What Yoga Does to the Body's Stress Chemistry

This meta-analysis pooled forty-two randomised trials that measured what yoga does to the body's stress physiology, comparing yoga against an active alternative rather than simply doing nothing. The pattern was consistent: practices including yoga postures were associated with lower evening and waking cortisol, the main stress hormone, along with reduced blood pressure and resting heart rate, improved heart rate variability, and healthier blood sugar and cholesterol. Together these point to a calmer sympathetic nervous system and a better-regulated stress axis, the physiological signature of a body less stuck in high alert. The honest caveat is variety: the trials differed considerably in style, dose and population, so the average conceals a wide range, and much of the strongest data came from clinical groups. Still, this is stress relief you can measure in the blood, not only report in a questionnaire. For a woman whose stress has become physical, showing up as tension, disturbed sleep or a racing pulse, it frames yoga as a credible way to work on the biology of stress from the inside.