Green tea is known for its health benefits and its antioxidant content, which may reduce inflammation and lower the risk of several chronic diseases. However, consuming it in large quantities can cause side effects that warrant attention, according to a report by the medical website Verywell Health.
Digestive Issues
While drinking green tea is generally safe for most people, green tea extract supplements may cause nausea, constipation, or stomach upset.
High Blood Pressure
Because green tea contains caffeine, excessive consumption (more than 400 mg of caffeine daily) can cause high blood pressure, rapid heartbeat, headaches, anxiety, and difficulty sleeping. Decaffeinated green tea can be chosen to minimize these effects.
Sleep Problems
Caffeine can affect sleep quality; therefore, it is best to avoid drinking green tea at night. Excessive caffeine intake during the day can also increase anxiety and negatively impact sleep quality.
Green tea contains catechins, which may reduce the body's ability to absorb iron (Pexbay).
Green tea contains catechins, which may reduce the body's ability to absorb iron (Pexbay).
Iron Absorption
Green tea contains catechins, which may reduce the body's ability to absorb iron, increasing the risk of anemia in those who already have low iron levels. It is recommended to drink it between meals.
Liver Injury
Green tea rarely causes liver damage, and this is more likely to occur when green tea extract supplements are taken by people with a genetic predisposition or a history of liver disease.
Drug Interactions
Green tea may interact with some medications, reducing their effectiveness, especially when consumed in large quantities. These medications include beta-blockers, blood thinners, cholesterol medications, antidepressants, and osteoporosis treatments.
How Much Should You Drink Daily?
Most adults can safely drink green tea daily, provided they do not exceed 400 mg of caffeine per day. One cup contains 22 to 40 mg of caffeine. However, caution should be exercised if you are taking medications for heart conditions, blood pressure, liver problems, anxiety, depression, or osteoporosis, as caffeine may interact with these medications.