Catechins are antioxidant flavonoids from tea (especially green tea), cocoa, and some fruits. They help the body handle oxidative stress.
People take them to support heart health and maintain blood sugar levels already within a normal range. These compounds also promote immune function and healthy skin aging.
A typical dose is a catechin extract, such as green tea extract, taken with a meal to improve absorption. Caffeine content varies by source, so check the label. High doses can cause digestive upset or liver stress in sensitive people. Catechins may interact with blood-thinning medications.