By: Matthew (Ted Ballwin)

Yoga is increasing in popularity. Once derided as useless, the practice of stretching, breathing and challenging your body's flexibility and stamina has become more widespread, as has information on its health benefits.

One of the most interesting areas of information to come out of relevant studies is the reduction in stress. Historically stress is a major cause for employee sick time, heart disease, and family breakdown and is a major 'silent killer', as a contributing factor to cardiovascular disorder (CVD). Stress can be seen as a symptomatic response to the things going on around us, which are physical and mental responses to our situations. Tearful or angry outbursts by overextended people, metabolism problems, increased skin conductivity (a measure of response to stress), problems with distressing via exercise because of tenseness or muscle strains, and high blood pressure, are all areas where yoga can help. Yoga lowers your stress levels and has surprising other health benefits, which, in their way, reduce the risk of cardiovascular disease.

Why is it important to lower stress?

A major factor in cardiovascular disorders is high blood pressure, which is treated with beta blockers and other medication. High blood pressure is a leading cause of heart attacks, and in some risk factor lists it ranks above high cholesterol, poor diet or diabetes. When left unchecked, high blood pressure can cause embolism, stroke or heart failure.

Lowering the stress of someone with high blood pressure is an incredibly important element of their regimen, which is why a recent overview of 70 yoga clinical studies from the past 35 years may hold the breakthrough to supporting people into choosing a low cost, no side effect alternative to their current treatment plans. Yoga gives them the opportunity to increase body flexibility, posture and relaxation, and has some interesting separate health benefits.

Scientific observations of using Yoga to lower stress

The observations in the study showed a manifold drop in stress, obesity, blood pressure, free radicals, bad cholesterol and an increase in antioxidants, markers of good cardio-respiratory function, breathing regulation and more. All of these show promise in fighting heart disease and stress related problems. Of the 51 studies, the following data was collated:

• The research by Dr Innes identified a core set of 42 studies that investigated yoga in relation to cardio-vagal response; specifically, the vagus nerve and its ability to lower the heart rate. These studies showed that those who practiced yoga for a long period time had significant reduction in cortisol concentrations and respiratory and heart rates. Cortisol is a chemical that the body produces in response to anxiety and stress, amongst a set of other 'stress' related chemicals, and is believed to suppress immune response and cause an increase in both blood pressure and blood sugar levels.

• Skin conductance was reduced and cardiovascular response to stress in general was far more favorable. Renin, an enzyme that controls blood pressure, was reduced as well.

• Changes were also noted in adrenal gland secretions, which in turn lead to a drop in blood pressure as these 'fight or flight' chemicals were reduced. Overall, the heart and respiratory rate at rest and after exercise were more favorable in all groups involved in these studies, whether healthy or hypertensive, adult or child.

• Out of 37 studies, 28 reported improvement in blood pressure. Specifically, healthy adults and those with hypertension who practiced Raja yoga meditation exhibited reduced diastolic pressure.

• Mental and physical wellbeing and the chemicals associated with them were increased, as was the body's production of antioxidants, which eliminate free radicals in the body and protect the skin.

• Sleep, posture and energy levels also improved, which in the chronically ill or disabled is a good sign, as yoga is a fairly inclusive exercise regimen - anyone can take part, with supervision, and join in at one of the levels. Yoga creates a feeling of well being that counters the effects of stress, which in turn supports the lowering of blood pressure. Increased and appropriate sleep also supports a better stress response as you are less likely to feel overwhelmed or under pressure if you are clear headed, and this by itself lowers stress.

All of these elements feed from the positive changes in the cardio-vagal system to your mental and physical responses, which in turn supports the lowering and mitigation of risk factors associated with cardiovascular disease. But it doesn't end there.

Physical signs that Yoga helps the body

Studies have suggested that yoga, in all forms, supports the lowering of bad cholesterol and increases the good cholesterol, while lowering triglyceride levels. Triglycerides are a specific molecule contained in animal and vegetable fats. Unused triglycerides are stored as fat. Historically we are consuming far more of these than any other time in recorded existence, which is why many people believe dietary issues need to be addressed at the forefront of ending heart disease. Ideally an adult should have less than 100 mg/dL of LDL's, which is also referred to as bad cholesterol , and more than 50mg/dL of HDLs, known as good cholesterol . Yoga appears to reduce total cholesterol by up to 25%. Specifically, it lowers triglycerides by up to almost 30% and decreases LDL by up to 26%.

This in turn leads to weight loss and better body composition. It is common sense that less weight means less pressure on joints and less stress on your heart. Moreover, posture-improving routines can increase blood flow. Eighteen studies from six countries focused on these elements and the results suggested that there was an improvement in both body composition and posture after short and long term yoga exercises, plus between 1.5% and 13.6% weight loss. These studies were far reaching, covering those with and without CVD factors and diabetes.

What this means for your health?

While the studies are still waiting conclusive controlled testing, this information, which has been collected over a period of 34 years, clearly shows that yoga has considerable health benefits. With no barriers to entry, no known side effects and with a reputable instructor, it cannot harm anyone's health. In fact, with the myriad of evidence-based results collected in these studies there is no reason not to recommend yoga to anyone who is struggling with traditional exercise, stress, or needs to lose weight. Very few other exercises combine low cost, low entry barrier and high results as yoga does. While the final studies are underway into exactly how yoga affects our health and wellness, there is no reason not to give it a try yourself.