There’s a lot of information floating around when it comes to caffeine levels in green tea compared to other drinks (like coffee). That's why we've tapped Monica Auslander Moreno—a registered dietitian and nutrition consultant for RSP Nutrition—to separate fact from fiction.
To start, it’s important to understand how caffeine affects the body. A naturally occurring compound found in somewhere around 60 varieties of plants (including coffee and tea), caffeine is a central nervous system stimulant that many people have come to rely on for energy. “[Caffeine] has been known to aid with attention and reactive time, as well as provide more energy, strength, and endurance for physical activities,” says Moreno. It’s also a gastric stimulant—which is why you may find yourself running to the bathroom after your morning cup of coffee—and a vasoconstrictor, which means it narrows the blood vessels and raises blood pressure.
“In susceptible individuals, [caffeine] may contribute to anxiety,” Moreno says, adding that the effects of caffeine may be beneficial and enjoyable for some people, and hard to tolerate for others. Maybe you’re someone who can’t fathom leaving your house in the morning before drinking coffee, or perhaps you’re someone who feels anxious after just a small amount of coffee. Either way, the point is—caffeine affects everyone differently. Some people can metabolize caffeine very quickly, which makes them more tolerant to it, whereas others are very sensitive. So is green tea a healthier source of caffeine than coffee? We investigate, below.
How Much Caffeine Is In Green Tea?
An eight-ounce cup of green tea usually contains somewhere between 20 and 50 mg of caffeine, which is a fairly low dose of caffeine according to Jeanette Kimszal, a registered dietitian nutritionist based in New Jersey.
Keep in mind that not all green tea is the same—it comes in many varieties, including matcha, sencha, and bancha. The specific amount of caffeine in green tea will depend on the type of tea and how it’s brewed.
“We've seen anywhere from seven mg per gram to 84 mg per gram of caffeine in various types of green teas,” says Miriam Colman, marketing specialist at Sugimoto Tea Company, which is a green tea company based in Shizuoka, Japan. Typically, matcha is the variety most likely to be high in caffeine, yet some matcha contains little caffeine.
“For non-matcha green teas, unless the green tea is roasted like hojicha, mixed with herbal ingredients, or cold brewed, it's best to assume that a cup of green tea will have a noticeable amount of caffeine,” Colman says.
How Does Green Tea Compare to Other Beverages?
The amount of caffeine in coffee varies depending on the type of coffee bean, how the beans are roasted, and how the coffee is brewed. Typically, an eight-ounce cup of coffee has somewhere between 70 and 140 mg of caffeine (far surpassing green tea's typical range of seven to 84 mg). But most people drink much more than eight-ounces of coffee. At Starbucks, for example, a tall drink is 12-ounces, a grande is 16-ounces, and a venti is 20-ounces. Either way, most coffee contains far more caffeine than green tea.
Green Tea: Seven to 84 mg of caffeine per eight ounce serving
Coffee: 70 to 140 mg of caffeine per eight ounce serving
Energy Drinks: 40 to 250 mg of caffeine per eight ounce serving
Other drinks contain substantial amounts of caffeine as well. For example, energy drinks usually have somewhere between 40 and 250 mg of caffeine for an eight-ounce serving, and soft drinks contain around 30 to 40 mg of caffeine in a 12-ounce serving. This caffeine chart from the Center for Science in the Public Interest may be helpful if you’re curious how much caffeine is in some of your favorite drinks.
How Much Caffeine Can You Safely Consume Each Day?
Rather than deferring to broad guidelines that apply to everyone, Moreno explains that the amount of caffeine you take in each day should really depend on your individual tolerance and metabolism. If you’re feeling anxious or having trouble sleeping after consuming coffee, it may be wise to cut back a bit, whereas others can consume higher amounts of caffeine without problems. If you do decide to cut back, be sure to do so gradually to avoid headaches and other withdrawal symptoms. It’s also a good idea to speak with a physician if you have any questions or concerns about caffeine intake.
Green tea may be a good alternative for people who are looking for a drink with a lower dose of caffeine per serving, Kimszal says. But as mentioned, caffeine tolerance varies from person to person, and caffeine content varies from beverage to beverage, so the ideal source of caffeine won’t be the same for every individual.
While caffeine definitely provides a boost of energy, it shouldn’t be the only thing you rely on it to keep you going throughout the day, nutritionists say. As you reach for caffeine throughout the day, remind yourself that food can be an equally good (or better) source of energy than caffeinated drinks.
Next, read how this teen cured her cystic acne with green tea and honey