Whether hot, iced, or with honey, brewed green tea is chock full of health benefits. (One exception: Avoid bottled green tea, which is often filled with added sugar.) Made from leaves of the Camellia sinensis plant, green tea has a high concentration of powerful antioxidants called polyphenols and tea flavonoids known as catechins. These antioxidants help combat free radicals — substances that can alter and even kill cells in your body, causing premature aging, cancer, and other diseases — by neutralizing them. And fighting free radicals with green tea can have all kinds of benefits: Here are 10 scientifically supported reasons to add green tea to your diet.