How Much Caffeine in Coffee and Tea?
By Perry Luckett, CoffeeMan1
Because we’re in a coffee- and tea-related business, customers occasionally ask us questions about these two delightful beverages. One that comes up often is How much caffeine is in coffee or black tea? Another: Does green tea have caffeine?
Caffeine in green tea
According to the Mayo Clinic’s website, an average 8 oz. (237 ml) serving of green tea contains 25-29 mg of caffeine. But the longer you leave tea leaves in water just off the boil, the higher your caffeine amount. A cup of tea steeped for five minutes has nearly double the caffeine of a cup steeped for two.* If you steep green tea for 2-3 minutes, as most tea companies recommend, you can reduce your caffeine intake a lot from drinking coffee or a little from drinking black teas such as Darjeeling, Assam, or Ceylon.
Caffeine in coffee and black tea
As with many “how much” questions, the answers depend on several conditions: origin of the bean, processing method, and preparation method, including brewing time. For example, a cup of drip coffee contains about 115 mg of caffeine, but percolated coffee averages 80 mg per 8-ounce cup. A single shot of espresso contains only 47 to 64 mg of caffeine.
Still, we can use information from the Mayo Clinic and other sources as a rough guide:*
Why do we care about caffeine in coffee and tea?
Perhaps questions about how much caffeine is in coffee and tea or does green tea have caffeine stem from recent emphasis on caffeine as a boost to health—if we don’t overdo. It offers many health benefits, such as
- improving mental function
- enhancing physical endurance
- reducing the likelihood of cardiovascular problems
- possibly reducing the likelihood of melanoma skin cancers
But too much caffeine (more than 400 mg per day) can cause several negative conditions: irritability, anxiety, restlessness, acid reflux, increased heart rate, dehydration, high blood pressure, insomnia, and others.**
How you react to caffeine may depend partly on how much caffeine you're used to drinking. People who don't regularly drink caffeine tend to be more sensitive to its negative effects. Other factors may include genetics, body mass, age, medication use, and health conditions, such as anxiety disorders.
We here at Koffee Kompanions are happy to assemble these answers for you. And we offer our Thinsulate-insulated (by 3M) drink sleeves, cup covers, tea cozies, and French press covers to keep your caffeinated or decaffeinated beverages hot and flavorful every day.
* Sources for amount of caffeine in drinks
** Sources for negative effects of too much caffeine