Esophogeal Cancer and Hot Tea?

Here's a new one: eating hot foods and drinking hot beverages, including tea, increases your risk for esophogeal cancer. Apparently letting your tea sit for a while so it cools down negates this increased risk.

In the case-control study, risk for esophageal cancer was increased for drinking hot tea or very hot tea vs lukewarm or warm tea. Risk was also significantly increased for drinking tea 2 to 3 minutes after pouring or less than 2 minutes after pouring vs drinking tea at least 4 minutes after being poured. Responses to the questions about temperature at which tea was drunk agreed strongly with interval from tea being poured to being drunk.

"Drinking hot tea, a habit common in Golestan province, was strongly associated with a higher risk of oesophageal cancer," the study authors write.

http://cme.medscape.com/viewarticle/590589

Basically, the article says the type of cancer linked to hot beverage consumption is the same type typically caused by smoking or excessive alcohol consumption. Smoking and too much alcohol damage the cells lining the esophagus, so if your tea is too hot, it'll do the same thing and possibly cause the same kind of cancer.



Other resources:

http://www.ncbi.nlm.nih.gov/pubmed/15151616
http://www.ncbi.nlm.nih.gov/pubmed/17273005

What not to put in tea (with alternative suggestions)

Don't put diesel fuel in your tea.

Do put water in your tea, and steep for 3-8 minutes, depending on the type and quality of your tea.

Don't put antifreeze in your tea. It may taste sweet, but it'll make you die.

Do put sugar or honey in your tea (or don't, depending on your preference).

Don't put your hand in tea you have just finished steeping. It will scald you.

Do put a spoon in your tea to stir with.

Don't put an aging hippie in your tea.

Do put your tea in an aging hippie.

Don't put abstract concepts involving quanta and probability in your tea.

Do put fruit in your tea (unless you're not into that sort of thing).

Don't put fish in your tea.

Do eat fish with your tea.

Don't put aluminum utensils in your tea (or drink from an aluminum container); it will leech into your tea and possibly contribute to a number of degenerative diseases.

Do put wooden, stainless steel, titanium, stone, ice, and silicon utensils in your tea.

And lastly, don't put anything in your tea you'd be afraid to consume or use otherwise.

Is green rooibos 100 times sexier than red rooibos?

So I was googling some stuff earlier and I happened upon this site, which states, "Green Rooibos has 100 times more antioxidants and 10 times more aspalathin than regular fermented Rooibos."

The latter statement I might buy. The former? Not so much. Green tea has more antioxidants than black tea, it's true, but not 100 times more, and I see no reason to believe that rooibos is that much different.

Unfortunately, there's a lot of conflicting information on the internet, as I've mentioned before. Some people claim green rooibos has more antioxidants than any type of infusion. Some say the green variety is 40 times as good for you as the red variety (also a very doubtful claim). It can be hard to sift through all the misinformation out there, but fortunately I found something. Not much, but something.

According to the article, green tea comes out on top, followed by green rooibos, red rooibos, semioxidized rooibos, black tea, and oolong tea.

I see two strange things here. Why would semioxidized varieties of tea and rooibos have fewer antioxidants than full oxidized varieties? I admit I'm not a scientist, but everything I've read has said oolong tea has a higher antioxidant ability than black tea.

Green rooibos is fairly new to the market, so there understandably isn't as much research on it as there is green tea. Hopefully in the next couple years this issue will be resolved, if only because it'd be nice to know where rooibos stands in comparison to tea. Until then, though, it tastes great, is good for you, and has no caffeine or tannins, so drink up.


EDIT: I caught an error as I was scanning through this just now—green tea doesn't actually have more antioxidants than black tea, it just has more powerful antioxidants. The oxidation process changes the chemical structure of the polyphenols present in green tea, but it doesn't remove them. More on this later.

Tannins

A number of years ago I went to a Chinese restaurant with a friend, and at this particular restaurant the first thing they do after bringing you a menu is bring you a pot of hot Chinese black tea. I've always loved it, and before I got into tea I thought it had to be something radically different because none of the bagged teas (which are almost always Indian tea) I'd tried tasted as smooth and non-astringent as it. Now I realize it's a rather weak, flavorless cup of tea, but I digress.

Anyway, this friend did not drink tea. He was Mormon, so that was the reason why, but he attempted to justify it by this line of logic: tea has tannins, and tannins are used to tan leather, therefore tea must tan your insides. A lot of people have this misconception, or at least the part where tea contains tannic acid, the same substance used to tan leather.

It does not. Tea does contain tannins, which are a diverse group of polyphenols, but not tannic acid, which is extracted from oak leaves and has an entirely different chemical structure. Not all polyphenols are tannins, but all tannins are polyphenols, and as we all know, the best constituents of tea are polyphenols. Basically, a tannin is any polyphenol that shrink proteins or bind them together and cause water to evaporate off them. Any chemists or biologists reading this should correct me if I'm wrong—I got that last bit off Wikipedia earlier today.

Tannins are responsible for the astringency of low-quality or oversteeped teas, basically. Most fruits or veggies that causes your mouth to pucker up and feel like it's been dried out are high in tannins. This is why tisanes like rooibos or chamomile don't succumb to this effect when you steep them for a long time: no tannins. If teas didn't have tannins, it's very likely there wouldn't be concept of second and third steepings, because we'd just steep them as long as wBlogger: Tead Off: The Tea Blog - Create Poste wanted. White tea is the exception here, as it is relatively low in tannins, though lower quality varieties will get bitter if you steep them for too long, and most will become at least a little astringent if steeped for more than 5-8 minutes.


Tannins are good and bad for you. They are not poisonous like tannic acid, and there is absolutely no way you could ever tan leather using tannins from tea or any of the other foods and beverages we regularly ingest. First, the good, because that's what we all want to hear:

• Tannins cause the lining of the intestinal walls to constrict, making them a good remedy for diarrhea, in addition to a number of other inflammatory bowel conditions.
  
• They also help heal wounds by forming a protective layer around the abrasion and by helping stop bleeding.
• Tannins are anti-microbial, and have also shown antiviral and anticancer potential in tests.

And now the bad:

• Tannins inhibit the body's ability to absorb minerals such as iron. This can lead to anemia. If you eat a lot of red meat you probably don't have to worry as iron from animal sources absorbs very readily, though you should be worried about other things instead if you're a red meat freak...
• Some people may have gastro-intestinal troubles if they ingest a lot of tannins.
  
• Tannins have been linked to cancer, though tea has not been, so don't worry about this one unless you take a lot of astringent herbs

Basically, moderation is good. If you're worried about anemia or other mineral deficiencies, just don't drink tea while you eat (but if you've heard adding milk keeps the tannins at bay you've been lied to—milk does nothing and may even prevent your body from utilizing the tea's antioxidants). Or add some lemon juice or vitamin C to your tea.

In any case, the most compelling argument for tannins being either benign or benevolent is the fact that tea is the world's oldest beverage other than water, and that if it were actually harmful we'd probably know about it by now. So drink up.

Tea's Dark Side

Okay, it's not much of a dark side, I'll admit, and it's not so much the tea plant's fault as it is our own. Plants breath the air and suck nutrients out of the ground, so it's only natural that they can also such up foreign matter and toxins. For this reason you generally don't want to pick berries or harvest plants that are near roads or industrial centers. Tea, unfortunately, is no exception.

A lot of places online will tout tea's fluoride content as a positive. "Oh, it protects your teeth!" they'll say. And why? Maybe because they're stupid, maybe because they're tea fanboys/fangirls, or maybe because they're trying to sell a product. Well, it may be true that the fluoride content of tea leaves helps protect your teeth. But you are drinking that tea, not gargling and spitting it out, so any fluoride that touches your teeth is also going to run its course through your gut. Ingest too much fluoride and you run the risk of developing fluorosis, a nasty condition where bones and joints fuse together. If left untreated it will cripple you and put you in immense pain. Not to mention all the other nasty things fluoride can do to you. I won't get into the fluoridated water debate, but I will say this: many bagged teas have fluoride levels well above that of tap water. Instant tea is the worst, but I imagine if you drink that stuff you aren't reading this blog right now.

Check it out. Not so good, eh? But it's not all bad. First of all, fluoride and other toxins accumulate over time, so if you drink tea made of younger buds you will not be getting as much in your system. If your tea comes from a remote, unpolluted place, same deal. The higher quality the tea, in general, the less fluoride in it. White teas tend to have the least because they're harvested the earliest. Black teas tend to have the most because they're harvested the latest.

Most people don't experience any problems or develop fluorosis, anyway. But if you are worried (and I'm truly sorry if it's my fault), you can use non-fluoridated water when you brew your tea. I'm lucky because we don't put fluoride in our water (or much of anything—our water quality is really high), so tap water is fine for me. But if your tap water is fluoridated, use distilled water. And drink higher quality teas. Not only will it be better for you, but it'll taste better, too. I guarantee it.

It's also important to note that rooibos has considerable fluoride in it as well (as far as I know honeybush doesn't, however).

Republic of Tea - Golden Yunnan

For hardcore tea connoisseurs such as myself, Republic of Tea is not the ideal choice. Although I do drink it often at work (teabags—loose leaf tea is a pain in the ass to deal with in the break room), I don't typically drink it at home. I still don't, honestly, but this deserves special mention simply because it was my introduction to what is now my favorite black tea.

That's right, Golden Yunnan. This is a tea that catches most habitual black tea drinkers unaware upon the first sip, as most people are only familiar with Indian black teas, which tend to have a very strong taste and can go bitter easily if oversteeped. Even Darjeeling, which is considered to have a milder, more delicate taste, is pretty friggin' strong compared to most Chinese teas. But Yunnan teas are some of the very best. Yunnan province has some of the oldest tea bushes in the world and provides a number of the finest teas you can get.



My first experience was heavenly. I bought this canister on a whim when I saw it in the clearance section (though it still cost more than most of the other Republic of Tea varieties). I took it home, and the honeymoon lasted about a week. It only ended because I ran out of tea, of course.

Basically, Golden Yunnan tea doesn't become bitter or astringent if you oversteep it, and I certainly did a few times. It has an unoffensive and complex flavor, and while I've read that it often has a slightly peppery taste to it, I've never gotten that. Maybe the crops from the last couple of years have been subpar or something. I have gotten a somewhat tangy, lively cup of tea, however, and Republic of Tea may be a little overpriced and overhyped, but it's still good tea. Just as a side note, this tea is also known as "Golden Needle Tea," and we all know how coveted Silver Needles white tea is... As a rule, if a tea has the word "needle" in its name anywhere, it's a pretty badass tea.

Now I have two very large canisters from Adagio: one of their Yunnan Jig, which is similar to what the Republic's Golden Yunnan is, and one of actual Golden Yunnan, which is made up entirely of the golden tips of the tea buds. Obviously that one fetches a premium over the former. The Jig has a stronger flavor more in line with that of stronger Chinese blacks, while the Golden is milder but more complex. They're still very similar, and it took me a while to really figure out the difference between them, but once I did I set the Jig aside for entertaining guests (or drinking first thing in the morning if I don't feel like Darjeeling).

So in conclusion, thank you, Republic of Tea, for introducing me to a tea I should never have gone without.

Oxidation vs. Fermentation

Just a quick note and nit: when people talk about black or oolong teas being "fermented," they are using the wrong word. There is no fermentation in the production of tea. Fermentation is used in alcohol production and anything else where energy is produced in anaerobic conditions (like in your muscles or compost heap). Tea does not undergo a process like this at all. Tea is oxidized, where essentially oxygen is allowed to change the molecular structure of the leaves and produce black and oolong teas (and even white teas, sometimes).

I just thought I'd clear the air on this. It's been bothering me lately. I received a catalog in the mail for an herb company I often buy from, and they also sell some tea products. They had a jasmine green tea and said the jasmine leaves were fermented with the tea leaves. First of all, green tea isn't oxidized, but since I like the company I can forgive them that specific offense. But the usage of the term "fermentation" is a crime committed by many a tea retailer, and I will not stand for it!

Green Tea Extracts

You probably shouldn't take them. For several reasons.

1) The tea used in green tea extracts is of the lowest quality. Yes, you'll get considerable amounts of antioxidants, and yes, the taste doesn't matter when you're swallowing a pill. But the lowest quality tea also has the highest level of toxins, such as fluoride, aluminum, and whatever else the soil has been exposed to.

2) Taking a pill every morning isn't as effective as drinking several cups of tea over the course of the day. Most of the antioxidants in tea get flushed out of your system, so drinking 6 cups of tea over the course of 12 hours will keep more antioxidants in your system for a longer time than taking one pill with the equivalent of 6 cups of tea once a day.

3) Too much of a good thing is bad. Your kidneys and liver filter the polyphenols in tea out of your bloodstream. I could explain why your body does this, but that would take research I don't feel like doing right now, so I'll post on it later. Anyway, there's an upper limit to how much of these antioxidants are good for you. Some green tea extracts are equivalent to ten, twenty, forty, fifty, or more cups of tea, and that is not good.

Check it out.

It's partly our culture that decrees if something is good, then more of it must be better. I haven't found any studies that have shown liver or kidney damage can be caused by drinking tea alone, so it may just be that the supplements do this by introducing too many polyphenols into the body at one time, but then I doubt there is anyone who's ever drank 50 cups of green tea a day on a regular basis.

I've found several websites that sell these supplements, and they tend to say things along the line of, "there's no such thing as 'too much' when it comes to green tea." If you see one of these ridiculous bullshit claims, just remember that they are trying to sell you a product, not make you live longer.

Ditch the supplements and just drink tea. Or if you're savvy with herbal rememedies and like the convenience of supplements, make your own extracts! Just boil the tea in a pot like you normally would, remove the tea leaves and let the tea sit on low heat for several hours, and wait for all the water to evaporate off. The powdery residue on the bottom of the pot is your extract. Just remember how much tea you put into the pot in the first place so you don't accidentally megadose on green tea extract and make yourself sick.

Rooibos and Honeybush: the Story Continues

Okay, so now you know all about rooibos and honeybush. Or do you?

Like black tea, rooibos and honeybush are oxidized, which gives them their dark red color and depth of taste. They are prepared like this because while South Africans have been enjoying both of these plants for centuries (if not millennia), the British are the ones who introduced them to the global market, and they thought they'd treat it like black tea (as it is often considered a tea substitute).

Well, if you don't oxidize the plant what do you get? Green rooibos and green honeybush, just like tea. I myself just tried them about a week ago, and I was pretty impressed.

First off, as with tea, the green varieties of rooibos and honeybush contain a much higher level of antioxidants. The green varieties are fairly hard to find (green honeybush especially so), so there understandably isn't an awful lot of research about these antioxidant levels, so don't buy into any hype about either of them being better for you than green tea.

Green rooibos

Now, green rooibos looks an awful lot like lemongrass. It tastes slightly vegetal, but not nearly as much as green tea does, and it retains a slightly fruity and tangy flavor. Interestingly, it has a faint licorice-sweet aftertaste (not the taste of licorice, but the sweet aftertaste you get when chewing on some of the root), which makes me wonder if it contains similar sweetening compounds as licorice root. I like it and recommend it. Just judging from my experience, it seems to have a more marked sedative effect than oxidized rooibos, so you probably shouldn't drink a quart of the stuff in one sitting your first time like I did just now.

Green honeybush, which isn't very green at all

I expected green honeybush to taste very similar to green rooibos, but it did not. First, the smell. Green rooibos smells like dried plant. Green honeybush, however, smells like awesome. It has a very tangy, fruity aroma—if I dare say, it smells sexy. The taste followed suit. It seems less sweet than oxidized honeybush, but I think it's just because the green variety is much tangier and acidic tasting (not TOO acidic, just MORE acidic). I find it best to subdue this beast with a dab of honey. What results is a really good tisane without the vegetal notes of green rooibos (but also, unfortunately, without a detectable licorice-sweet aftertaste).


You may be tempted to treat these like green tea and use water that isn't boiling. I've only used boiling water. It tastes fine, and the reason you use cooler water with white and green teas is because you'll fuck up the flavor by making the tea release all kinds of bitter tannins and by destroying more delicate flavor compounds. Rooibos and honeybush have no significant tannin levels, and if they have delicate flavors that require lower brewing temperatures, I doubt you'd notice them over the fruity and tangy flavors so prominent in them—ESPECIALLY if you brew them for 8+ minutes (which I recommend).

I bought my green rooibos and honeybush from Upton Tea Imports. I've found green rooibos from a couple other companies, but not green honeybush. Their teas are pretty damn high quality so far, I've found (I am not affiliated in any way with the company), so if you want to try either of these tisanes, you can't go wrong with them.

Honesty and Morocco

It may seem like I enjoy ALL teas on this site. After all, I haven't posted a bad review or anything... Not true. I don't like green tea. I dislike the vegetal, grassy taste and the bitterness that ensues if my timer doesn't go off while I'm steeping it (which it always does—it's a passive-aggressive timer that only alerts me when I'm brewing something that can be oversteeped like rooibos or white tea).

However, I DO love Moroccan Mint green tea, which is named so apparently because Moroccans like green tea with mint (as if no one else does). In fact, this was the first tea I ever truly enjoyed without having to put a ton of sugar into it. Honest Tea, in fact, way back in 2002 before they were bought by Coca-Cola. It's great tea and so far is the only brand I've found that sells actual tea, not sugar water with tea in it (although their new offerings keep getting sweeter and sweeter). On an unrelated note, I really miss their Kashmiri Chai. It was about the only chai tea I liked cold. And boy, was it good... Anyway, I still love their Moroccan Mint tea, although the formula has changed several times since I first drank it. They've switched between cane juice and honey as sweetener, China green tea and gunpowder green tea, and proportions. It's a bit fuller flavored these days, which is fine.

But it costs $6.00 for half a gallon, and in summer I will drink that half-gallon in a day or two. So for a few years now I've been trying to replicate their formula. It doesn't help that they keep changing it, but I've found one that works pretty well. The directions below are for a gallon batch, so adjust according to your needs. You should probably have a very large infuser for this. The dry material shouldn't take up more than half the space in it or your tea will suffer.

My ingredients are:

1 gallon of distilled water (I never actually use distilled water, but I bet if I did it'd be awesome)
6 heaping tablespoons of green tea (actual tablespoons, not the official measure)
4 tsp. peppermint leaf
2 tsp. spearmint leaf
3/4 tsp. lemon juice
6 tbsp. (the official measure, not actual tablespoons) honey


I usually do two infusions for a total of two gallons of tea: one for 3 minutes, and the second for 5 or more. You don't want boiling water, as this is green tea, and the second batch WILL be much lighter than the first, so halve your lemon juice for that one or it'll be more citrusy than minty or green tea-y.

I usually use Dragonwell green tea, but I've gotten good results with Sencha and Gyokuro as well. Stay away from the gunpowder green tea. It is inferior. My last batch used Adagio's Emerald Needle green tea—the tea smells divine and tastes pretty good on its own for a green tea. With the mint it tastes a bit fruity. Maybe too much so.

Also, try substituting lime juice for lemon juice. It tastes less like the Honest Tea version I've tried to copy, but it's very good. You can also just use citric acid if you want, but you'll need such a small amount and every time I try I invariably fuck it up and make the tea way too acidic.

Anyway, once you have it steeped, it should keep in your fridge for a couple weeks at least. I've never had a batch go bad on me within that time frame (or ever, actually, because they don't typically last past that timeframe).


I don't actually like this version hot very much. I prefer straight peppermint leaf with my green tea when I have hot Moroccan Mint. But you can drink it however you please.

Honeybush Tea

I've been on a big rooibos and honeybush kick lately, as sleep is important in my life, and sleeping is about the only thing tea won't help you with.

Now, I've known about rooibos for a long time. Honeybush, however, I've only found out about more recently.

Honeybush from Adagio tea—as you can see I've already used most of it

Honeybush is often lumped in with rooibos when you go to buy it. It brews a similar color, the dried plant looks like a coarser version of rooibos, and it even tastes somewhat similar. In addition, from what I've found online, it's even somewhat similar chemically, containing many antioxidants (but not aspalathin—that is unique to rooibos) and grows in South Africa as well. Unlike rooibos, however, it is not cultivated, so if you drink honeybush tea, you're drinking wildharvested tisane, not something grown on a plantation. This has its benefits (no pesticides) and its drawbacks (no quality control), which I won't get into here.

Like it's name implies, honeybush tastes sweet. Sweeter than rooibos. You don't need to add any sweetener to it—it tastes like it already has a small dollop of honey in it. And like rooibos, it's slightly fruity and tangy. I prefer it, taste-wise, to rooibos.

Basically, the same rules apply to honeybush as they do to rooibos: steep for a long time, drink as much as you want, expect to become immortal, etc. Just bear in mind that you'll pay a premium for honeybush tea over rooibos because it's rarer.

Rooibos

A few years ago (right around the yerba mate craze, I believe) there was another tea alternative that rose to prominence, with all sorts of lofty and baseless claims: rooibos. Also known as "red tea," it has nothing to do with real tea. It's a plant that grows in South Africa and brews a dark amber cup with a slightly sweet, tangy, fruity taste.

Jasmine rooibos tea from Adagio teas—good stuff

I'm not going to knock it. Some sources claim it has more antioxidants than green tea. This may be true or it may not be—rooibos does have a bunch of antioxidants, including one unique to it: aspalathin. Not much research has been performed on rooibos so this may not matter at all—not all antioxidants are equal, and the ones in rooibos may not interact with the human body in the same way as those found in tea. Still, rooibos is caffeine free, tastes good, and studies have shown it IS good for you (if nothing else, it contains several vitamins and minerals, including potassium and magnesium), so you may as well drink it if you like it.

I myself drink it most nights. In addition to having no caffeine, rooibos also acts as a mild sedative. For an insomniac like myself this makes it all the more attractive. Hell, it's nice to have at work, too—helps me deal with all the stress, although some people react more strongly to it and may be a little more sedated than they'd wish.

Rooibos has an extremely low tannin content, so it won't get bitter if you steep it for a long time. In fact, I recommend you steep it for upwards of ten minutes. It pairs well with flavors, too—try a good chaibos (that's chai made with rooibos) and you'll think it's black magic.

Rooibos steeped for 8 minutes

Interestingly, rooibos is also of use in cosmetic products. Like green tea, rooibos helps protect and heal the skin when applied topically, and acts as a mild sunscreen. If you make your own lotions or soaps, give it a try instead of or in addition to green tea. Just remember it'll impart a reddish hue onto whatever you make.

Devil's Brew

I'm up late, I'm tired, and I still have shit to do before class tomorrow. However can I stay up late enough to finish this term paper without crashing on caffeine mere hours later?

I know! Devil's Brew™!

Here's the plan: come spring time, I'm going to go out and harvest some tender Devil's Club (Oplopanax horridus) shoots and possibly roots, dry them, mix with yerba mate (I know I just published a post on the horrors of it but I'm still doing it) and dried blueberries (also harvested locally), and then enjoy.

But why Devil's Club, you ask? Why sir, let me enlighten you! Devil's Club is also sometimes called "Alaska Ginseng." You see where this is going. Devil's Club is related to the American Ginseng plant and has been used medicinally by Native Americans for quite some time. Supposedly it enhances mental clarity/ability and acts as a stimulant like ginseng is supposed to, though in reality Devil's Club hasn't been proven to do so. Still, there's no harm in trying, and it HAS been show to be effective in treating diabetes.

And why blueberries? Because Devil's Club tastes like shit.




I hope to post on a variety of local infusions and concoctions this summer, as I intend to harvest everything from nagoonberries to fireweed leaves. Being able to go out and harvest uniquely Alaskan (or west coast) plants and fruits is pretty neat—I'm able to create many things you could never find in a store. The above idea I've had milling around in my head for a while, but you can't use the Devil's Club shoots after that initial tender stage where the spines aren't hard yet, and I dropped the ball on getting them last spring. This spring will be different, but for now I need to sleep. No Devil's Brew for me (or term paper, thank goodness).

All About Mate (Yerba)

Man, I haven't posted in nearly 6 months. Kinda pathetic, eh? I'd make up some excuse about school and work keeping me too busy, but honestly it's just that I'm lazy. And maybe a little busy with work and school. I'm going to try to post semi-regularly again, but no guarantees (and CERTAINLY no set schedule!).

Anyway, a few years ago a drink called "yerba mate" burst into the mainstream and was touted as a miracle drink, with people claiming it provided a super-duper energy burst (with no ill effects) and that it was better for you than even green tea. I haven't seen it around so much lately, but many are still a little confused about how it stacks up to tea. I'll attempt to illuminate the world (or at least my readers--if any of you are left) below.





Yerba mate is a plant that grows in South America and is drunk in most of the countries there. I personally don't like it, as it tastes very vegetable-like and sort of grassy like green tea, but some people like that kind of thing. It's actually pretty nutritious and contains a lot of vitamins and minerals, as well as antioxidants and such (though just about EVERY plant contains antioxidants--antioxidants serve to protect the plant from the sun's rays). And because the people in South America are clearly still alive, mate can't be poisonous or toxic or anything.

Even more compelling is the fact that while yerba mate does contain a form of caffeine, it acts differently in the human body. It stimulates without making you jittery, as it affects muscle tissue moreso than the nervous system (which is what coffee and tea affects).

However, as far as containing more antioxidants than green tea (or more effective ones), mate falls short. It's good for you, but it's not green tea. I don't know how it stacks up to rooibos or black tea (there doesn't seem to be any literature), but green tea still reigns in that department. Also, yerba mate has been connected with several forms of cancer, including oral, esophageal, stomach, bladder, and lung cancers. There isn't any conclusive evidence to show that it actually causes these cancers, but I'd recommend enjoying it in moderation or abstaining completely from it until there's more data.



Other resources:

http://pixiemate.com/mate-studies.html
http://www.mayoclinic.com/health/yerba-mate/AN01774