Yoga for preventive healthcare is increasingly supported by scientific evidence, says AIIMS cardiologist Dr Ambuj Roy, citing major clinical trials that show benefits in heart attack recovery, blood pressure control and cardiovascular risk reduction.Every year on International Yoga Day, millions roll out their mats, celebrating a practice that has been part of India’s civilizational heritage for millennia. Yet the most important development of yoga for us in academia is happening beyond parks or stadiums. It is happening in research laboratories, clinical trials and medical journals.Yoga is steadily moving from a belief system to an evidence-based health intervention. The numbers tell a compelling story. Nearly 90 per cent of all scientific publications on yoga in medical literature have appeared in the last two decades. In fact, this has accelerated further in the last decade, with the number of yoga-related clinical trials reported in PubMed (the leading biomedical search engine) more than doubling in the most recent decade compared with the preceding ten years.This transition is particularly important in my field of cardiovascular medicine, where claims are scrutinized rigorously and only interventions supported by evidence find a place in clinical practice. Today, that evidence is beginning to emerge and become mainstream. One of the landmark studies in this field was the Indian Council of Medical Research-funded trial by our Yoga-CaRe group of authors, published in the Journal of the American College of Cardiology in 2020. Conducted across 24 centres in India and among nearly 4,000 patients recovering from heart attacks, it remains the largest randomised clinical trial ever undertaken on yoga-based cardiac rehabilitation.It found that patients who participated in a structured yoga-based rehabilitation programme reported significantly better health status and earlier return to normal daily activities following a heart attack. In fact, among practitioners who attended 75% or more of yoga sessions, there were 40% fewer adverse cardiovascular outcomes. The Yoga-CaRe trial was important not merely for its findings but also for demonstrating that yoga can be evaluated using the same rigorous standards applied to medicines and medical devices.More recently, CaReMATCH, an analysis of several cardiac rehabilitation trials, showed that yoga was as beneficial as conventional cardiac rehabilitation in improving quality of life and preventing recurrent hospitalizations by 30%. This has important implications for India, since the availability and acceptability of standard cardiac rehabilitation with multiple instruments and gadgets is limited and expensive, while yoga is culturally acceptable and readily available and affordable.A yoga-based rehabilitation model can extend the reach of cardiovascular care far beyond tertiary hospitals into smaller cities and rural communities. Research suggests that yoga works by improving autonomic balance (equilibrium between the sympathetic fight-or-flight and the parasympathetic rest-and-digest systems) enhancing heart-rate variability (the natural fluctuation in the exact time intervals between consecutive heartbeats and an indicator of how well your body adapts to stress and recovers from exertion) reducing stress-related hormonal activation, and improving psychological well-being. These mechanisms are key to cardiovascular health.Evidence for yoga is emerging not only in cardiac rehabilitation but also in preventive cardiovascular health. A growing body of research suggests that regular yoga practice can improve blood pressure, body weight, lipid levels and, importantly, quality of life. A pooled analysis of 49 trials found that yoga produced average reductions of 5 mmHg in systolic and 3 mmHg in diastolic blood pressure. Such reductions can lead to 25% and 20% lowering in the risk of brain and heart attack, respectively. The public health implications of this can be profound. Even modest improvements in these risk factors can translate into large reductions in cardiovascular disease and other non-communicable conditions, including disorders affecting brain health, kidney disease and bone health, when adopted across large populations.Story continues below this adAlso Read | International Yoga Day: Iconic yoga retreats around the worldBeyond disease prevention, yoga promotes positive health and has been shown to improve physical fitness, mental well-being, emotional resilience, sleep quality, and healthy aging—outcomes that are increasingly recognized as important components of overall health.The next step is to expand access to yoga while systematically measuring its impact on health outcomes. Doing so will help generate the evidence needed to guide policy and maximize yoga’s contribution to public health. Positive results should lead to its systematic implementation through the extensive network of Ayushman Aarogya Mandirs as a proactive health policy.The real story of yoga in the 21st century is, therefore, not one of ancient wisdom competing with modern science. It is one of ancient wisdom being examined, tested, and, where justified, validated by modern science. India has long exported yoga as culture. The moment has come to export it as evidence-based therapy.(The author is Professor of Cardiology, AIIMS, New Delhi)