Green Tea May Lower the Risk of Hematologic Malignancies.
Hematological malignancies are the types of cancer that affect blood, bone marrow, and lymph nodes. As the three are intimately connected through the immune system, a disease affecting one of the three will often affect the others as well. For an example, although lymphoma is technically a disease of the lymph nodes, it often spreads to the bone marrow, affecting the blood and occasionally producing a paraprotein (abnormal plasma protein).
Green tea is an evergreen shrub that has long been used in much of the world as a popular beverage and a respected medicinal agent. An early Chinese Materia Medica lists green tea as an agent to promote digestion, improve mental faculties, decrease flatulence and regulate body temperature. The earliest known record of consumption is around 2700 B.C. 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.
Many studies have reported that green tea appears to have anti-cancer benefits, but a new study has further confirmed these findings. The study included 41,761 adults who participated in the Ohsaki National Health Insurance Cohort Study in Japan. The participants completed a food frequency questionnaire at the start of the study, which allowed the researchers to quantify green tea consumption. The participants were then followed for nine years. It was found that 157 hematologic malignancies, including 119 cases of lymphoid neoplasms and 36 cases of myeloid neoplasms were documented in the study participants. The researchers discovered that compared to people who drank only one cup per day, five cups of green tea a day were associated with a 42 percent reduction in hematologic malignancies, and a 48 percent risk reduction in lymphoid neoplasms. These reductions in cancer risk were not affected by the gender or the body mass index of the participants.1
1 Naganuma T, Kuriyama S, Kakizaki M, et al. Green Tea Consumption and Hematologic Malignancies in Japan: The Ohsaki Study. Am J Epidemiol. Jul2009.