>This article is only interesting if you still conflate "green tea" with "natural" and "natural" with "safe".
Green tea _is_ natural. And I conflate "consumed daily by millions of people for thousands of years without incident" with safe. Green tea is not an obscure herb like echinachea or ginko biloba. The idea that putting it in capsules would make it dangerous is not obvious at all. It sounds like magical thinking. So the fact that it is true, and it is in fact dangerous, is actually quite curious to my mind.
Think about the amount of green tea (the plant) that you actually consume in a cup of tea. Even if it's loose tea and you've done a sloppy job, perhaps a few granules.
Now imagine popping a couple of capsules packed with the stuff every day. All of a sudden your intake of something has spiked a few hundred times. It could be cinnamon and you'd have health consequences.
Go to a tea shop and order some Dragonwell, and drink it. Then have a bowl of matcha. You will feel the difference, and it can be a rather alarming one.
Edit: Why that's a big distinction: Your body typically flushes water soluble chemicals fairly easily. It has a harder time with the ones that aren't water soluble, so they tend to accumulate over time. So capsule of tea leaves is probably not the same thing as a cup of tea, from a pharmacological perspective, and theres good basis to assume that it has a lot more ability to hurt you. The same goes for pill version of traditional medicinal teas (echinacea, kava kava, etc.)
Funny that you picked that as an example: https://en.wikipedia.org/wiki/Cinnamon#Toxicity
Same thing: tasty, used for ages, but problematic in large quantities.
The seeds contain 1-3% coumarin. In large quantities, it's toxic to the liver and kidneys, and is banned as a food additive in the US.
As others noted, there are a lot of things we consume in normal doses that if you consumed 10-50x as much would likely cause problems for at least some percent of the people who eat them.
Exactly: try drinking 50x as much water as you normally do. You'll probably die of water poisoning. Is water a poison?
And dosage matters.
No it's not. Green Tea is a manmade liquid made from natural leafs. And those leafs are usually not eaten over a longer timeframe.
I've had a friend who worked at a chemical testing lab for a grocery chain who flat out stopped drinking tea - even organic certified - after running the tests for the client. Every single brand tested positive for quantities a trained biochemist wasn't comfortable with.
I can't imagine how bad concentrated extracts are.
I get the sentiment, but it's not quite that simple. For example, certain kinds of red yeast rice are banned for sale in the USA because they contain medically significant amounts of lovastatin.
And also some food is a drug :)
Pedantic, I know, but I think the parent's real point (pay attention to what you put in your body) is only strengthened by the fact that this line is blurry.
"Walking is man's best medicine." --also Hippocrates
There's a syllogism in there somewhere. Probably about soup made from worn-out shoes.
I should stop now, before someone starts thinking this might be a good idea.
The important point to grasp behind all this concern over "supplements" is that there's no such thing as a supplement. Everything that's not a food is a drug. If something is not part of a human diet somewhere - i.e. if it's been extracted and refined significantly - then it's a drug. (Does that mean you regulate supplements? No, because then you end up in ridiculous situations like banning high doses of water-soluble B vitamins. Banning certain brands and formulations is sometimes appropriate.)
Drugs have a dose-response curve, a median lethal dose, and all the rest. People taking "supplements" (taking them seriously, beyond taking a common-or-garden multivitamin you can pick up anywhere) should be aware of this and understand the risks.
"Natural" doesn't mean safe. Polio is natural.
Not all sets of genetics tolerate all "supplements" at recommended dosages.
In vitro is not in vivo.
Animal studies are not human studies.
I got into nutrition and supplementation through bodybuilding, and within that community the knowledge that things you put in your body can hurt you, do your homework is fairly widespread and well passed-on. Unfortunately that perspective hasn't really permeated broader fitness culture.
I think the attitude of "have this problem, take this pill" (without regard for risks or better options) is mostly at fault here. I'd argue corporate pharmaceutical companies have some culpability here - "ask your doctor if X is right for you" - or don't, and just bloody do some cardio or something.
This article is only interesting if you still conflate "green tea" with "natural" and "natural" with "safe".