A review of 47 studies showed a 5 to 10 per cent reduction in anxiety symptoms and a 10 to 20 per cent improvement in depression in individuals who meditated compared with placebo groups, according to research published in JAMA Internal Medicine.

The analysis also suggested that meditation eased pain, though it was not clear which types of pain benefit most.

The findings may support the use of ‘‘mindfulness’’ meditation as a way to moderate the need for medications to treat anxiety and depression, said Allan Goroll, a professor of medicine at Massachusetts General Hospital, in an accompanying editorial. Mindfulness meditation is a form practised for 30 to 40 minutes a day that teaches a person how to become more aware of one’s thoughts, breathing and emotions.

‘‘The findings of such research should be the subject of conversations that need to begin in every examination room and extend to engage the media, who play a key role in determining patient attitudes toward health care and the demand for services,’’ Goroll wrote.

Researchers looked at 47 trials through June of 3515 people. The studies included meditation and evaluated an assortment of mental and physical health issues, including depression, anxiety, insomnia, heart disease, chronic pain and stress. The analysis was funded by the US Agency for Healthcare Research and Quality.

Patients who underwent about an eight-week training program for mindfulness meditation showed improvement in symptoms of anxiety, depression and pain. Most of the patients had not been diagnosed with clinical anxiety or depression. Those reductions in symptoms were similar to the effects that other studies have found for the use of antidepressants in similar populations, researchers said.

Madhav Goyal, an assistant professor in the Division of General Internal Medicine at Johns Hopkins University in Baltimore and the study’s lead author, said the researchers did not know why meditation may work at relieving depression and anxiety, though it could be that people who learn meditation reduce their reaction to negative emotions or symptoms and that lowers the effects that those negative emotions have on them.

‘‘Clinicians should be prepared to talk with their patients about the role that meditation programs could have in addressing psychological stress, particularly when symptoms are mild,’’ he said.

Still, more studies that were larger were needed to better understand who was helped the most by meditation programs, Goyal said.

‘‘Our review suggests that there is moderate evidence for a small but consistent benefit for anxiety, depression and chronic pain,’’ he said.

‘‘There is no known major harm from meditating, and meditation doesn’t come with any known side effects.

‘‘One can also practise meditation along with other treatments one is already receiving.’’

There was little evidence in the analysis that meditation improved quality of life or stress and not enough information to show if other areas, including attention, substance abuse, sleep and weight, were improved by the meditation, the authors said.

‘‘We should keep foremost in our mind that meditation was never conceived of as a treatment for any health problem,’’ Goyal said.

‘‘Rather, it is a path one travels on to increase our awareness and gain insight into our lives.

‘‘The best reason to meditate is to increase insight into one’s life which is probably good for everyone.’’AP