In several Asian population studies research suggests that the health benefits of green tea are based on people that typically drink 3 cups per day. The United Kingdom Tea Council recommends drinking up to 6 cups a day. Green tea in large quantities can lead to some side effects like caffeine intolerance and minerals overdose.
Caffeine intolerance is the most common side effect to drinking too much green tea. Green tea contains half the amount of caffeine found in coffee, so moderate consumption is unlikely to cause problems to the majority of people. For those who are sensitive to caffeine, here are symptoms to watch out for: restlessness, irritability, sleeping problems, tremor, heart palpitations, loss of appetite, upset stomach, nausea, frequent urination and skin rash. Experts recommend 300 milligrams of caffeine a day as being safe for most individuals. According to the United Kingdom Tea Council, this is equivalent to 6 cups a day.
Minerals Overdose is another less common complaint when consuming too much green tea. The tea plant accumulates minerals such as aluminum, manganese and fluoride from soil and water. These minerals can be harmful when consumed in large amounts over many years.
The Chinese have been drinking tea, including green tea and organic chai tea, for more than 2,000 years. But until A.D. 600, green tea was used mainly as a medicinal tonic, not an everyday beverage. Like any other herbal medicine, green tea's healing power has to be carefully harnessed. There are times when we should avoid drinking too much green tea. Tea can cause indigestion to those with a sensitive stomach. It also reduces absorption of non-heme iron, causing problems to those prone to iron deficiency anemia. We can take precautions against these side effects by avoiding tea drinking around mealtimes or on empty stomach.