Green tea (Camellia sinensis) is one of the most healthy and popular beverages, and provides proven benefits against many diseases. Green tea has been shown to help prevent cancer, fights metabolic syndrome, and can help lower inflammation.
A new study shows that green tea confers significant cardiovascular benefits. Cardiovascular diseases include cerebrovascular disease, coronary heart disease, and peripheral arterial diseases. The links between green tea consumption, cardiovascular disease (CVD), and ischemic related diseases were examined, and included 9 studies and 259,267 individuals. The results showed that green tea consumption was significantly linked with lower risk of CVD, stroke risk, cerebral infarction risk, intracerebral hemorrhage, myocardial infarction, and lowers low-density lipoprotein (LDL) cholesterol (the bad cholesterol).
The study showed dose-dependent effects of green tea, and those who never consumed green tea had higher CVD risk compared to those who consumed <1 cup/day. Those who drank 1–3 cups/day had a significantly reduced risk of myocardial infarction compared to those who drank <1 cup/day, and subjects that consumed ≥4 cups/day also had a significantly reduced risk of myocardial infarction compared to those who drank <1 cup/day.
Subjects who drank 1–3 cups/day had reduced risk of stroke compared to those who drank <1 cup/day.
LDL cholesterol is called the “bad“ cholesterol and is a risk factor for CVD. Subjects who drank ≥10 cups/day had lower LDL cholesterol levels compared to those who drank <3 cups/day.
The study was published in the International Journal of Cardiology.
Polyphenols found in green tea account for its beneficial effects. Epigallocatechin-3-gallate (EGCG) is the most bioactive compound of green tea, but other important ones include epicatechin, epicatechin gallate, and epigallocatechin.
Green tea has antioxidative activity and anti-inflammatory effects and can help the stability of the vascular endothelium. It can increase nitric oxide production, which helps blood vessel dilate and keeps them healthy. Green tea prevents vascular endothelial abnormalities and attenuates the development of arteriosclerosis.
Lipids and oxidized low-density lipoprotein cholesterol play important roles in atherosclerosis. Lowering LDL cholesterol is one way to lower your risk of heart disease. This study showed that green tea can lower LDL levels. Other research has shown that 500mg of catechin/day, equivalent to 6 or 7 cups of green tea, significantly decreased plasma oxidized LDL cholesterol after 4 weeks. . Other experiments showed that green tea can lower cholesterol and triglyceride concentrations in rats with hyperlipidemia.
Even more impressive is another study that showed that 580mg of green tea catechins (GTC) caused significant improvement in endothelial function in smokers by two hours after the first dose, and continued for the duration of the 2 week study.
So green tea can help lower your risk of CVD by several ways. Epigallocatechin-3-gallate in green tea has a favorable effect on vascular function, and can lower LDL and oxidized LDL cholesterol.
You can achieve beneficial effects with about 3 cups or more of green per day. For best effects, use organic tea leafs. Milk can interfere with absorption of the beneficial polyphenols, so drink milk at a different time that you drink green tea. Vitamin C can help increase absorption of green tea compounds, so enjoy it with fruits such as kiwis.
If you can, aim for 5-6 cups of green tea per day. This will greatly help you prevent heart disease.