What is yoga? Is there any evidence of health benefits? Are there any health risks?
What is yoga?
Yoga is a form of mind-body fitness. It involves a combination of muscular activity and an internally directed mindful focus on awareness of the self, the breath and energy. It integrates physical, mental and spiritual components to potentially improve aspects of health. For instance, a review of the evidence, published in 2013, suggested it appears to help people manage stress, while a 2015 review suggested ways yoga affects the way our bodies function, which may explain why it has been reported as reducing the symptoms of anxiety and depression.
Some people practise yoga mainly as a form of exercise (for instance as an alternative to Pilates), some mainly for what they perceive as mental or spiritual benefits and some for a combination of the two.
It is classified by the US National Institutes of Health as a form of Complementaryand Alternative Medicine.
A useful form of exercise?
The NHS’ verdict is that most studies suggest yoga is a safe and effective way to increase physical activity, especially strength, flexibility and balance. The NHS also advises that yoga can reduce the risk of falls, by strengthening the lower body.
Yoga doesn’t count towards the 150 minutes of moderate-intensity aerobic activity per week, set out in UK government guidelines. However, it does count as a strengthening exercise and at least two sessions a week will help you meet the guidelines on muscle-strengthening activities.
What are the different types of yoga?
There are different types of yoga and variations on those types, including
- Hatha – the most popular form in the West. It focuses on physical techniques, including disciplines, postures, gestures and breathing, as well as on meditation.
- Bhakti Yoga or Yoga of devotion – a spiritual or devotional approach which doesn’t involve such extensive yogic practices. This is the path most followed in India
- Raja Yoga or Yoga of Self-Control; Jnana Yoga or Yoga of the Mind; Karma Yoga or Yoga of Service; and Tantra Yoga or Yoga of Rituals.
Another popular form of yoga currently is Bikram – 26 poses in a heated room.
Can it help lower back pain?
Yes, according to a systematic review of the evidence published in 2013. A 2017 review was cautiously positive. It concluded there was low-to-moderate certainty evidence that yoga results in small to moderate improvements in back -related functions, as measured after 3 months and 6 months.
Can it help manage depression?
In a short, small scale pilot study reported in 2013, family dementia care givers practiced yogic meditation daily. This led to improved mental and cognitive functioning and lower levels of depressive symptoms. There was also an increase in telomerase activity suggesting reduction in stress–induced cellular ageing. A larger review found moderate evidence that yoga had positive short term effects for people with depression. A 2017 review, focusing on yoga as an additional treatment for major depression, was more cautious in its conclusions. It found some evidence of positive effects but was concerned about the quality of the research undertaken, so considered that better quality research was needed before it could make recommendations.
Can it help breast cancer patients?
One trial, published in 2014, observed 200 breast cancer survivors who had not practiced yoga before. The half who started to practice yoga reported less fatigue and higher levels of vitality three months after treatment had ended. Blood tests before and after the trial showed that three markers for inflammation (which has long been associated with the development of cancer) were lower by 10 to 15 percent. A review of studies into yoga for breast cancer patients, published in 2017, concluded there was moderate quality evidence that yoga helped improve health related quality of life and reduce fatigue and sleep disturbances.
Can it help prevent or manage diabetes?
A short, small scale study published in 2008 suggested, by measuring biological markers, that yoga can improve levels of glucose and insulin in patients with diabetes. A 2017 review of the evidence concluded that yoga was likely to help patients with type 2 diabetes by improving glycemic outcomes and other risk factors. The benefits of yoga for people with diabetes is also a topic covered by Diabetes UK.
Can the research on yoga be trusted?
Many clinical trials have been designed to assess its therapeutic effects and benefits. While these trials are often promising, questions are frequently asked about the way the research was conducted. The verdict is often that more research is needed. An example is a 2014 review of the effectiveness of yoga as a treatment for hypertension – which concluded that the evidence was encouraging but inconclusive.
Is yoga safe?
Problems can occasionally arise, A 2013 review of the evidence advised that reported problems included sprains and strains, and problems with spine, shoulder, joints and eyes - although the number of cases was very small. That’s why the advice is usually:
- Ask a trusted source (such as your health care provider or a nearby hospital) to recommend a yoga practitioner.
- Ask about the physical demands of the type of yoga in which you are interested and inform your yoga instructor about any medical issues.
- If you’re a beginner, avoid extreme practices such as headstand, lotus position and forceful breathing.
Conclusions
- Yoga may help people with a range of conditions, especially anxiety, stress, lower back pain and possibly depression. It seems to help maintain balance when you're older or after a stroke. It may also help patients with diabetes and patients with breast cancer.
- Yoga is generally safe but, as with any exercise, if you have health issues you are advised to check with your doctor first before starting a programme.
- Scientific studies on the potential benefit of yoga have increased but more good quality research is still very much needed.
Reviewed and updated by Karen Rollins, November 2017 Next review date, October 2021