I have heard it since I was a kid: Drink plenty of fluids means water. It doesn’t include caffeinated beverages like tea. That statement didn’t come with much explanation when I was little. Later, Mom explained that only clear liquids count. I couldn’t figure out why 7-Up was okay when I was sick, but iced tea wasn’t. When I got married, my wife explained to me that it was the caffeine that caused the problem. Caffeine, you see, is a diuretic. That means it makes you pee. The more you drink, the less hydrated you are. This explanation has always bothered me, but I never went to the trouble to research it for myself.
I came across a paper entitled Caffeine ingestion and fluid balance: a review, by R.J. Maughan and J. Griffin. They reached the conclusion that large amounts of caffeine consumed by people unused to caffeine can, indeed, cause dehydration. On the other hand, people who regularly drink caffeine can consume quite a bit of it without a problem. To quote their results directly:
“The available literature suggests that acute ingestion of caffeine in large doses (at least 250-300 mg, equivalent to the amount found in 2-3 cups of coffee or 5-8 cups of tea) results in a short-term stimulation of urine output in individuals who have been deprived of caffeine for a period of days or weeks. A profound tolerance to the diuretic and other effects of caffeine develops, however, and the actions are much diminished in individuals who regularly consume tea or coffee. Doses of caffeine equivalent to the amount normally found in standard servings of tea, coffee and carbonated soft drinks appear to have no diuretic action.”
In conclusion, when I am sick and/or dehydrated, I may feel free to drink my tea.
But wait! It gets better! I came across another paper entitled The effect of drinking tea at high altitude on hydration status and mood by D. Scott, J.A. Rycroft, J. Aspen, C. Chapman, and B. Brown. This is an absolutely awesome study, simply because they performed it at Mt. Everest base camp. It’s not a statistically valid sampling (only 13 people participated), and I’m not sure how valid a study performed at 17,500 feet altitude is for us lowlanders at 5,500 feet. But, hey, it was done at Mt. Everest base camp, and the procedure they used in the study does seem reasonably rigorous.
To put the results in their own words:
“The study shows therefore that even when drunk at high altitude where fluid balance is stressed, there is no evidence that tea acts as a diuretic when consumed through natural routes of ingestion by regular tea drinkers, but that it does have a positive effect on mood.”
Immediately upon reading this, I began putting together a list of people that might benefit from a few cups of tea. There are even those rare occasions when my own mood is not particularly sunny and bright. Not many, of course, but I must be prepared and have some good tea set aside for those moments.
Alas, upon closer reading I discovered that the “positive effect on mood” is actually “subjects reporting reduced fatigue when tea was included in the diet.” Oh, well. If you think about it, tea has long been touted as a good relaxant, so this particular finding makes sense.
With my hopes for a worldwide cure for bad moods rudely dashed, I shall have to fall back on tea as a way to hydrate and reduce fatigue. Sounds like the perfect thing to have along on a hike or at the gym. Surely that’s no surprise to my tea-loving readers!
Several times in the last couple of years, people have come in to the tea bar and asked if we have kombucha. The first time, I did a quick Google search, looked at the process required to brew it, and said no. After the third time, I figured I should look a bit deeper into this phenomenon. Conveniently enough, the Healthy Beverage Expo was held in Las Vegas alongside the World Tea Expo (the largest trade conference in the tea business) , so I was able to sign up for a kombucha seminar to go along with all of the tea seminars I was taking.
I learned quite a bit in the seminar, although virtually none of what the instructor covered was applicable to a tea shop serving freshly-brewed drinks. Almost everything she talked about applied to RTD (ready-to-drink) bottled beverages, which really doesn’t interest me. We don’t serve bottled tea or soda — or even bottled water — so RTDs didn’t really interest me much. I was there to learn about fresh beverages.
Following the seminar, I did some further research and made an informed decision about selling kombucha in my tea shop. Here is my thought process:
What is kombucha?
Kombucha is a fermented drink made from a fairly heavily sweetened black tea (about 1 cup of sugar per gallon of tea), although other types of tea can be used as well. A symbiotic culture of bacteria and yeast known by the acronym “SCOBY” is placed on top of the tea blend. It grows into a gelatinous mass on top of the tea as it ferments the sugars in the tea mixture. After a week or so, the freshly grown bacteria/yeast mat can be separated out into a new SCOBY for the next batch, and the liquid can be drawn off to drink.
It’s really good for you, right?
First of all, I don’t select teas based on health claims. I select teas that taste good. At times, those goals align, but I’m frankly underwhelmed at the amount of hard data backing most herbal health claims, and I’m not going to pass on health claims to my customers unless they are backed up by honest-to-goodness, peer-reviewed, reproducible studies — preferably with double-blind clinical studies.
Sitting in the kombucha seminar, I was struck by the PowerPoint slide titled “Health Benefits.” It listed every imaginable ailment from cancer to Alzheimer’s, heart disease to diabetes. The list was absolutely stunning. Before I had a chance to react, someone else in the audience asked what the basis was for this list. The instructor informed us that she had recorded everything her friends, family, and customers had told her. If someone told her they drank kombucha and their gout got better, she’d put gout on the list.
In other words, all of these health benefits were unconfirmed hearsay with no scientific basis whatsoever. A short amount of digging brought me to an article on kombucha by the American Cancer Society. I think one quote from that article sums it up really well:
Available scientific evidence does not support claims that Kombucha tea promotes good health, prevents any ailments, or is works to treat cancer or any other disease. Serious side effects and occasional deaths have been linked with drinking Kombucha tea.
Not exactly a ringing endorsement.
Logistics of kombucha
In a tea bar environment, I have dried leaves with a shelf life measured in months. The few fresh items I need, such as milk, boba pearls, and lemon slices, can either be purchased on a moment’s notice at the grocery store, or made in a matter of minutes. Kombucha requires at least a week to brew, which means if you want to serve it fresh, you need to be very good at predicting demand a week in advance.
If you wish to store and keep it, you have to bottle or keg it, and that takes me back to the RTD issue I opened this article with. If I’m going to serve a bottled beverage, I’d might as well buy it from someone else instead of trying to ferment it myself.
Fermentation leads to another issue as well. The yeast in the SCOBY does exactly what yeast does in beer or wine: it consumes sugars and excretes alcohol and carbon dioxide (CO2). The CO2 provides carbonation, most of which is allowed to escape. The alcohol is another issue. The Federal government puts strict controls over alcohol content in beverages. If you wish to sell fresh-brewed kombucha, you must carefully control and measure the amount of alcohol.
Not only can we not sell beverages to children if they contain more than a fraction of a percent alcohol, but without the proper licenses, we can’t produce alcoholic beverages in the tea bar anyway.
I used to do a lot of homebrewing. I really enjoyed making and drinking my own beer. If I still had all of my equipment set up for the beer, I’d probably brew up a batch of kombucha just for fun. I’m not, however, going to make it in the tea bar because the logistics are complex, it doesn’t fit the business model of freshly-brewed tea, and the health benefits are unsubstantiated.
I read a lot about tea (what a surprise, eh?), and try to carry a decent selection of tea books in my bookstore. When somebody recommended the book 20,000 Secrets of Tea: The Most Effective Ways to Benefit from Nature’s Healing Herbs by Victoria Zak, I decided to give it a look. I confess I was put off by the subtitle, because it sounds more like a book of herbal medicine than a book about tea. Then I flipped the book over and took a look at the back cover. There I saw this:
“An Ancient Chinese Legend: Once there was a man who knew 100,000 healing properties of herbs. He taught his son 80,000 secrets. On his deathbed, he told his son to visit his grave in five years, and there he would find the other 20,000 secrets. When the son went to his father’s grave, he found, growing on the site, the tea shrub…”
Okay, that’s more promising. Especially this line in the next paragraph: “A simple cup of tea not only has the power to soothe and relax but to deliver healing herbal agents to the bloodstream more quickly than capsules, tinctures, or infusions.” That line indicates that they know the difference between tea and infusions/tisanes, and that this book is going to be about tea.
Oh, my, was I wrong.
Page one starts out with a description of the legend of the origin of tea. Chapter one continues on, repeating the story from the back cover and then providing some of the history of tea as a drink. Within five pages, it has transitioned to herbal infusions, and that’s pretty much the end of discussion of the tea plant (Camellia sinensis).
I flipped through the next 220 pages looking for more information about tea (after all, the next 20,000 secrets are all about the tea shrub, right?) and I all found was descriptions of various herbs along with multitudinous health claims about each (more on that in a moment).
I went to the index looking for tea. The index is 15 pages long, normally a good sign in a reference book. Under “tea” I found reference to pages 1-4, mentioned above. Under Camellia sinensis, nothing. Flipping through the alphabetical collection of herbs, tea isn’t even listed. I checked under “black tea” and found a two-page spread in the middle titled “Green, Oolong, Black: the legendary teas.”
Zak begins by repeating the origin legend from page 1, and then proceeds to talk about fermentation (none of those teas are fermented, although black and oolong are oxidized) and rates the three styles in order of “medicinal strength: (green, then oolong, then black). Nowhere does she mention white or pu-erh tea, and nowhere does she define what “medicinal strength” actually means. Obviously, when there’s so little information, it leads to gross overgeneralization. When you use up that little bit of space with statements like “Green tea’s polyphenols are powerful antioxidants are reputed to be two hundred times stronger than vitamin E. It has anticancer catekins (sic), which protect the cells from carcinogens, toxins, free radical damage, and help to keep radioactive strontium 90 out of the bones,” there’s no room left to describe the differences between tea styles, how to properly steep a cup, or any of the other subjects that I expected this whole book to be about.
Incidentally, none of those rather incredible health claims are footnoted, no studies are cited, and no backup data is provided.
All in all, this book is tailor-made for herbalists — especially those that don’t worry much about the scientific basis of their health claims — but pretty well useless for tea enthusiasts.
Today, I received my first shipment of the purple tea that I blogged about back in August. I opened the bag with no preconceptions, as I haven’t read anyone else’s tasting notes.
The leaves look like pretty much any black tea. Not surprising, as the purple tea plant (TRFK306/1) can be prepared using any tea process, and this was oxidized like a traditional (orthodox) black tea. This is a very dense tea. The kilogram bag I purchased was the same size as the half-kilo (500g) bag of Golden Safari (a Kenya black I’ll be writing about soon).
I took a deep whiff, and picked up a slight earthiness to it that isn’t present in the other Kenya black teas I’ve tried. Not as extreme as a shu pu-erh, of course, as there was no fermentation in the process, but enough to distinguish the aroma from a traditional black tea.
Actually, despite my previous comment, I did come in to this with one preconception. Since this is a high-tannin tea, I expected a fair amount of astringency (“briskness,” as Lipton calls it), so I decided to take it easy on the first cup and make it like I make my 2nd-flush Darjeelings: 5 grams of leaves, 16 ounces of water at full boil, and a scant two-minute steep time.
“I did not expect purple, as the anthocyanin that gives purple tea its name doesn’t affect the color of black tea.”
The leaves settled immediately to the bottom of the pot, and I was taken by surprise by the color. I did not expect purple, as the anthocyanin that gives purple tea its name doesn’t affect the color of black tea. But I also didn’t expect the pale greenish tan color that immediately appeared (it later mellowed to a deep black with — you guessed it, a purplish tinge). We don’t have any analyses yet of total antioxidant content, but we know that the anthocyanin does contribute quite a bit.
My first taste of the purple tea was impressive. Rich, complex, and a bit more astringent than you’d expect with only a two-minute brewing time. The earthiness in the aroma comes through subtly in the taste, and there’s a silky mouthfeel that lingers on the back of the tongue.
I figured that there was enough going on in that tea that it could hold up to a second infusion, so I brewed a second cup off of the same leaves. This time I gave it a three-minute steep, and it came out tasting very similar to the first brew, although a bit more pale in color.
“Purple tea is certainly not cheap.”
All in all, I’m pleased and excited to have this new varietal available at the tea bar. Purple tea is certainly not cheap. At $16.00 per ounce, it’s one of the priciest teas on our menu, but I expect it to build a fan base quickly. Our new tea website isn’t quite ready to launch yet (I’ll make a big announcement here when it is), but if you’d like to order some Royal Purple tea, just call the store (406-446-2742) or send an email to gary (at) redlodgebooks (dot) com. We’re ready to ship right away.
UPDATE MAY 2012: Our tea website is up and running, and Royal Purple tea is now available for purchase.
More more information about purple tea, please see my earlier blog post announcing and describing the varietal.
A few days ago, I posted an admittedly rather snarky article on this blog entitled “Coffee vs. Tea: Do your homework, Fox News.” The main subject of the article was Chris Kilham, the “Medicine Hunter” from Fox News. Chris has responded to the article in email, expressing an interest in carrying on a dialog. Here is what he sent me (verbatim, and in its entirety):
Hi Gary- I saw your mistaken response to my segment on FOX, and thought I’d take time out to reply. Having studied coffee and tea deeply for decades, and having read thousands of pages of science on both, I stand by the claim that coffee is more potently antioxidant ounce per ounce. More Americans do drink black tea rather than green, the fermenting of tea does degrade the antioxidants, and no, the benefits of coffee are not limited to caffeine. I referred to the work of Astrid Nellig, who compiled over 300 human studies on coffee, not the others you noted. And yes, oxidation is in fact “rusting.” The exact same process occurs to cells that occurs to metal, though metal is not living tissue. I see you leave no place on your blog for intelligent feedback. Good idea. Before you rant off on a tangent, you really should get your science together. I have. Point by point I will be happy to go toe to toe. Enjoy.
First, Chris, I hope it was okay to use the thumbnail picture from your Medicine Hunter website. If you would prefer that I didn’t have it on my blog, let me know and I’ll remove it post haste.
Thank you for responding to my post. I appreciate getting feedback direct from the source, and I know you’re busy. Before going through your email point by point, I’d like to start by addressing the very last issue you raise: that there’s “no place on [my] blog for intelligent feedback.” As I said, I actively encourage intelligent feedback. There’s a place on every single blog post for people to leave their comments. If you’re looking at the front page of the site, it’s a link at the end of the post. If you’re looking at an individual article, it’s a section at the end with two tabs: one to see existing comments and one to leave your own. Please feel free to leave your comments on this or any other post on my blog, whether you agree with me or not.
Now, let’s — as you said — go point-by-point, toe-to-toe. I will quote your email, and then respond.
“Having studied coffee and tea deeply for decades, and having read thousands of pages of science on both, I stand by the claim that coffee is more potently antioxidant ounce per ounce.”
I did not dispute this. I said that I was unable to find meaningful studies regarding flavonoid content that covered multiple types of tea and coffee and various ways of preparing them, so I have no way of disproving your claim. What I did say is, “Flavonols aren’t the only basis for measuring the healthiness of a drink.” I will expand that to say that antioxidants in general aren’t the only things that make a drink healthy.
But if you can show me a study comparing antioxidants in coffee with antioxidants in black, green, white, oolong, purple, and pu-erh tea, I would love to see it. Really. I get that question a lot and I don’t have an answer for it.
“More Americans do drink black tea rather than green…”
I agree with you. In fact, I said “One accuracy point for Kilham” after I verified the claim with FAO’s statistics.
“…the fermenting of tea does degrade the antioxidants…”
Black tea is not fermented. This little piece of misinformation is a pet peeve of mine, and it’s one of the things that prompted me to write the original article. Black tea is oxidized. Fermentation is an anaerobic process. There are fermented teas (a favorite style of mine called shu pu-erh is both oxidized and fermented), but they represent such a miniscule percentage of the tea consumed in the United States that they don’t factor into this discussion. I will continue the discussion assuming you meant to say “oxidized” rather than “fermented.”
I am neither a chemist nor a nutritionist, so you’re going to have to tell me what “degrade” means in this context. You had originally said that they were “lost,” and I responded that “Flavonols aren’t ‘lost’ during oxidation; most (but not all) are converted into different antioxidants called theaflavins, and some convert to thearubigins (which produce the reddish hue of black tea).” Am I wrong?
“…and no, the benefits of coffee are not limited to caffeine.”
Did I say they are? No. I said, “But yes, coffee does contain antioxidants. So, in fact, does tea.” My reference to caffeine was specifically related to your claim that coffee can improve a bad mood. Every study that I found showed that you are absolutely correct. Coffee can improve a bad mood because of the caffeine, which means that tea and Mountain Dew can improve bad moods as well.
“I referred to the work of Astrid Nellig, who compiled over 300 human studies on coffee, not the others you noted.”
I am unfamiliar with Nellig’s work, but if the studies are specifically on coffee, they wouldn’t have pinged my radar (I am uninterested in coffee). If any of Nellig’s studies compare coffee with various types of tea, I’d like to read them, though.
“And yes, oxidation is in fact ‘rusting.'”
This could be an interesting discussion. When I was taking chemistry in school, I would have been smacked for saying that, for example, copper had rusted. Oxidizing was presented as the more general term. All rusting is oxidation, but not all oxidation is rusting. Perusing Merriam-Webster’s dictionary, however, I see that one of the definitions of rust as a verb is “to form rust: to oxidize.” And since the primary definition of oxidize is “to combine with oxygen,” I suppose the first part of your statement is true, based on current dictionary definitions. But do you really want to use “rust” as a synonym for “oxidize” in discussing living organisms? Try this:
Substituting “rust” for “oxidize,” a simplified description of the cardiovascular system would say that you inhale air into your lungs, where oxygen in the air is used to rust your red blood cells. Your arteries and capillaries carry those rusted blood cells to the rest of your body, where the red blood cells “un-rust” as they cause other cells in your body to rust. The de-rusted blood cells then return, via veins, to be rusted once again in the lungs.
Accurate, using those current Merriam-Webster definitions, but it sure sounds strange.
“The exact same process occurs to cells that occurs to metal, though metal is not living tissue.”
Really? To the best of my knowledge, metal is unable to use up oxygen and become un-rusted. Living cells can. It’s not the same process.
The “oxidation vs. rusting” discussion is largely semantic, though, and I don’t want this to turn into a massive debate about free radicals and properties of antioxidants. That wasn’t the point. The point was that your “Q&A With Dr. Manny” article went on a great length about health benefits of coffee without acknowledging that many (all?) of those benefits are shared with various types of tea. The only health benefits of tea that you brought up were antioxidants, and that’s only a single piece of the puzzle.
“Before you rant off on a tangent, you really should get your science together. I have.”
Okay, if you want to call my post a “rant,” I’ll have to agree. It was. But it was by no means “off on a tangent.” It directly addressed your Fox News story, directly on-point. It wasn’t off-topic. And I haven’t seen you call out one single scientific error in what I said (unless you want to call my bullheaded prescriptivism on the definition of “rust” a scientific error).
Last Friday, Fox News ran a “Q&A with Dr. Manny” segment to address the question, “Coffee vs. Tea: Which is Healthier?” Dr. Manny Alvarez handed the question off to someone named Chris Kilham, who I assumed was a scientist or another doctor. I was wrong, but we’ll get to that later.
Kilham began with some general statements (e.g., “For centuries, coffee has been praised for its invigorating properties. And it is truly healthy for you.”) and then stated his opinion: “For the most part, coffee is healthier for you.” Wow. That took me by surprise. Let’s continue and see what kind of well-researched and scientifically-backed justification he puts forth to back that conclusion.
The very next sentence is “The majority of people who drink tea, drink it black, and there’s no question that naturally occurring compounds in coffee are exceptionally good for you.” Really? I’m not sure what the first half of that sentence has to do with the second half, but let’s look at the first half.
I’m going to assume that he meant “most tea drinkers drink black tea” as opposed to “most tea drinkers don’t add milk or cream.” If he’s speaking of the United States, then the Tea Association of the USA backs him up. Their Tea Fact Sheet says that 80% of the tea consumed in the U.S. in 2010 was black tea. Worldwide, statistics vary. Teavana, for example, in the “Types of Tea” section of its website, says that “Green tea is the most popular type of tea, mainly because it is the beverage of choice in Asia.” The Food and Agriculture Organization of the United Nations (FAO) disagrees, however, stating that projected 2010 tea production was 2,443,000 tonnes of black tea vs. 900,000 tonnes of green tea. No offense, Teavana, but I think I’ll go with FAO’s numbers on this one. One accuracy point for Kilham.
Next, he proceeds to say that, “Two large cups of coffee, or 300 milligrams of caffeine per day, can improve a negative mood.” Assuming he’s referring to studies like Rogers & Dernoncourt, Haskell et al, or Peeling & Dawson, it’s the caffeine that has the effect, not the coffee per se. So it not only applies equally to coffee and tea, but you could get the same effect from swilling a two-liter of Mountain Dew.
“Rusting of cells in our bodies? Rusting? And they quoted this guy as an expert?”
His next claim starts with, “Research into the chemical properties of coffee show that a cup of Joe contains potent, protective antioxidants, which inhibit the rusting of cells in our bodies.”Whoa! Back up here. “Rusting of cells in our bodies?” Rusting? And they quoted this guy as an expert? Metal rusts. Cells don’t. Oxygen is the basic fuel that keeps our cells going. Our entire cardiovascular system exists to get oxygen to our cells. *sigh*
But yes, coffee does contain antioxidants. So, in fact, does tea. He proceeds to tell us, “Coffee is especially high in one group of antioxidants, flavonoids.” I attempted to find out whether coffee or tea contains more flavonoids, but there are just too many variables. Suffice it to say they both have plenty.
“And this next paragraph is where Kilham really shows his ignorance about tea.”
And this next paragraph is where Kilham really shows his ignorance about tea: “But if you’re drinking green tea, which is simply tea that hasn’t been fermented, then I would probably have to say that green tea is the healthier drink. It’s rich in flavenols [sic], which are lost when the tea is fermented.” Where do I even start with this?
- First of all, green tea isn’t simply “tea that hasn’t been fermented.” Black tea hasn’t been fermented, either. Nor have white tea and oolong tea. Either Kilham doesn’t know the difference between fermentation and oxidation, or he doesn’t know the difference between black tea (which is oxidized) and pu-erh tea (which is fermented). I’m guessing both, and I’ll henceforth assume he means oxidized whenever he says fermented.
- Next, it’s “flavonols,” not “flavenols.” If you’re going to babble pseudoscience, at least spell the words right.
- Flavonols aren’t “lost” during oxidation; most (but not all) are converted into different antioxidants called theaflavins, and some convert to thearubigins (which produce the reddish hue of black tea).
- Flavonols aren’t the only basis for measuring the healthiness of a drink. Focusing on them to the exclusion of everything else shows that Kilham just didn’t bother to do any research on tea.
He finishes his answer with the standard platitude of the underinformed: “The bottom line: If you’re talking about coffee and black tea, coffee is the healthier choice. If you’re a green tea drinker, green tea is the healthier choice.”
What’s wrong with that conclusion? It oversimplifies the issue and ignores all of the tea styles other than green and black. It doesn’t look at different types of black tea (or variants like the new purple tea from Kenya) or different ways of preparing them.
When I first wrote this response (before Firefox crashed and killed it), I didn’t know who Chris Kilham was. As I mentioned earlier, I assumed he was a medical doctor, researcher, or scientist. When I went to his website, however, I found that he’s a “medicine hunter, author and educator” who “travels the world in search of traditional, plant-based medicines, and works with shamans, healers, growers, harvesters, scientists, trade officials and other plant medicine experts in dozens of countries.” Yep, when I want accurate scientific health information, I go to shamans and healers.
There’s a quote from Dr. Alvarez that says, “I love adventure! That’s why I love teaming up with The Medicine Hunter, Chris Kilham.” Very telling. Alvarez didn’t call Kilham because he loves accurate information or well-researched responses. He called him because he loves adventure! Of course.
I think I’ll have another cup of tea and improve my mood.