20 Ways Deep Breathing Reduces Cortisol Instantly
17. Improving Respiratory Health (Lung Capacity & Efficiency)

While reducing cortisol is key, deep breathing also directly benefits lung health. By engaging the diaphragm, it encourages full lung expansion, improving oxygen exchange efficiency and overall lung capacity. This means your body becomes more efficient at taking in oxygen and expelling carbon dioxide, reducing the "work" of breathing. Better respiratory function means less physiological stress on your body, contributing to a more relaxed state and implicitly supporting lower cortisol levels.