There is a huge mix up regarding the caffeine contents of white tea compared to other teas like black and green, with a shocking number of tea ‘experts’ claiming white tea is basically caffeine free. Spoiler alert: it’s not!!
- What “caffeine” actually is & how it makes tea good for calm focus
- How brewing determines your “caffeine in the cup” & why white tea’s caffeine content isn’t so simple
- Caffeine comparison: levels of different teas and popular drinks
- Caffeine in different types of white teas
- Why does the white tea caffeine myth continue?
So let’s sort this mess out!
It’s been a pervasive myth in the tea world for decades that white tea has lower caffeine than black or green tea, with even large tea companies claiming white tea was/is practically decaf (Rate Tea, 2018). And it is easy to understand why: when you look at a nice cup of white tea, or take a sip, it is lighter and less tannic than, say, a black tea, and feels calming (Mcbane, 2021).
Calming, though, is not the same as naturally decaf! At the end of this article we’ll look at why this thinking still continues. But first…
What is Caffeine? Why do tea plants have caffeine?
So what are we talking about here? Why is caffeine even a thing?
Caffeine, nitrogenous organic compound of the alkaloid group, substances that have marked physiological effects. Caffeine occurs in tea, coffee, guarana, maté, kola nuts, and cacao - Britannica, 2021
Other “alkaloids” include nicotine and morphine, so this is definitely a drug! (Britannica, 2020).
Caffeine in its pure form is a bitter white powder, It has a half-life of between 1.5 and 9.5 hours, where the body metabolises it and it loses its potency (IMCMNR, 2001). That bitterness is pretty essential as in plants, caffeine is an antioxidant produced to fend off pests, as they don’t like eating bitter leaves.
During the spring growing season (or flush), the tea plant produces caffeine and sends it to its tender young shoots in particular because these are the most vulnerable and most important. This means, leaves and buds so they don’t get eaten (Ye NaiXing, 2010).
Caffeine is the world’s most widely consumed legal psychoactive drug (New Scientist)
As the tea leaves grow and mature, their caffeine levels drop (as they don’t need the same level of protection any more). It then makes sense that the teas with the highest caffeine levels are those made from the bud and first two leaves of the tea bush, especially when harvested during the spring flush (Takeda, 1994).
L-theanine (not to be confused with theine!) is another type of antioxidant also produced by the tea plant and is also concentrated in the tea shoots and buds, and when you combine caffeine and L-theanine you get caffeine’s alertness and L-theanine’s calm relaxation. The caffeine alertness without the peak and trough of energy. Hence, white tea’s deserved reputation for being a calming tea – just definitely not a sleep tea. If anything it’s a focus tea like green tea for the same antioxidant reason/combination.
So we solved it right? White tea leaves have the most caffeine of the traditional Camellia sinensis teas (black, oolong, green, white, pu-erh). So why the confusion? ….BUT WAIT!!!! What matters more than what technically has more caffeine in the leaf, is what gives you more caffeine in the cup….
Caffeine in the Cup, How Brewing Affects Caffeine
White tea has the most caffeine of true teas. But traditionally it does not give the drinker as much of a caffeine hit as other teas in reality, and that is due to how it is drunk.
Leaf Size
Like any infusion of one substance into another, the more surface area of the two touch, and so the more easily one dissolves into the other (or parts are extracted). So in reality, the caffeine molecules in whole tea leaves are harder for water to extract compared to broken tea leaves.
So white tea might have more caffeine per gram of tea leaf, these are some teas where in an infusion they will give you a more caffeinated cup, in order of caffeine going from high to low:
- Ground coffee, tiny particles of coffee beans (even though coffee naturally has less caffeine that tea - coffee has around 1.1-2.2% and tea leaves are 3.5% caffeine) (Wartenberg, 2019)
- “Fannings” or “dust” tea where black tea is ground into a fine dust (unsurprisingly!). This is what most teabags are made from such as the classic Yellow Label Lipton tea bags
- “CTC” tea where black tea is “crush-tear-curl”-ed. It’s not as dusty as fannings up tea and so it takes longer to feel the energy boost
- “Broken leaf” tea is somewhere between CTC and whole leaf, not macerated like dust or CTC tea, but still not the finest whole leaves. E.g. “BOP” broken orange pekoe black tea, goes for cheaper.
The surface area effect is significant (and of course makes sense). For example, a tea bag full of green tea dust with a boiled kettle is going to give you much more caffeine in the cup than the same quantity of high quality silver needle white tea brewed at just 175F (80C) (despite white tea technically having more caffeine in their leaves).
You might have experienced the jolt from a cup of joe or strong black tea (that has been minced up), versus the sustained energy from whole leaf black, green, oolong or white tea (Wartenberg, 2018).
Water Temperature
Caffeine is water soluble, and dissolves out of the tea leaves and into your pot fairly easily. The hotter the water the greater (energy for) movement of the water and tea particles and so the more actively the caffeine “comes out” of the tea leaves into the liquor you drink.
Traditionally, black tea is made with boiling water, 212F or 100C. White tea often is made with lower temperatures anywhere from 140F (60C) to 203F (95C). So with the mechanism of infusion, more of the constituent parts of the tea, such as caffeine, will be extracted from the leaves in a faster time.
This is why black tea feels like it has the highest caffeine levels, because it is! Black tea, the drink that is, not the black tea leaves as we discussed. Most of the time black tea is made using 1) boiling water and 2) tea dust or fannings in a teabag, despite generally being made from older (less caffeinated) leaves. In other words, there’s a huge surface area and high brewing temperature for fantastic extraction of caffeine.
Malaysian tea fields, from our visit. Almost all destined for black tea
Other Methods of Consumption:
There are also other ways to brew, or drink tea. For example:
- Eating Tea: Matcha tea - mat-cha means ground-tea. A type of tea called tencha is shaded during growth, which stresses the tea bush, leading it to make more chlorophyll. High school biology will remind you this is what makes leaves green, and so this is why matcha is so green. When you brew matcha, you whisk the actual powder into water and so when you consume it, you are drinking. All this to say - when you eat the leaf itself, you are ingesting 100% of the caffeine, the L-theanine, and EGCG, one reason matcha was traditionally drunk by Buddhist monks to aid meditation.
- Pressure Infusion / Espresso: You know the buzz of the coffee machine? That’s the pump forcing hot water through the densely packed coffee grounds. Well you can also do that with other ground teas such as rooibos tea or “red espresso” as it is sometimes called. You can put it into a coffee machine! We said that temperature impacts the speed of infusion? Well pressure does as well. As it happens rooibos is naturally caffeine free, but you get the point, it’s another method of infusion that extracts more, hence why espresso is known for high caffeine.
The Never Ending Caffeine Journey
This is a wide subject, with many more variables we haven’t even covered but you should have in your mind:
- Brewing length, which we haven’t touched on here so far. Naturally the longer you brew the more infusion takes place, especially if the tea is being continuously heated like on a samovar
- If the bush was given nitrogen fertilizer, this boosts caffeine levels by 14% (Qiao, 2018)! (Or other enhancers and fertilizers)
- The age of leaf (bud vs leaf). We did say younger leaves have more caffeine, so this is a spectrum. For example, in the Indian system big, old, further down the tea bush, leaves such as pekoe or souchong leaves are used for or cheap black teas or covered up with flavoring, as the leaves are seen to be of lower quality (see our Tea vs Tisane Primer)
- How it was processed, such as pu-erh’s burial (fermenting and piling) which raises its caffeine level or hojicha’s roasting, which reduces its caffeine
- Special antioxidants: Because of tea’s combination of L-theanine and caffeine, this causes the body to slowly process them, resulting in a slow release of caffeine “energy”. This characteristic of white and green tea is what will keep you awake all night long – there’s a reason monks use green tea for meditation! In green tea for instance, EGCG, is what prevents the famous energy spike and crash from coffee (see our post on antioxidants in green tea to learn more)
- The strain of tea - Camellia sinensis assamica has more caffeine than Camellia sinensis sinensis for example (the former is used for most Indian and African tea, and the latter forming more of Chinese tea) (Takeda, 1994)
…and the list goes on. Here though we are dealing with white tea only as otherwise we could research and write a novel on it!
Caffeine levels per tea type are tricky: For example, there was even a study of caffeine in brewed tea in 2008 that found no consistent results, across all varieties of tea (Chin, 2008).
What are the caffeine levels in other common foods/drinks?
It’s now time for the numbers! To give you something to compare against, these are the caffeine levels of various teas and soft drinks (UoU, 2004). All of these are for one serving / mug / bottle, and of course should be taken as indicators, rather than guaranteed numbers, due to all the considerations listed above:
|
8oz Mug of Black Coffee |
95 mg |
|
8oz Yerba Mate |
90 mg |
|
12oz Red Bull |
80 mg |
|
12oz Mountain Dew |
55 mg |
|
8oz Green Tea |
35 mg |
|
1 oz Espresso |
64 mg |
|
12 oz Coca Cola |
34 mg |
|
8oz Matcha |
70 mg |
|
8oz Hojicha |
7 mg |
|
8oz Decaf tea |
2 mg |
|
Chocolate |
20 mg/oz |
|
Black Tea |
22-25 mg |
Different Caffeine Levels in Various White Tea Types
There have been several studies trying to determine caffeine levels of different teas, with varied results. To save you the time and effort of trying to figure out what they heck they all say, and the names of the different teas (Silver Needle alone has several names and spellings!), here is a summary of the main caffeine studies I found (Yang, 2001; Chen, 2007; Czernicka, 2017).
To give some perspective, black coffee has around ~95 mg of caffeine, and green tea has around 35 mg (with all the same conditions and caveats as white tea of course, it can vary a lot!).
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If you have no idea what these different types of white tea are, don’t worry! We’ve covered that here: White Tea: An In-Depth Introduction to this Elegant Tea
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You would expect Silver Needle to have the highest levels (being the buds), and the levels to taper off as we progress down the list, but as you can see it varies considerably due to variations in individual tea. I have compared the three main studies of white tea caffeine levels, and then given the average across them.
All three studies measured caffeine levels using 1 gram of tea (about 1 tsp, depending on how ‘fluffy’ the tea is). Some of the studies measured caffeine per 100 ml (3.38 fl oz); I have converted the results to 8 fl oz for ease of comparison. This is the standard coffee mug size, if that helps!
In Czernicka’s study, interestingly,, they used three different Silver Needle white teas, and came up with three very different measurements. Demonstrating how much it can vary!
|
Tea Type |
Caffeine Level (8fl oz) |
Average Caffeine (in 8 fl oz) |
||
|
Yang, 2001 |
Czernicka, 2017 |
Chen, 2007 |
||
|
Silver Needle |
61 mg |
34.07 mg (100 ml) = 80.6 mg (8 fl oz) 30.06 mg (100 ml) = 71.11 mg (8 fl oz) 13.11 mg (100 ml) = 31.01 mg (8 fl oz) |
15 mg |
51.74 mg |
|
Bai Mu tan |
57 mg |
38.33 mg (100 ml) = 90.68 (8 fl oz) |
39 mg |
62.22 mg |
|
Gongmei |
48 mg |
-- |
-- |
48 mg |
|
Sowmee |
38 mg |
28.86 mg (100 ml) = 68.27 (8 fl oz) |
-- |
53.13 mg |
What’s really fascinating about the above results is how big a difference leaf size makes:
- Silver Needle is made of tea buds, which have by far the highest caffeine content of any part of the tea bush.
- Bai Mu Tan is a mix of older leaves and tea buds, which might imply lower caffeine but Bai Mu Tan is usually brewed in higher temperature water, often near boiling, and has a lot of broken leaves (and twigs usually!).
- Sowmee is also higher than Silver Needle, despite being made almost entirely from older leaves. But - they are usually broken, which allows more caffeine out of the leaf and into the cup.
Why does the myth of low caffeine in white tea continue?
Lots of reasons!
- Measuring caffeine is tricky, as there are a lot of variables. You can see the range across the studies on white tea in the table above, and these are specific types of white teas let alone black tea in general.
- The USDA gives lots of different caffeine levels, and it’s almost plucking a number from thin air. It’s really challenging to have consistent results when there are so many variables that change the caffeine levels!
- It feels like it should have lower caffeine due to the calming antioxidants
- It looks like it should have lower caffeine vs the darker “more substantial” cup you see with black tea
- Black tea seems like coffee’s cousin, it’s richness in the mouth makes you think “stronger”
- Loads of blogs, tea shops and teaheads continue to say white tea has low caffeine for the above reasons, which perpetuates it (we used to think this too years ago before we got into tea!)
- Caffeine in the leaf does not always mean caffeine in your cup, which further complicates things
A Note From Elizabeth...
We hope this blog was interesting and informative, and although no one will memorise mg of caffeine by tea, you can take away from the essential concepts like leaf size / surface, brewing temperature and length, and overall which tea leaves have more caffeine.
This will help you decide which tea is for you, and might interest you in experimenting with your tea! Try your white or green tea at different points from 140F (60C) to 203F (95C) and see if you find a difference, but don’t risk it too late into the evening!
Fun fact: Most caffeine dissolves into your water within the first 30 seconds, so second brewings of your tea leaves have far lower caffeine levels. This is a handy way of reducing your caffeine intake should you so wish!
Questions? Thoughts? Let me know in the comments below or on our IG @MatchaAlternatives
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Punchy mint takes centerstage, with a reassuring background of strong, smooth Sowmee white tea ~ Read more: Caffeine's Impact on Fasting & Fasting from Caffeine: What You Need to Know |
Blueberry Lemon Cake White Tea Smooth and sweet, like a summer cake, but without losing the delicacy of the bai mu tan white tea base ~ Read more: |
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Disclaimer
All of the information regarding the herbs, botanicals, minerals, vitamins, etc., is information drawn from traditional use data or academic research and should be regarded as such. If you, the reader, has a health or medical concern, please consult your healthcare professional. The information found here is not meant to diagnose, treat, prescribe or cure and has not been evaluated by the FDA. This information is for educational purposes only.
Caffeine in White Tea References & Further Reading
The Caffeine Molecule image, Encyclopædia Britannica, Inc. Access 15th Jan 2022. https://www.britannica.com/science/caffeine
Britannica 2021, The Editors of Encyclopaedia. "caffeine". Encyclopedia Britannica, 5 Nov. 2021, https://www.britannica.com/science/caffeine. Accessed 30 January 2022.
Britannica 2020, The Editors of Encyclopaedia. "alkaloid". Encyclopedia Britannica, 20 May. 2020, https://www.britannica.com/science/alkaloid. Accessed 30 January 2022.
New Scientist, Karina Shah, Accessed 30 January 2022. https://www.newscientist.com/definition/caffeine/#ixzz7JSp73vps
IMCMNR, 2001. Institute of Medicine (US) Committee on Military Nutrition Research. Caffeine for the Sustainment of Mental Task Performance: Formulations for Military Operations. Washington (DC): National Academies Press (US); 2001. 2, Pharmacology of Caffeine. Available from: https://www.ncbi.nlm.nih.gov/books/NBK223808/
McBane, D, 2021. White Tea Caffeine Content Is Not Lower Than Other Teas. Let’s Drink Tea. https://www.letsdrinktea.com/white-tea-caffeine-content/
Yang Weili, Xiao Wenjun, Deng Keni, 2001. 杨伟丽，肖文军，邓克尼. 加工工艺对不同茶类主要生化成分的影响[J]. 湖南农业大学学报：自然科学版，2001，27(5)：384-386. Effects of processing technology of different teas on the main biochemistry components[J]. Journal of Hunan Agricultural University: Natural Sciences, 2001, 27(5): 384-386. (in Chinese with English abstract). https://oversea.cnki.net/kcms/detail/detail.aspx?dbcode=cjfd&dbname=cjfd2001&filename=HNND200105016
CHEN Xiao-qiang, YE Yang, CHENG Hao, YIN Jun-feng, SUN Cheng, 2007. Comparative Analysis Of Theanine, Caffeine And Polyphenolic Constituents In Green Tea, Black Tea And Puer Tea. Tea Research Institute of China Academy of Agricultural Sciences, Key Laboratory of Chemical Engineering, Ministry of Agriculture, Hangzhou 310008, Zhejiang, China. http://en.cnki.com.cn/Article_en/CJFDTotal-SPYK200712046.htm
UoU, 2004. Caffeine Content Of Popular Drinks. University of Utah Math Department. 2004. https://www.math.utah.edu/~yplee/fun/caffeine.html
Rate Tea, 2018. White Tea and Caffeine - Myths and Reality. RateTea.com https://ratetea.com/topic/white-tea-caffeine/59/
Qiao, C., Xu, B., Han, Y. et al. Synthetic nitrogen fertilizers alter the soil chemistry, production and quality of tea. A meta-analysis. Agron. Sustain. Dev. 38, 10 (2018). https://doi.org/10.1007/s13593-017-0485-z
Takeda, Y. (1994): Differences in Caffeine and Tannin Contents between Tea Cultivars, and Application to Tea Breeding. JARQ 28, 117-123.
Wartenberg, L, 2019. How Much Caffeine Does Tea Have Compared with Coffee? Healthline. https://www.healthline.com/nutrition/caffeine-in-tea-vs-coffee
Chin JM, Merves ML, Goldberger BA, Sampson-Cone A, Cone EJ, 2008. Caffeine content of brewed teas. J Anal Toxicol. 2008 Oct;32(8):702-4. doi: 10.1093/jat/32.8.702. PMID: 19007524. https://www.pkdiet.com/pdf/Caffeine%20BrewedTeas.pdf
Czernicka, Maria & Zaguła, Grzegorz & Bajcar, Marcin & Saletnik, Bogdan & Puchalski, Czeslaw. (2017). Study of nutritional value of dried tea leaves and infusions of black, green and white teas from Chinese plantations. Roczniki Panstwowego Zakladu Higieny. 68. 237-245.
Elisabetta Damiani, Tiziana Bacchetti, Lucia Padella, Luca Tiano, Patricia Carloni, 2014. Antioxidant activity of different white teas: Comparison of hot and cold tea infusions. Journal of Food Composition and Analysis 33 (2014) 59–66.