Sipping tea may help stave off heart disease, the leading cause of death in the United States. While few studies have tested tea's direct effects on heart health, the available research shows that people who drink more green tea and/or black tea may have a reduced heart disease risk.
Research on Tea for Heart Disease
In a study released in 2010, researchers found that participants who drank more than six cups of tea per day had a 36 percent reduced risk of heart disease (compared to those who drank less than one cup of tea daily). Study results also revealed that drinking three to six cups of tea each day was linked to a 45 percent lower risk of death from heart disease (compared to consumption of less than one cup per day). For the study, researchers surveyed 37,514 people about their tea-drinking habits, then followed them for 13 years in order to track incidences of heart disease and death.
A 2008 research review found "consistent data" that tea can improve function in the endothelium (the layer of cells lining the inside of blood vessels), which may aid in heart disease defense. The review also found that tea may help improve certain heart disease risk factors (such as blood pressure and inflammation), but that evidence for tea's effects on cholesterol is weak.
Role of Antioxidants?
Although scientists have yet to confirm how tea might fight heart disease, some research suggests that antioxidants may play a key role. Abundant in both green tea and black tea, antioxidants are natural substances thought to protect against oxidative stress (a destructive process linked to the development of heart disease). In a report published in 2008, for instance, scientists note that green tea's antioxidant and anti-inflammatory properties are thought to contribute to its cardiovascular benefits. And in a previous study of 66 patients with heart disease, researchers found that four weeks of black tea consumption (about 3.8 cups per day) reversed endothelial dysfunction (possibly due to the antioxidants' effects on blood vessel health).
Using Tea For Health Purposes
Although scientists have yet to prove that tea can prevent heart disease, regular tea consumption may offer some cardiovascular benefits. Before increasing your tea intake, however, it's important to consult your primary care provider to determine which dose might be appropriate for you. In some individuals, high doses of the caffeine found in tea may lead to adverse effects (such as increased heart rate and blood pressure, both of which may contribute to heart disease).
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