For centuries, people have harnessed the healing powers of the camellia sinensis plant to make green tea. Green tea is available as a traditional beverage, or as extract in a capsule. Unlike black or oolong tea, which also come from the camellia sinensis, green tea is not fermented. Steeping the tea leaves raw preserves the antioxidants inside, known as polyphenols. The efficacy of green tea varies by condition. Although a cold doesn't always include a fever, and vice versa, a fever is often caused by a virus. The properties of green tea may soothe both afflictions. Always check with your doctor before taking any supplement or herb, such as green tea.
Green tea leaves contain six types of antioxidants known as catechins. The stem, leaf veins and buds of the camellia sinensis plant each contain a different type of catechin. Green tea is rich in antioxidants because it contains the leaf, stem and bud of the plant. This diverse concentration of antioxidants in one beverage or capsule makes green tea an effective antiviral agent.
Viruses spread by infecting healthy cells in your body. As the virus strengthens, your body tries to burn off the infection by developing a fever. Green tea antioxidants reduce the infection rate of healthy cells, which reduces cold-like symptoms and fever. A 2005 study in "Antiviral Research" found that each of the six antioxidants in green tea helped block a different phase of infection among healthy cells, thus weakening the virus.
Dosing and Efficacy
Ingesting green tea in capsules or some other form twice daily may reduce the severity of your cold. A 2007 study in the "Journal of American College of Nutrition," found that consuming two capsules of green tea extract each day for three months reduced the duration of the cold and flu virus by two days compared to those who didn't take green tea. The virus-weakening antioxidants allow your immune system to combat illness and restore your health.
Because of its potency, taking green tea is not appropriate with certain medications, such as anti-clotting agents and birth control pills. Green tea is naturally caffeinated, with 8 ounces containing between 25 and 40 milligrams of caffeine. Do not take green tea if the medication you're on interacts with caffeine. Consult your doctor or pharmacist for information on medication interactions.