High Caffeine Tea - Everything You Need to Know

High Caffeine Tea - Everything You Need to Know

March 15, 2021

High Caffeine Tea - Everything You Need to Know

How many cups of tea do you need to drink to get that caffeine energy you need? It’s more than coffee, right? Traditionally, the answer is yes, that compared to coffee, a cup of tea contains less caffeine. This was true before high caffeine teas existed.


Tea with higher than normal caffeine contents can match (and even exceed) the levels of caffeine in your normal coffee wake-up call.


Everything you need to know about high caffeine tea, including what it contains, how it can help energize your day, and how it compares to other caffeinated beverages, is right here in our guide.


What is High Caffeine Tea?

High caffeine teas refer to a type of tea that has more caffeine than it normally would. By boosting the levels of caffeine in tea, you can get the same (or greater) energy buzz you usually would from a strong cup of coffee.

But of course, tea isn’t the same as coffee, so the energy boost is different too. Tea, which is made from the Camellia sinensis plant, naturally contains both caffeine and a variety of amino acids. One important amino acid is L-Theanine, which is not present in coffee.


That’s why high caffeine teas are so popular. They provide the energy boost you’re looking for, but with additional ingredients like L-Theanine for focus and even potential health benefits.


“High caffeine tea provides the same energy boost as other drinks with high caffeine content, but with higher amounts of focus and calm.”



High Caffeine Tea

L-Theanine and Caffeine - The Science Behind How High Caffeine Teas Work

Starting with the basics - caffeine is a stimulant. It reduces tiredness, giving you energy and alertness, but it doesn’t last forever.


Caffeine from coffee, provides a quick boost of energy, then fades away… until you grab a refill. With tea, it’s slightly different due to the L-Theanine. Together, caffeine and L-Theanine have a synergistic effect. This unique amino acid slows down the onset of the effects of caffeine, so your energy is smoother and prolonged, rather than all at once. This also means the caffeine energy slowly tapers off at the end of the day.


Furthermore, L-Theanine can affect your mood by stimulating GABA, serotonin and dopamine when it crosses the blood-brain barrier. As a result, you get a sense of calm and focus. Combined with the energy of caffeine, this is a fantastic recipe for productivity.


And that is why high caffeine tea is brilliant. It provides the same energy boost as other drinks with high caffeine content, but with higher amounts of focus and calm.

Drinking tea at desk


Key Benefits of High Caffeine Teas

In general, all high energy teas have quite a few benefits over other caffeinated drinks.


  • Provides more energy in fewer cups compared to normal tea types,

  • The extra caffeine comes from a natural source (tea leaves),

  • L-Theanine amino acids provide calm and focus,

  • That means you can forget about jitters and shakes,

  • Your energy is sustained and prolonged, rather than hitting you all at once,

  • There’s a smoother ‘come down’ as the energy wears off.


Wait, is tea with high amounts of caffeine dangerous?

There are some side effects from consuming too much caffeine. Alertness and energy turn to jitters, anxiety, and sleep troubles. Caffeine can also elevate your blood pressure temporarily and is linked to chronic headaches. But, you need to drink a lot of caffeine to experience overly negative side effects. 


Recommendations by the FDA are to consume no more than 400 milligrams of caffeine per day. That’s roughly equivalent to 8 cups of black tea, 4 or 5 cups of coffee, or 2.5 cups of Zest energy tea, for example. Drinking energy tea in moderation is perfectly fine.


Caffeine Content in Tea (and More)

Caffeine from tea is great for energy and focus, and as we just discussed, drinking too much caffeine from any source (more than 400mg) is not a good idea. So, as a helpful guide we’ve outlined the different caffeine levels in different teas, coffees, and energy drinks.


Note: We’re comparing caffeine levels per cup (8 ounces) and looking at the average caffeine levels for each tea type. However, there is quite a bit of variation and variability. For example, two green teas from different varieties of the Camellia sinensis plant, made from different leaves (large vs buds), brewed in different ways, will have different levels of caffeine. The more tea leaf you brew, the hotter the water, and the longer you brew for, the more caffeine ends up in your cup too. So, take these figures with a pinch of salt.



Fruit/Herbal Teas (0mg per 8oz)

Herbal teas and fruit teas are caffeine-free, so they contain 0mg of caffeine. This includes infusions like chamomile or valerian and red rooibos, a caffeine-free alternative to coffee and tea. As these teas aren’t made from Camellia sinensis leaves, they don’t contain any L-Theanine either. But that’s not to say these tisanes don’t have their own health benefits.

Fruit Tea

Decaffeinated Tea (2mg per 8oz)

Despite the name, decaf tea does contain caffeine. This is usually around 2mg of caffeine per cup of decaf black tea, which is roughly the same as decaf coffee. Tea is decaffeinated using CO2 (the same gas that makes sparkling drinks bubble), ethyl acetate, or methylene chloride before it’s sold as loose leaf or packaged into tea bags.
Decaffeinated Tea

Standard Green Tea (28mg per 8oz)

Unlike a black tea, green teas aren’t oxidized. Once the leaves are picked, they are fired and dried to keep them green before they can oxidize. This results in different flavors, and levels of caffeine. A standard cup of green tea contains much less caffeine than black tea or coffee, at around 28mg of caffeine. But there is an exception: matcha, but more on that later. 
Green Tea

Oolong Tea (37mg per 8oz)

Oolong tea can have varying amounts of caffeine, as oolong teas are so varied. Typically, oolong teas have more caffeine than green tea but less than black tea. On average, a cup of brewed oolong contains 37mg of caffeine. While black teas are fully oxidized and green teas aren’t oxidized at all, oolong tea falls in the middle. So, you can have highly oxidized oolongs that are dark and rich, and barely oxidized oolongs that are green and bright
 Oolong Tea

White Teas (40mg per 8oz)

The caffeine content of white tea varies a lot. As green and white teas can be quite similar in flavor and appearance, you’d think that their caffeine levels would be similar, but that’s not true. White teas have higher caffeine levels. It ranges from 6mg to 75mg of caffeine, depending on the part of the tea plant that’s used. The buds tend to contain more caffeine than the leaves, for example. This puts the average cup of white tea at 40mg of caffeine. White Tea

Black Tea (47mg per 8oz)

Black teas are hugely popular. Black teas are made from Camellia sinensis leaves, just like all other types of tea. The difference is, these tea leaves are fully oxidized before they’re fired, dried and packaged. A standard cup of black tea contains around 47mg of caffeine.
Black Tea

Pu-erh (65mg per 8oz)

Pu-erh is a fermented type of tea. Traditionally, it’s only made in the Yunnan province of China and sold as a ‘cake’ or brick rather than loose leaf tea or tea bags. Depending on the strength and age of the pu-erh, the amount of caffeine can be anywhere from 30mg to 100mg of caffeine per cup. The average is roughly 65mg of caffeine.
Pu-erh Tea

Matcha Green Tea (70mg per 8oz)

This powdered type of Japanese green tea is whisked into water, rather than infused and then removed. 1 teaspoon of matcha powder (about 2g) is the standard ratio for an 8oz cup and contains 70mg of caffeine.
Matcha Tea

Yerba Mate (85mg per 8oz)

Yerba mate tea is made from the leaves and twigs of the Ilex paraguariensis plant, rather than the Camellia sinensis tea plant. It’s popular in South America and it contains quite a lot of caffeine. There’s approximately 85mg of caffeine per cup of tea.
Yerba Mate



Coffee (64-96mg per 8oz)

The amount of caffeine in a cup of coffee depends on your method of making it. A single shot of espresso will contain around 64mg of caffeine, while a standard cup of drip coffee will contain 96mg of caffeine.

Decaffeinated Coffee (2mg per 8oz)

Just like a cup of decaffeinated black tea, decaf coffee isn’t exactly caffeine-free. Whether you use decaf instant coffee, or brew fresh from decaffeinated coffee grinds, there’s only around 2mg of caffeine in your cup of coffee.
Decaffeinated Coffee

Other Caffeinated Drinks

Soda and Soft Drinks (22-30mg per 8oz)

These drinks are caffeinated, but they tend to be lower in caffeine compared to drinking tea. A 12oz can of Coca Cola contains 34mg of caffeine plus 39g of sugar. For a healthier option, switching to Diet Coke ditches the sugar but actually contains 46mg of caffeine.
Soda and Soft Drinks

Energy Drinks (80mg per 8oz)

If you’re looking for high caffeine content, it’s often the energy drink that you reach for. These drinks are specifically designed to provide energy, usually through caffeine and a lot of sugar. Unlike caffeinated teas, the amount of caffeine in an energy drink is fixed and while the amount of caffeine isn’t usually listed by the ingredients list, you can find a precise figure if you do a little research online. Monster Energy, for example, has 80mg per 8oz which puts an entire can at 160mg and a Mega Monster at 240mg of caffeine. The downside is, you’ve also just consumed a bucket-load of sugar and sweetener.
Energy Drinks


Zest Tea

Zest Teas (100-150mg per 8oz) 

At Zest Tea, we use natural caffeine to bump the caffeine levels in our tea up to 150 milligrams. We also use natural non-GMO ingredients and little to no sugar, so our energy teas are better for you than sugary energy drinks. Our sparkling energy tea contains 150mg of caffeine per 12oz can and our hot caffeinated energy tea contains between 135-150mg of caffeine.
Zest Hot Tea  

Comparing Caffeinated Beverages

Ok, that was a lot of information. Here’s a helpful visual to see how all these beverages and their caffeine contents compare to one another.

Caffeine Content per 8 Ounces


Why Energy Tea is The Best Option

You’ve already read through a plethora of reasons why energy tea is so great, but there’s more. Okay, so we are a little biased… but one of the things we love so much about creating high energy teas, is the variety of flavors available.


By naturally increasing the caffeine levels in any tea type, you can enjoy your favorite Earl Grey black tea or smooth green tea and get that energy boost you need. So, instead of drinking cup after cup of crappy office coffee, you can choose a tasty, healthy, high caffeine alternative to power through your day. 


You can find high energy tea in loose leaf format, or in more convenient tea bags. There are even sparkling, iced, and other ready-to-drink energy teas to explore.


Tea and Caffeine FAQs

Couldn’t find the answer you’re looking for? Or just don’t have enough energy to read our full guide? We’ve been there! These frequently asked questions should clear things up. You can always message us, leave a comment, or join our mailing list to learn more about highly caffeinated teas.


Why should I drink high caffeine teas?

Tea with high amounts of caffeine provides lots of energy, without you needing to drink cup after cup after cup. These teas also contain L-Theanine and other beneficial amino acids that aren’t present in coffee, to keep you calm and focused. You’ll also avoid the jitters and caffeine crash as the effects wear off.


How do I choose a high caffeine tea?

Decide between loose leaf tea, tea sachets or sparkling energy tea, then pick your favorite flavor. All Zest teas contain 135 to 150 milligrams of caffeine.


Why does high caffeine tea give you focus?

So you can do more with your day! It’s the L-Theanine amino acid in tea that helps you stay calm and focus your energy.


Does green tea have caffeine?

Yes, green teas contain caffeine as well as L-Theanine, to provide energy and focus. Just bear in mind, green tea caffeine levels are quite low.


How much caffeine in green tea?

An average brewed cup of green tea contains around 32 milligrams of caffeine. Matcha, a specific type of green tea, contains as much as 35 milligrams per half a teaspoon of powder.


What tea has more caffeine than coffee?

Most types of tea don’t contain as much caffeine per cup compared to coffee. The exception is highly caffeinated teas. Tea types that have the highest caffeine (but still less than coffee) include matcha and yerba mate.


Where does the caffeine from highly caffeinated teas come from?

Zest Tea uses a blending method that enhances the caffeine content using a natural tea extract. The result is tea with more of the same kind of caffeine as what was already in there.


How does caffeine from tea make you feel?

Caffeine in tea makes you feel alert, energized, and wide awake. Caffeine and L-Theanine together in tea makes you feel both energized and focused - a great combination for productivity.





FDA caffeine recommendation


Side effects/dangers of caffeine https://www.healthline.com/nutrition/caffeine-side-effects#TOC_TITLE_HDR_7

Caffeine headaches https://pubmed.ncbi.nlm.nih.gov/15596744/

Caffeine levels in different types of teas https://www.healthline.com/nutrition/caffeine-in-tea-vs-coffee#caffeine-concerns 


Oolong caffeine source https://www.caffeineinformer.com/caffeine-content/oolong-tea 

L-Theanine levels per tea type



Pu-erh caffeine content


Coca Cola caffeine content https://www.coca-colacompany.com/faqs/what-is-caffeine