In our bodies are things known as free radicals. These come from our environment as well as habits like smoking. These free radicals have been known to cause many health problems up to and including cancer. Antioxidants like polyphenol help prevent the damage that is done by free radicals, and green tea is 30-40% polyphenol while black tea is only ten.
Cholesterol is the main culprit in heart disease; it comes from eating a diet high in fatty foods. A practice that is common among French people, however they have a much lower incidence of heart related diseases. One theory suggests it is because of their high consumption of green tea.
What we do know for certain is that people who drink green tea on a regular basis have a lower LDL cholesterol count, which is the bad cholesterol. One recent animal study has shown that the polyphenols inhibit the absorption of cholesterol in the intestines, leading to its removal from the body through elimination.
The other culprit in heart disease is smoking and yet despite the fact that 75% of Japanese are heavy smokers they too have a lower incidence of heart disease than we do. Again, this could be because green tea is an essential part of their overall diet. Again, animal studies are showing that the antioxidants may be responsible for killing the cancer cells.
When a person suffers from diabetes, the body is not creating enough insulin. Insulin is produced in the pancreas to regulate the sugar levels in the body. For the diabetic the pancreas produces little or no insulin or the cells do not respond. In one study, subjects were given 300 mg of green tea that is about three cups, ten minutes before they consumed 50 mg of starch. The result was that sugar and insulin levels did not rise as much as would normally be expected.
As more studies are done it is clear that the benefits of green tea are many. Heart disease, cancer, and diabetes are just a few of the possible health problems that green tea addresses. Lately it is even been claimed that benefits of green tea include weight loss.