Green tea is an antioxidant and is used in promoting cardiovascular health and reducing serum cholesterol levels in laboratory animals and humans. Studies suggest that green tea contains dietary factors that help decrease the development of some infectious diseases and dental caries. Green tea has diuretic, stimulant, astringent, antibacterial, antifungal, anticarcinogenic, thermogenic and anti-inflammatory properties. Green tea has also been reported to enhance immunity.
Cardiovascular disease or heart disease is a class of diseases that involve the heart or blood vessels (arteries and veins). There are several risk factors for cardiovascular disease that are essentially immutable. These are older age, male gender, and a family history of CVD. Additionally, three major risk factors identified include cigarette smoking, dyslipidemia (high cholesterol), and hypertension. Other identified factors associated with increased risk for cardiovascular disease include physical inactivity, sleep problems, diabetes mellitus, rheumatoid arthritis, obesity, excessive intake of alcohol, thrombotic and fibrinolytic factors, elevated homocysteine levels, certain infections and inflammation, exogenously administered estrogens and androgens, certain psychosocial factors, increased fasting glucose. and frequency of migraines. The synergism of the presence of multiple risk factors must also be considered.
A study published in the journal, Nutrition, sought to assess the effects of green tea on metabolic syndrome and inflammation in obese adults. The eight week, randomized, controlled study included 35 participants with an average age of 42.5 years and an average BMI of 36.1. The subjects were randomly assigned to receive either four cups of green tea per day, 2 capsules of green tea extract and four cups of water per day or no treatment, which consisted of four cups of water per day and no green tea. Researchers collected fasting blood samples at screening, at four weeks and at the end of the eight week trial. It was found that green tea did not alter any biomarkers of metabolic syndrome or inflammation. However, it was determined that both green tea interventions reduced levels of amyloid alpha levels, which are thought to be a risk factor for cardiovascular disease. The green tea drink reduced amyloid alpha levels by 14.5 percent, while the extract reduced levels by 24.6 percent after eight weeks. These results suggest that although green tea may not have any effect on the features of metabolic syndrome, it does appear that it may reduce the risk of cardiovascular disease.1
1 Basu A, Du M, Sanchez K, et al. Green tea minimally affects biomarkers of inflammation in obese subjects with metabolic syndrome. Nutrition. 2010.