A pretty girl named Vani Hari runs a blog on the subject of healthy eating, organic foods, and the like on the aptly-named Foodbabe blog, and she's apparently built quite the following as measured by the number of her Facebook posts that are shared into my newsfeed. She has a great PR sense, and though I note that her "Professional Bio" doesn't list anything about background, training, or qualifications, it does include lots of pictures of her with celebrities.
It's gotten lots of attention, but, sadly, this is the kind thing that contributes to people becoming stupid.
I had never heard of azodicarbonamide before yesterday, and I don't know if it's harmful, helpful, or benign. As far as I know, I have no vested interest in any company that makes this chemical, nor do I in Subway except as an occasional customer.
But I know how to think critically; let's look at this campaign in that light.
And this isn't about her, it's about her claims.
This is a relatively small molecule that's mainly used in industrial production of plastics as an expanding agent, but also — in very small amounts — as an additive to flour as an "improving agent", which I believe helps the bread rise more quickly and whitens the appearance of the bread (a "bleaching agent"). It appears that the chemical process in both uses is similar.
I can imagine why Subway, who bakes bread right in front of us, might want to move the baking process along, but I'm neither a baker nor a food scientist so cannot vouch for this being the actual reason for it.
I understand that azodicarbonamide has been used for decades (which is neither evidence of harm or of safety).
Let's look at the claims by this campaign to see if they stand up as evidence, or just hyperbole.
Azodicarbonamide is the same chemical used to make yoga mats and shoe rubber.
Where do we start?
First, this claim suggests that azodicarbonamide is the primary ingredient (or at least a main ingredient) of yoga mats and shoe rubber, much like "flour is used to make bread". This is not just about the words, because the image of sandwich ingredients rolled up in a yoga mat reinforces the notion that you're eating bread made with ground-up rubbery stuff. Who'd want to eat that? Yuck.
It's disingenuous to suggest something is a main ingredient when it's really such a minor part (as if I said "bread is made from salt"). In fact, every one of Subway's breads has more salt than azodicarbonamide.
But more generally, the fact that a food additive is also used in some non-food context — usually a yucky one — provides no evidence of harm except due to ignorant hype.
Consider that the life-saving medication Coumadin is also used as rat poison.
It's banned all over the globe because it's linked to respiratory issues, allergies and asthma.
It's true that it's banned in much of the rest of the world, and this does give pause to a thoughtful person, but we have to dig in a bit here.
The magic word "linked" is commonly used to smuggle in all kinds of warrantless claims, and in this case, the "linkage" to respiratory issues is due to the inhalation risk of the raw material (as in: working in a factory that uses or makes the stuff), not consumption of trace amounts in food.
Everything I can find about Europe's ban relates to occupational exposure in the factory, with very little about routine consumption in food. There are many things that are harmful in pure inhaled form that nevertheless form a welcome part of our diet (example: try inhaling pure capsaicin powder, the "hot" in peppers, and see how it goes).
People have been killed in grain elevator explosions (the dust hazard) but it doesn't mean we're in danger by eating bread.
Though occupational exposure may well be problematic as suggested, the claims are completely bogus in the context of food exposure; this is shameful.
When a truck carrying azodicarbonamide overturned on a Chicago highway in 2001, it prompted city officials to issue the highest hazardous materials alert and evacuate people within a half mile radius! Many of the people on the scene complained of burning eyes and skin irritation as a result.
Again, this is about inhalation of the pure, raw material, and it's completely disingenuous to warrant that this makes a claim about harm from consumption of trace amounts in food.
A theme we will return to later is that the dose is everything: something by the tankerload may well be harmful, but lovely and beneficial in much smaller quantities.
When azodicarbonamide is heated, there are studies that show it is linked to tumor development and cancer.
There's that word "linked" again.
As noted before, azodicarbonamide is also used in plastics, and (in particular) to make gaskets for glass food jar lids to seal in the good stuff and keep out the bad stuff. There are concerns that one of the breakdown products is SEM (semicarbazide) can leach into the food in trace amounts during the sterilization process due to the high heat involved.
There is concern, especially for baby food jars, that SEM might be harmful, and I believe this is one of the main reasons why azodicarbonamide was banned in Europe for use in blown plastics. It appears from my research that this is more precautionary than a response to any specific evidence of harm.
When rats are fed high doses of SEM over a long time, it has been shown to cause some kinds of cancer, but these doses are so high as to be meaningless when applied to food consumption of trace amounts.
The US Food and Drug Administration permits the use of azodicarbonamide up to 45 parts per million (0.0045%) in flour, and even this vanishingly small amount is dramatically higher than the possible quantities of SEM that might result from breakdown products.
"Solo dosis facit venenum"
This translates from Latin to "The dose makes the poison", and this central maxim of toxicology came from Paracelsus in the fifteenth century; it's hard to overemphasize how important this is to keep in mind when considering food safety.
There's a widespread notion around "scary chemicals" that if a big dose is obviously harmful, then a small dose is at least a little harmful and should be avoided as a precaution. This is known as the linear no-threshold (LNT) model, and though it's often true (maybe arsenic or VX gas), it's not universally true.
Counter to the linear no-threshold model is the notion of "hormesis", which states that some things have positive effects in low (perhaps very low) amounts but turn harmful as the dose goes up.
Everybody knows the effect of hormesis even without knowing the name:
- Many vitamins are necessary for life but get harmful quickly as the dose rises (check out "niacin toxicity" for examples).
- There have been numerous studies on the health benefits of moderate amounts of red wine (not to mention the life-enriching benefits), but everybody knows what happens as the dose gets higher.
- You should always hydrate while engaging in exercise like long-distance running, but consuming too much water can lead to life-threatening hyponatremia due to the electrolyte imbalances produced.
Though some may advocate eliminating alcohol (not me!), nobody ever suggests that because there's some risk of harm with an outsized dose, we should not take vitamins or hydrate when exercising. The point is to use your head.
I have no evidence (or even a suggestion) that azodicarbonamide has a hormetic effect, so in that sense it's almost certainly not a nutrient necessary for life, but I've read widely that there are no studies that have shown harm of this chemical in humans.
I don't have enough information to know that the chemical in question is harmful, but I have more than enough to know a terrible argument when I see it.
I am not defending azodicarbonamide; I'm defending critical thinking
Here, as in most matters, I welcome evidence, not histrionics, in order to make a better decision about what I put in my body.
This campaign doesn't add evidence, only hype and fear, in nothing but a naked appeal to ignorance and emotion. Claims primarily based on big scary words, "linkages", and an utter disregard for orders of magnitude differences in dose ought not play a part in this kind of discussion.
Thoughtful people will ask more questions, study the literature, and rely on good arguments, not this nonsense produced with very savvy PR. Those who signed this petition based solely on the information presented by this campaign were not using their heads.
I wonder how long it takes before somebody claims that I'm on Monsanto's payroll?
Update: 1:55PM - It seems Subway has announced that they are removing this chemical from their products; they claim this has been in the works for some time, but I foresee an insufferable taking-of-credit in our future.
Update Feb 6 - I've been called to task for the title of this blog post, saying it's sexist and distracts from the content. Of course, everybody gets to decide how they react to anything, but when she calls herself Foodbabe, includes bikini pictures on her site, and generally gives off the pretty-girl vibe, nobody can be shocked, simply shocked to find that somebody else noticed.