Harvard Study Finds Daily Yoga Reduces Cortisol Levels by 30% in...

A 12-week randomised controlled trial conducted by Harvard T.H. Chan School of Public Health in collaboration with India National Institute of Mental Health and Neurosciences confirmed that adults who practised Hatha yoga for 45 minutes daily experienced a 30% reduction in salivary cortisol levels — the primary biological marker of chronic stress — compared to an active control group performing equivalent-intensity aerobic exercise. Participants in the yoga group also showed significantly improved heart rate variability, a 22% reduction in self-reported anxiety scores, and improved sleep quality as measured by polysomnography. The study enrolled 850 adults with clinically elevated occupational stress in Bengaluru, Boston, and London. WHO has cited the findings in an updated evidence review on mind-body practices for stress-related disorders. India Ministry of AYUSH is funding a larger 5,000-participant replication study across 10 countries.