Green tea is one of the healthiest beverages, but in certain conditions it may also cause adverse effects. Green tea’s compounds may interact with medications, supplements, or even other herbs. These are the possible interactions:
- Combining green tea with amphetamines, cocaine or ephedrine can be dangerous because these stimulants act in concert with caffeine to accelerate heart rate and increase blood pressure.
- Green tea contains vitamin K that can make warfarin, a blood thinning medication, ineffective.
- You can’t also mix green tea with aspirin because they both prevent blood from clotting. Using the two together may increase your risk of bleeding.
- Similarly, patients may be advised to stop drinking tea before undergoing surgery.
- Caffeine from green tea may also interact with phenylpropanolamine, used in many over-the-counter and prescription cough and cold medications and weight loss products, causing mania and a severe increase in blood pressure.
- In interactions with herbs and supplements, green tea may decrease the absorption of iron and folic acid supplements. Taking bitter orange with green tea can also increase your heart rate and blood pressure.
For these reasons, consult your doctor before drinking green tea.
Health problems can also arise due to excessive consumption of green tea. Drinking large amounts of caffeine, including from green tea, for long periods of time can lead to irritability, insomnia, heart palpitations, and dizziness. Nausea, vomiting, and loss of appetite are also linked to caffeine overdose. If you start to vomit or have abdominal spasms after drinking a lot of tea, it can be a sign of caffeine poisoning.
Who should not drink green tea
Pregnant and breastfeeding women, children under the age of 2 and people with kidney disorders, heart conditions, stomach ulcers and psychological problems are suggested to avoid taking green tea. People with glaucoma, anemia, liver disease, osteoporosis and diabetes should also avoid it. However, it is better to consult your doctor to get precise information about your health condition and the risk you may face if you consume green tea.