Health Nutrition & Diet How Much Caffeine Is in Green Tea? Here’s How It Compares to Other Drinks Drinking green tea has its benefits, but it has caffeine, too. By Lacey Muinos Updated on August 08, 2024 In This Article View All In This Article Overview Caffeine Content Green Tea vs. Other Beverages Health Benefits FAQs A good caffeinated beverage is a favorite of many folks—especially in the morning. While coffee holds the top spot for the nation’s preferred source of caffeine—with an estimated 67 percent of the U.S. drinking coffee daily—we can't forget about tea. Many people opt for a cup of warm tea, especially green tea, another caffeinated beverage with various health benefits. We asked registered dietitians to explain green tea's caffeine content, factors that affect how much caffeine is in each cup, and how green tea stacks up to other caffeinated drinks. Jenna Volpe, RDN, LD, CLT, is a registered dietitian in Austin, Texas. Maggie Moon, MS, RD, is a Los Angeles–based registered dietitian and bestselling author. What Is Green Tea? Green tea comes from the Camellia sinensis plant and contains caffeine. However, it retains its green color and many nutrients because it doesn't undergo the full oxidation process. Black tea is typically fermented (breaking down sugar), while green tea is not. Thus, green tea is lighter in color and flavor than black tea, and it usually contains less caffeine. Under the umbrella of tea, there’s an entire world of different varieties. You can find (typically non-caffeinated) herbal teas like peppermint, chamomile, and ginger tea. Other teas come from the Camellia sinensis plant, including black, white, and green tea, among others. Of them, green tea gets a lot of credit for being high in antioxidants and giving the brain a potential boost in cognition. What Is Caffeine? Caffeine is a natural stimulant that affects the central nervous system. It boosts alertness and reduces fatigue. You'll commonly find it in tea, as well as coffee, chocolate, and some soft drinks. Alexthq/Getty Images How Much Caffeine Does Green Tea Have? Because green tea is made from the leaves of the Camellia sinensis plant, and since this plant naturally contains caffeine, so does the resulting tea. Unless the tea has undergone a decaffeination process, all types of green tea contain some amount of caffeine, but the amount of caffeine varies by type. “The caffeine content in green tea may vary depending on the type of tea,” says registered dietitian Jenna Volpe. Varieties like matcha and sencha are examples of green teas with the highest caffeine content. Because the caffeine content in green tea exists on a spectrum, the U.S. FDA estimates an 8-ounce cup of green tea can contain anywhere from 30 to 50 mg of caffeine. There may be cases where it’s even higher due to the varying factors that can affect green tea's caffeine amount. If you're curious about the specific amount of caffeine in the green tea bags you have at home, most brands will include the caffeine amount on the packaging somewhere (on the box or canister, for instance). You can also usually find it by doing an internet search of the brand and its tea product for more information. Factors That Affect Caffeine Content The caffeine content in green tea can be impacted by a few factors, including the water temperature during steeping, how long the tea steeps, and the age of the tea leaves. In terms of storage and environment, “time, light, and heat generally seem to degrade potency in herbs, so younger green tea leaves are usually higher in caffeine,” Volpe notes. Using hotter water to make your green tea and allowing it to steep for longer can have a significant impact on extracting (aka increasing) caffeine and other compounds in green tea. Caffeine Content of Different Types of Green Teas Despite outside factors affecting caffeine content, some common varieties of green tea are known to have higher amounts of caffeine. Matcha green tea contains the most caffeine of all the types of green tea. “Matcha is a special type of green tea that involves grinding the tea leaves into a fine powder,” explains registered dietitian Maggie Moon. “Because drinking matcha means consuming the whole leaf powder, it is higher in caffeine than simply drinking an infusion of green tea leaves.” Researchers estimate that the caffeine in matcha falls between 18.9 and 44.4 mg per gram—nearly double that of regular green tea. A typical serving of matcha is about 2 grams, which yields up to 88.8 mg of caffeine per cup. Sencha green tea, another popular Japanese green tea, is also higher in caffeine than your typical bagged and steeped green tea. There isn’t as much research on the compounds found in sencha compared to other teas, but sencha tea is believed to contain up to 75 mg of caffeine per cup. How Much Caffeine Should You Have Per Day? According to the FDA, the safe upper limit of caffeine for most adults is around 400 mg per day. Some groups should limit their caffeine intake further, such as children and people who are pregnant or breastfeeding. “It’s important to be aware of all food and drink sources of caffeine, including the caffeine in green tea, because caffeine is a psychoactive stimulant that affects people differently,” Moon explains, adding that some people are more sensitive to caffeine than others. Caffeine in Green Tea vs. Other Beverages Caffeine is a stimulant and shouldn’t be consumed in excessive amounts. From your morning pot of coffee to your afternoon tea, and perhaps a soda with dinner or even a post-meal slab of chocolate, it’s easy to get doses of caffeine throughout the day. It can add up quickly, so here’s what you need to know about consuming caffeine in safe, healthy amounts and how the caffeine in green tea compares to other beverages: Soda: 30 to 40 mg per 12 ouncesGreen tea: 30 to 50 mg per 8 ouncesBlack tea: 30 to 50 mg per 8 ouncesCoffee: 80 to 100 mg per 8 ouncesEnergy drinks: 40 to 250 mg per 8 ounces “On average, an 8-ounce cup of standard brewed green tea provides about 8 to 10 percent of the FDA’s daily recommended upper limit of 400 mg,” Volpe says, adding that green tea tends to contain less caffeine than most popular caffeinated alternatives, though there are exceptions. And it’s usually gentler and has the added benefit of being free of added sugars, Moon adds. Top Health Benefits of Green Tea A couple of cups of green tea per day can certainly perk you up in a healthy way, but that’s not all it has to offer. It’s also a good source of beneficial compounds. Disease Prevention Green tea is a great source of antioxidants, which help fend off free radicals that can damage healthy cells and contribute to disease. “The majority of green tea’s health benefits are attributed to its antioxidants, especially a catechin called epigallocatechin gallate (EGCG),” Volpe explains. These catechins may even inhibit some types of cancer, such as breast cancer. Relaxation and Focus Green tea is also a source of an amino acid called L-theanine, which can influence mood and cognitive function and is commonly associated with reducing anxiety. “Research shows the combination of L-theanine and caffeine improves mental focus,” Moon says. Its anti-aging and cognitive benefits may even offer some protection against neurodegenerative diseases like Alzheimer’s, notes Volpe. Athletic Performance Of course, the caffeine itself proves beneficial in certain contexts and moderation. Caffeine is touted as giving athletes a boost in athletic performance, Moon says, pointing to a study linking caffeine to increased exercise performance. Frequently Asked Questions Do green tea bags have the same amount of caffeine as loose-leaf green tea? Green tea bags generally contain less caffeine than loose-leaf green tea. This is because tea bags tend to use smaller, more broken-up tea leaves, which may have a lower caffeine content than larger leaves. However, the exact caffeine content will vary by brand, the quality of the tea, and the method of brewing. How does drinking green tea affect you? Drinking green tea offers tons of health benefits due to its rich content of antioxidants. And, thanks to its moderate caffeine content and the calming amino acid L-theanine, it can give you a boost of energy without the jitters that often come with that. Therefore, you can drink green tea in the mornings for that extra immunity and energy boost to kickstart your day. Should you drink green tea at night? Drinking green tea at night is not recommended for everyone, especially if you are sensitive to caffeine. While the caffeine in green tea is lower than in coffee, it can still interfere with your sleep, making it more difficult to fall or stay asleep. However, some people find the L-theanine in green tea to be relaxing before bed. A decaffeinated green tea can give you the calming effects without disrupting your sleep quality. What Is the Best Tea Kettle? Was this page helpful? Thanks for your feedback! Tell us why! Other Submit Sources Real Simple is committed to using high-quality, reputable sources, including peer-reviewed studies, to support the facts in our articles. Read our editorial guidelines to learn more about how we fact check our content for accuracy. National Coffee Association. “Daily Coffee Consumption at 20-Year High, up Nearly 40%.” www.ncausa.org, April 11, 2024. 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