Fitness
Fact-checked

At WiseGEEK, we're committed to delivering accurate, trustworthy information. Our expert-authored content is rigorously fact-checked and sourced from credible authorities. Discover how we uphold the highest standards in providing you with reliable knowledge.

Learn more...

What are the Most Common Green Tea Side Effects?

Jessica Ellis
Jessica Ellis
Jessica Ellis
Jessica Ellis

Green tea is a beverage considered by many to be supremely healthy, and diets, health plans, and weight loss regimens all include it as a beneficial component. Though non-toxic, green tea can have side effects when consumed in substantial quantities. To avoid any possible side effects, most health experts recommend drinking only one or two cups per day.

Most green tea side effects are related to the relatively high caffeine content in most tea beverages and supplements. Although the amount of caffeine is lower than in coffee or black tea, there is enough in green tea to cause anxiety, sleeplessness, a feeling of hyperactivity, rapid heart rate, and increased blood pressure. Children and people with medical conditions that are sensitive to caffeine are typically told to avoid the tea or drink it in limited quantities.

Green tea.
Green tea.

Certain medical conditions may make the side effects of green tea more likely and potentially harmful. Some experts recommend that patients discuss how much they drink with a healthcare professional if they have kidney problems, hyperthyroid disorder, anxiety issues, or blood disorders. Most of these complications are related to caffeine content, and they can sometimes be avoided by drinking decaffeinated varieties.

Green tea drinkers should brush their teeth at least twice daily to avoid staining.
Green tea drinkers should brush their teeth at least twice daily to avoid staining.

There is some evidence that it is possible to overdose on green tea, particularly if a large amount of concentrated supplements are consumed. Signs of an overdose may include a pounding heart, excess sweating, vomiting, and abdominal pain or spasms. People who experience these symptoms after drinking green tea or taking supplements should contact emergency medical help or poison control immediately.

A green tea overdose can cause abdominal pain.
A green tea overdose can cause abdominal pain.

Some green tea side effects are related to other properties of the tea. Green tea is typically a pale tan or green color, and it can stain the teeth if they are not properly cleaned. Drinkers should be sure to brush teeth at least twice a day to avoid staining, or brush after each glass of green tea to promptly remove stains.

Although rare, some people have an allergic reaction to green tea. Symptoms may include hives or a rash, swelling of the face or throat, and difficulty breathing. Anyone who experiences these symptoms should consult a medical professional immediately. He or she may also wish to consult with an allergy specialist to do further testing.

Five cups or more of green tea per day is considered too much.
Five cups or more of green tea per day is considered too much.

Typically, green tea can be a tasty drink loaded with antioxidants. Some advocates claim that the beverage is extremely beneficial to weight loss and makes a better caffeinated choice than coffee or energy drinks. To avoid the possible side effects, people should drink or take supplements in moderate doses and stop consuming it if they experience any side effects.

Jessica Ellis
Jessica Ellis

With a B.A. in theater from UCLA and a graduate degree in screenwriting from the American Film Institute, Jessica is passionate about drama and film. She has many other interests, and enjoys learning and writing about a wide range of topics in her role as a WiseGEEK writer.

Learn more...
Jessica Ellis
Jessica Ellis

With a B.A. in theater from UCLA and a graduate degree in screenwriting from the American Film Institute, Jessica is passionate about drama and film. She has many other interests, and enjoys learning and writing about a wide range of topics in her role as a WiseGEEK writer.

Learn more...

Discussion Comments

donasmrs

@fify-- Supplements and energy drinks are problematic because they don't usually only contain green tea. They have lots of other ingredients added to give people energy. And some poor quality supplements may even have ingredients that are harmful.

If you want to enjoy the benefits of green tea, have a single cup of freshly brewed green tea without sugar. Use either loose tea or tea bags from the grocery, try to get organic if possible.

The green tea powders used in commercial green tea products have added caffeine and other stimulants that affect various systems of the body like blood pressure and blood sugar.

fify

I experienced negative side effects from a green tea extract supplement I was taking. It gave me heart palpitations as well as a headache. I've not used any type of green tea product since.

burcinc

I don't think one to three cups of green tea per day is going to cause issues for most people. Green tea is one of the best teas to have because of it's low caffeine content and detoxification properties. It is known to help aid weight loss and help prevent cancer.

I can only imagine green tea being a problem if someone has a very low tolerance for caffeine. But most of us, who have at least one strong caffeinated drink like coffee or soda per day, will not react much to the caffeine levels in green tea.

The only side effect of green tea I've noticed is that if I drink it when I'm not very full, it does make me hungry after a couple of cups. So I have it after meals now and it's not a problem.

Post your comments
Login:
Forgot password?
Register:
    • Green tea.
      By: NataliTerr
      Green tea.
    • Green tea drinkers should brush their teeth at least twice daily to avoid staining.
      By: Ljupco Smokovski
      Green tea drinkers should brush their teeth at least twice daily to avoid staining.
    • A green tea overdose can cause abdominal pain.
      By: Africa Studio
      A green tea overdose can cause abdominal pain.
    • Five cups or more of green tea per day is considered too much.
      By: aleksandra_1981
      Five cups or more of green tea per day is considered too much.
    • An allergic reaction to green tea may include hives.
      By: Jürgen Fälchle
      An allergic reaction to green tea may include hives.