Many people here in the US are very concerned about health. Given the insansity of the US healthcare system and the extreme poverty that can result from illness if you don't have decent health insurance, I guess this is sort of understandable. But I get the feeling that there are a lot of "worried well" - those who obsess about having the right health supplements, eating the right food out of a poor understand of evolution / biology, spending some time detoxing (as Ben Goldacre says, no-one ever says what these "toxins" actually are), not getting their baby vaccinated, only drinking bottled water filtered thorough the kidneys of virgin yaks or buying expensive versions of everyday products because of some purported health benefit.
As a scientist, I get very pissed off when people use a corruption of science to try and lull people into believing something daft (hence my hatred of the paleo diet), or to fraudulently sell some useless product. Ben Goldacre's Bad Science should be required reading for everyone. Things to watch out for are overly jargonistic, sciencey-sounding words. If you read the word "quantum" in an advert trying to sell you something, chances are they're talking shite. Unless, of course, you're buying a Quantum Computer from D-Wave, but I doubt many of us have several million bucks to buy one of them. New Scientist has a good column that points out some of the more ridiculous quackeries.
I do CrossFit to keep fit and one thing that many CrossFitters rave about is butter coffee (blending butter into your coffee in the morning). It seems kind of deviant and weird to me, but this blog post isn't about that. It's about the website of the guy who made this whole butter coffee thing popular in the first place: yes, I'm talking about BulletProof Coffee. Before I go any further into this website of quackery, I'm going to have a read of the rules governing libel in a blog. Because the US is a very litigious place.
Okay, I think as long as I stick to quoting claims from the company's website and explaining why they're bollocks, I should be okay.
One of the big claims of this Bulletproof fella is that normal coffee is loaded with mycotoxins, toxins from fungal spores that grow if the beans are not dried properly. I'm trying to find the original page I read months ago that had links to lots of academic studies (many of the links were broken, misintepreted or linked to studies on completely unrelated things) but it seems to have been updated. Oh wait, I found it. Before going through some of this guy's claims, it's worth pointing out that he sells VERY expensive coffee, allegedly free of these toxins.
His very first claim about the evils of mycotoxins is that they cause cardiomyopathy, and he links to this article. The article explains why adriamycin does indeed cause cardiomyopathy. What is this adriamycin? An evil mycotoxin? No, it's an anticancer drug. Feel your charlatanometer starting to ring yet? It gets better. He next says that mycotoxins can cause hypertension and kidney disease, citing this evidence. And if one actually checks out the paper? It's describing potential side effects of using cyclosporine, an immuosuppressant, during heart transplant surgery. Do you see a trend here? Using sciencey-sounding words and citing scientific papers, whilst aesthetically pleasing, is only helpful if they are related to your argument.
In the interests of fairness, it should be pointed out that there is a wealth of academic literature demonstrating that various mycotoxins can do bad things to you. They are generally created when fungi colonise improperly stored food, and they do bioaccumulate so that trace amounts can be found in blood samples from most healthy people (data in the same article). A good place to learn about mycotoxins is this website from the UK food standards agency.
Are mycotoxins from coffee a risk? One study carried out in 1980 found that the levels detected were too low to warrant further study, and that even when they added the toxins to green coffee beans, most of it (70 - 80%) was destroyed by roasting. Mr Bulletproof coffee snake-oil merchant cites this study as evidence of mycotoxin presence in coffee. The study looks at 60 samples taken from green (unroasted) beans all taken from Brazil. One third of these samples did indeed have OTA (one of the toxins) present at an average of 2.38 µg per kilogram (that's 2.38 millionths of a gram per kilogram of green coffee bean). The most heavily contaminated sample was 7.3µg / kg, which is still below the European Union safety limit. The toxin is there, so that's bad, right?
Let's think about it. I'll be kind (for the sake of argument) and ignore the fact that these samples were all taken from one country, and that the majority of them had no toxin at all. Let's take the highest level of toxin, 7.3µg/kg. As we discussed, roasting the bean will destroy al least 70% of the mycotoxin, taking us to 2.2µg/kg. But coffee beans lose on average 16% of their mass during roasting, so our hypothetical STRONGLY contaminated coffee contains 1.85µg of mycotoxin per kg of coffee. Brewing one cup of espresso uses 7 to 9g of coffee beans so, assuming every last molecule of mycotoxin from our hypothetical contaminated beans gets into your cup, there will be 16.6ng (nanograms, or billionths of a gram) of toxin in your coffee.
The average minimum dose of OTA that I saw causing any biological effects in the literature was around 1 mg (1 thousandth of a gram) per kilogram of body weight (trust me here, I can't be bothered searching the literature again). Taking the (scrawny) textbook man weighing 70kg, he would need to drink 4,216,867 cups of espresso (at one sitting) made from the beans where I've greatly exaggerated the risk, to see significant biological effects from the mycotoxin. Given that the lethal dose of caffeine needed to kill 50% of rats is 192mg/kg body weight, our textbook man would only be able to drink maybe 100 cups of espresso before he died. Let's be kind and say 200 because he has a caffeine addiction. I'm hoping that it's blindly obvious that you are at way more risk from the caffeine in your coffee than from potential mycotoxin contamination. Mycotoxins are a risk to health, but you're not going to get them from your coffee.
So, Bulletproof coffee man is selling snake oil. Literally. For just under $30 a pop, you can buy his special oil to add to your coffee. Its benefits include "Healthy Cell Walls" which sounds awesome. Except that you don't actually have cell walls. Unless you're a plant.
Although I've focused on someone selling coffee (he seems to make a lot of money from it), the general take-home message is the same for many things supposedly "bad for you". Yes, in sufficient doses, many things can be bad: pesticides, flame retardant chemicals, fungal toxins, vitamins, caffeine, fatty acids. Hell, any food rich in potassium gives you a measurable dose of radioactivity (measured using the banana equivalent dose). The point is that it's the level of exposure to these things that dictates the risk, not the presence. For example, check out one of the many websites that keeps track of things that the Daily Mail says can cause or prevent cancer (some things are on both lists!) I find it ironic that the people I meet who are most worried about ill effects from bad diets, coffee toxins, etc, are those who lead healthy, active lives so are least at risk from these supposed evils.
I have two take-home messages from my rant. One: beware people using sciencey-sounding things to push their bollocks onto you. Two: assuming you don't live in an arsenic mine or on the site of Chernobyl reactor 4, if you exercise and eat real food (made from vegetables and stuff), you'll probably be fine. There are better things to worry about.
