have different experiences related to yoga. For example:

  • In one survey, middle-aged people were more likely to be motivated to practice yoga to increase muscle strength or lose weight, while older adults were more likely to be motivated by age-related chronic health issues.
  • National survey data indicate that “lack of knowledge” is more commonly reported as a reason for not practicing yoga among people with lower educational attainment than those with greater education, both in the general population and among people with low-back pain.
  • A study found evidence for differences between men and women in the effects of specific yoga poses on muscles.
  • A study in veterans found preliminary evidence that women might benefit more than men from yoga interventions for chronic back pain.
  • Data from emergency departments indicate that the rate of yoga-related injuries is higher in people age 65 and older than in younger adults.

Research Funded by the National Center for Complementary and Integrative Health (NCCIH) 

NCCIH-sponsored studies are investigating the effects of yoga on a variety of conditions including: 

  • Generalized anxiety disorder 
  • Sleep disturbance and fatigue in cancer patients receiving chemotherapy 
  • Depression in adolescents 
  • Chronic pain in veterans.

More To Consider

  • Don’t use yoga to postpone seeing a health care provider about a medical problem. 
  • Ask about the training and experience of the yoga instructor you’re considering. 
  • Take charge of your health—talk with your health care providers about any complementary health approaches you use. Together, you can make shared, well-informed decisions.

For More Information

NCCIH Clearinghouse

The NCCIH Clearinghouse provides information on NCCIH and complementary and integrative health approaches, including publications and searches of Federal databases of scientific and medical literature. The Clearinghouse does not provide medical advice, treatment recommendations, or referrals to practitioners.

Toll-free in the U.S.: 
1-888-644-6226
TTY (for deaf and hard-of-hearing callers): 
1-866-464-3615

PubMed®

A service of the National Library of Medicine, PubMed® contains publication information and (in most cases) brief summaries of articles from scientific and medical journals. For guidance from NCCIH on using PubMed, see How To Find Information About Complementary Health Approaches on PubMed.

NIH National Library of Medicine's MedlinePlus

To provide resources that help answer health questions, MedlinePlus brings together authoritative information from the National Institutes of Health as well as other Government agencies and health-related organizations.

Web site: www.medlineplus.gov

Key References

All Other References

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Acknowledgments

NCCIH thanks Inna Belfer, M.D., Ph.D., and David Shurtleff, Ph.D., NCCIH, for their review of the 2018 update of this publication.

This publication is not copyrighted and is in the public domain. Duplication is encouraged.

NCCIH has provided this material for your information. It is not intended to substitute for the medical expertise and advice of your health care provider(s). We encourage you to discuss any decisions about treatment or care with your health care provider. The mention of any product, service, or therapy is not an endorsement by NCCIH.

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NCCIH Pub No.: 
D472
Last Updated: 
October 2018

This page last modified November 08, 2018