Green vs Black Tea: Caffeine, Flavor and Health Benefits

Green vs Black Tea: Caffeine, Flavor and Health Benefits

Green vs Black Tea: Caffeine, Flavor and Health Benefits

Green and black tea are two of the most popular caffeinated beverages around the world, and easily two of the most popular tea types. But how do they differ beyond color and flavor? This week we are comparing black tea with green tea, to see how they are processed, which tea has the most caffeine, and what benefits each tea type offers.

Don't forget, we have high caffeine tea blends for both green tea and black tea fans. So regardless of which you prefer, you can enjoy a Zesty cup or can of high energy tea.

 HIGH CAFFEINE TEAS  We get it - you can't function before caffeine hits your bloodstream. Good thing Zest has more caffeine than coffee, plus your stomach won't hate you for drinking it.   ENERGY: 3X the amount of caffeine found in regular teas FOCUS: L-Theanine for all-day, steady alertness HEALTH: No surgar and made with completely natural ingredients  SEE PRODUCT PAGE

Black Tea vs Green Tea

Black tea and green tea have many similarities, beginning with how they are grown and processed into dry tea leaves ready for consumption.


Origins and Production

Both green tea leaves and black tea leaves are harvested from the Camellia sinensis plant. There are many varieties of the tea plant and different cultivars. Different cultivars are used to produce different types of tea, although technically you could create every type of tea from leaves harvested from one cultivar.

The tea plant originates in China, where the Chinese have been growing and producing tea for centuries. The main difference between loose leaf tea types comes down to this production method.

Green tea is made from the first leaves and buds of the tea plant. They are quickly fired after they are plucked to prevent oxidation. This fixes the enzymes, ensuring the leaves retain their fresh and grassy flavors. They are then dried and processed into teabags or left as loose leaf.

Black tea is made in a similar way, but with an additional oxidation process. Once the leaves are picked, they are withered and allowed to oxidize. By exposing the leaves to oxygen, they start to turn brown. This alters the flavor, antioxidants, and health benefits of the tea. Once oxidized, they are dried and processed.



Green tea and black tea provide very different drinking experiences. The process of creating black tea turns the fresh grassy flavors into darker, malty flavors.

The differences are vast.

Green tea is typically light flavored, green or yellow in color, and has fresh notes of grass or hay. It can be sweet or astringent (or both). Using boiling water to make green tea can increase the bitterness, so let your water cool for a few minutes (to roughly 80C) before pouring it over the tea.

Black tea has a more rounded flavor profile. Instead of being grassy, it is rich and malty. Black tea has strong tannin notes, depth, and more body. If your usual poison is a cup of coffee, black tea will be more appealing than green tea. Check out our Spicy Masala Chai for a rich and high-caffeine black tea experience.

 holding cup of milky black tea


Each type of tea contains a different amount of caffeine on average. The exact milligrams of caffeine per cup are quite tricky to calculate. The tea plant cultivar, plus how it was grown, determines how much caffeine is in each leaf. Then how you brew your tea determines how much of that caffeine infuses into the water. The oxidation process does not impact the caffeine content of green and black tea.

Typically, tea contains less caffeine than coffee with one exception. At Zest Tea, we bump the caffeine content by adding additional plant-powered tea extract. Learn more about how much caffeine is in a cup of Zest Tea below.

Black teas contain approximately 47mg of caffeine per 8oz cup. This is a medium amount of caffeine in comparison to coffee. Black tea contains more caffeine than green tea and is a popular morning tea alternative to coffee, thanks to its bold flavor.

Green teas contain approximately 28mg of caffeine per 8oz cup. There are exceptions to this rule however. Shade-grown tea plants store more caffeine in their leaves, and don't forget matcha is a whole other ball game with up to 70mg of caffeine per serving. Learn more about green tea energy in our article The Zest Tea Guide to Green Tea Energy.

We firmly believe that drinking tea is better than coffee when it comes to energy, even though most tea blends contain less caffeine on average. This is thanks to an important amino acid that is only found in the tea plant - L-Theanine.



Tea comes in numerous varieties, types and packages. But whether you like loose leaf or teabags, green tea or black tea, you'll also be enjoying one of the unique amino acids produced by the Camellia sinensis plant.

L-Theanine interacts with the energy-boosting process of caffeine, by slowing the onset and prolonging smooth and steady productivity throughout your day. We've written a guide to how L-Theanine and caffeine interact - read Caffeine in Tea vs Coffee to learn more.

With the highest volumes of catechins and antioxidants (more on these below) you may think that a cup of green tea would contain the most L-Theanine. But that's not strictly true. Some studies have found that black tea could contain more L-Theanine - approximately 20mg. Just like caffeine, it varies from plant to plant and cup to cup.

Both black and green tea provide health benefits thanks to L-Theanine. If you want to track exactly how much L-Theanine you are consuming, our ready-to-drink energy teas are great. Blackberry Lime, for example, contains 100mg of L-Theanine per can.

 loose leaf black tea


Both black and green tea are a source of antioxidants. These nutrients found in numerous plants prevent or combat oxidants and free radicals. In layman terms, antioxidants prevent damage to the cells in your body.

Drinking tea is a great way to absorb antioxidant nutrients. But the types of antioxidants in each tea type vary.

Green tea is a source of EGCG (epigallocatechin gallate) which is an antioxidant linked to many health benefits such as reduced cardiovascular disease risks and cancer. There's even been a suggestion that EGCG could be used to treat coronavirus, including COVID-19.

Black tea contains theaflavins, thearubigins and some catechins, however the oxidation process does alter them. That's why the health benefits of black tea vary slightly to the benefits of green tea. Black tea can prevent free radicals from forming and "scavenge" for free radicals that may already be harming your body.


Green and Black Tea Health Benefits

When it comes to green tea vs black tea for health benefits, both have some interesting compounds with unique properties. If you want to stay healthy, we recommend drinking a regular cup of green tea and a regular cup of black tea, along with a balanced diet and plenty of exercise.


Weight Loss

Both green and black tea can be used for weight loss if you switch from a high-calorie drink to a zero calorie tea blend. Just make sure you pick a high caffeine tea like Zest Tea to keep your energy levels up.

Furthermore, the combination of EGCG and caffeine in green teas can significantly assist with weight loss and weight management. Teas that have undergone oxidation or fermentation, like black teas, can also assist weight loss through polyphenol-induced weight-loss mechanisms.

woman doing yoga by a river

Blood Pressure

Black and green tea can reduce your blood pressure when consumed on a regular basis. Tea made with green tea leaves has shown to be more effective than black teas for reducing blood pressure, however.

High caffeine beverages can increase your heart rate (although these effects are not long lasting) and provide a lot of energy, but a low caffeine green tea can have the opposite effect. L-Theanine in particular promotes calmness by reducing stress and anxiety.


Heart Disease

Green tea may prevent heart disease by dissolving calcium oxalate and neutralizing acids that are linked to cardiovascular disease.

Furthermore, drinking 3 or more cups of black tea per day is linked to a lower risk of coronary heart disease. The study does warn that limiting your daily intake to 8 cups is important to minimize any risk relating to excess caffeine consumption too.



Green and black tea may have a protective effect against several types of cancer, including oral cancer, according to an umbrella review. There's also suggestive evidence that tea could be used to prevent biliary tract, breast, endometrial, and liver too.


Zest Black and Green Energy Tea

The black tea vs green tea debate is easily settled - try both! At Zest Tea, we have both green tea blends and black tea blends. We pair our teas with organic, non-GMO ingredients for a little extra flavor, then bump up the caffeine with natural tea extract.

Not to brag, but this is a game changer when it comes to caffeine:

  • Zest green tea - 135mg per cup.
  • Zest black tea - 150mg per cup.

While our black tea still narrowly beats our green tea, both are higher than the caffeine content of a cup of coffee.

Check out our hot teas and cold ready-to-drink teas, both available in green tea and black tea blends.

 zest sparkling energy teas


Which tea is highest in caffeine?

Zest black tea is highest in caffeine, with 150mg per cup. For standard green and black tea, black tea still has the higher caffeine content at 47mg per 8oz cup.

Which is healthier, green tea or black tea?

Green tea is usually thought of as healthiest, but both have a great range of health benefits. Drink your tea without added sugar and milk, especially if you're aiming to drink tea for weight loss.

Why does black tea have more caffeine than green tea?

The tea plant cultivars used to create black tea typically have more caffeine in their leaves, thus creating strong tea. However, this is only an average. There are some green teas made from shade grown tea plants or the buds of tea plants which contain far more caffeine than a standard black tea.

Is black tea high in caffeine?

Compared to other tea types, black tea is moderately high in caffeine. Compared to energy teas and coffee, black tea is quite low in caffeine. Read our article Which Type of Tea Has the Most Caffeine? to learn more.

loose leaf green tea

Is green tea high in caffeine?

Green tea is typically low in caffeine, unless you're drinking Zest green tea which actually contains more caffeine per cup than coffee!

Which is better for weight loss, green tea or black tea?

Numerous studies have linked green tea to weight loss, but black tea may be beneficial too. Read our article about Searching for the Best Tea for Energy and Weight Loss to learn more.

What happens if you drink black tea every day?

It depends how much you drink. Long-term consumption of black tea is linked to numerous health benefits, including reduced risk of coronary heart disease. Most recommend drinking 3-8 cups per day. The FDA recommends consuming no more than 400mg of caffeine per day, which is equivalent to 8 cups of standard black tea or 2 and a half cups of Zest black tea.

What happens if you drink green tea every day?

Again, it depends on how much green tea you like to drink. Drinking a single cup per day will provide less than 30mg of caffeine. Unless you're very sensitive to caffeine, you're unlikely to feel any energizing effects (or health benefits).

PLANT POWERED ENERGY DRINKS  We get it - you can't function before caffeine hits your bloodstream. Good thing Zest has more caffeine than coffee, plus your stomach won't hate you for drinking it.   ENERGY: 150 mg caffeine - more than coffee FOCUS: L-Theanine for all-day, steady alertness HEALTH: Low to no surgar, and made with completely natural ingredients  SEE PRODUCT PAGE

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