Types of Catechin
Catechin is a type of flavanol within the flavonoid group of polyphenols. The main catechins found in green tea include epicatechin (EC), epigallocatechin (EGC), epicatechin gallate (ECG), and epigallocatechin gallate (EGCG). In green tea extract, the primary catechin is EGCG, making up about 59.1%, followed by EGC at 19.2%, ECG at 13.7%, and EC at 6.4%.
Health Benefits of Catechin
- Antioxidant Activity: Catechins neutralize harmful reactive oxygen species (ROS), preventing cellular oxidation, aging, and disease.
- Antiviral Activity: Catechins inhibit viruses, such as influenza, from attaching to cells, thereby preventing their proliferation and aiding in the prevention of colds.
- Anticancer Activity: Catechins remove ROS, inhibit mutations in cancer cells, and suppress cancer cell proliferation, aiding in cancer prevention.
- Cholesterol Reduction: Catechins reduce the absorption of dietary cholesterol and promote its excretion, specifically lowering LDL (bad) cholesterol while not affecting HDL (good) cholesterol, thus preventing arteriosclerosis.
- Blood Sugar Regulation: Catechins inhibit sugar absorption in the intestines, helping to moderate post-meal blood sugar spikes.
- Antibacterial Activity: Catechins combat foodborne pathogens like E. coli O157 and Helicobacter pylori, reducing the risk of food poisoning and gastric ulcers.
- Prevention of Tooth Decay and Bad Breath: Catechins inhibit the growth of Streptococcus mutans, bacteria that cause cavities, thus preventing tooth decay.
- Obesity Prevention: Regular catechin intake enhances lipid metabolism in the liver and increases energy expenditure, reducing body fat. Catechins also boost diet-induced thermogenesis, helping to prevent obesity.
Foods Rich in Catechin
- Epicatechin-rich foods: Apples, blackberries, broad beans, cherries, grapes, pears, raspberries, and chocolate.
- Catechin-rich foods: Soybeans, matcha, azuki beans, and cocoa.
Recommended Intake of Catechin
There is no established dietary intake guideline for catechin in Japan. However, regular daily consumption is recommended for health and disease prevention. The effective concentration for green tea catechins is at least 540 mg per day, equivalent to about 10 cups of green tea. Due to the bitterness of catechins, consuming such an amount directly from tea leaves can be challenging.