Polyphenols reducing the risk of cancer
All cells in living organisms contain genetic material or DNA (deoxyribonucleic acid), which controls all activities, growth, and reproduction of cells.
In the initiation stage of cancer, DNA is damaged or undergoes a change (mutation), which alters the functions of the cells it controls and may initiate their transformation into cancer cells.
However, in most cases, the altered cells merely die.
In some instances DNA damage causes the rapid growth and multiplication of cells, a process called cancer initiation. Further changes facilitate the initiated cell to become a cancerous tissue. These constitute the promotional and progressive stages of carcinogenesis.
Agents that cause mutations (damage DNA) are called mutagens, and those that cause cancers are called carcinogens. Although all mutations do not progress to cancer, any agent that can damage DNA is a potential carcinogen. Certain chemicals, radiation, smoke, and viruses act as carcinogens. Radiation, such as beta-rays produced in nuclear reactors, causes mutations.
Ultraviolet (UV) radiation is a major cause of skin cancer. Smoking has been for a long time a well-established cause of human carcinogenesis.
Scientific investigations have shown that tea polyphenols could directly react and neutralize chemical carcinogens, reducing the risk of cancer.
Our body itself has enzyme systems (mainly in the liver) that act to detoxify toxic and carcinogenic agents which enter the body. Research has found that tea increases the activity of these detoxifying enzymes.
Chemical carcinogens and radiation also could produce free radicals and reactive oxygen species, which could damage the DNA, leading to carcinogenesis.
Therefore, antioxidants in tea could act to reduce the risk of cancer.
Furthermore, population studies have shown the anti-cancer properties of tea.