Researchers say practising it can control stress and improve the wellbeing of women having radiation treatment.
Simple stretching exercises were able to lessen fatigue, the study showed.
But â€“ when stretching was combined with the breathing, meditation and relaxation techniques used in yoga â€“ breast cancer patients also felt healthier and more relaxed.
Lorenzo Cohen, a professor who led the research at the University of Texas, said that combining mind and body practices had â€˜tremendous potentialâ€™.
The study, which was reported in the Journal of Clinical Oncology, split 191 women with breast cancer into three groups: yoga, simple stretching and neither.
Women who practised yoga had the steepest fall in their cortisol levels, suggesting yoga helped regulate the stress hormone.
Dr Cohen said: ‘Combining mind and body practices that are part of yoga clearly have tremendous potential to help patients manage the psycho-social and physical difficulties associated with treatment and life after cancer, beyond the benefits of simple stretching.’
To conduct the study, 191 women with breast cancer were split into three groups – yoga; simple stretching; or no instruction in yoga or stretching.
Participants in the yoga and stretching groups attended sessions specifically tailored to breast cancer patients for one-hour, three days a week throughout their six weeks of radiation treatment.