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I talk a lot in this space about antifragility. For those who need a reminder it’s the idea that certain things get better/stronger in the presence of stress. For a really in-depth explanation see my post on The Ideas of Nassim Nicholas Taleb who discovered the idea. (In the same way that Columbus discovered America i.e. it is something which has always been there, but he brought attention to it and named it. And yes, I know that Columbus didn’t name America, but he did name the Indians.)

I am not the only person to discuss antifragility, and nearly any time someone does they bring up the hygiene hypothesis, because it’s such a great example of the principle in action. This includes me, but on previous occasions I didn’t go into it in much depth. I’m going to start this post by rectifying that.

The hygiene hypothesis, as originally formulated by David Strachan, speculated that a lower incidence of childhood infection translated into higher rates of hay fever and asthma. From the beginning Strachan noticed that family size was a factor as well, More brothers and sisters provided more avenues for childhood infection. But that still leaves the question of why a lack of childhood infections would map, later, to a greater incidence of hay fever and asthma?

Initially it was thought that it was mostly things like measles, the flu, and other childhood diseases that were the primary culprits, but then Graham Rook came along with the “old friends” theory. From Wikipedia:

Rook proposed the “old friends hypothesis” which some claim offers a more rational explanation for the link between microbial exposure and inflammatory disorders. He argues that the vital microbial exposures are not colds, influenza, measles and other common childhood infections which have evolved relatively recently over the last 10,000 years, but rather the microbes already present during mammalian and human evolution, that could persist in small hunter gatherer groups as microbiota, tolerated latent infections or carrier states. He proposes that humans have become so dependent on these “old friends” that their immune systems neither develop properly nor function properly without them.

Hay fever, asthma, and other allergies are products of overactive immune systems, and while the clinical details of the hypothesis would take us into the weeds of TH1 vs. TH2 cells and much more besides, I don’t think it’s over simplifying things too much to describe it this way: The immune system needs something to target, and in the absence of historically harmful agents, it ends up targeting non-harmful agents, like pollen and peanuts. In the case of peanuts this reaction can be so extreme that people with peanut allergies can die after ingesting them. To return to the principle of antifragility, the immune system is antifragile. It needs stress to develop appropriately. In the absence of sufficient stress it goes a little haywire. (Or maybe a lot haywire.) To quote from Rook, “Evolution turns the inevitable into a necessity.” In this case, harmful agents were historically inevitable, and in the end they became necessary.

I find it very interesting to review examples of what the immune system considers beneficial stress (at least according to the research):

  • Large families
  • Older siblings
  • Early daycare
  • Rural Living
  • Contact with animals
  • Poor sanitation
  • Parasitic worms
  • Absence of antibiotics
  • Non-western lifestyle

As you would expect this is a list of things mostly absent from modern life, and includes some things we’ve put a lot of time and money into banishing. It’s equally interesting to review examples of the kinds of conditions that can result from not getting enough of this stress (at least according to the research):

  • Type 1 diabetes
  • Multiple sclerosis
  • Some types of depression
  • Cancer
  • Autoimmune diseases
  • Hay fever
  • Eczema
  • Asthma
  • Autism
  • Food allergies

This is a pretty nasty list, and as I already pointed out, some of the items on the list can be fatal. And if you’ve been paying attention you’re aware that most have been increasing recently. The questions is how recently. Thus far I have intentionally avoided mentioning the year that Strachan first proposed the idea, or the year when Rook amended it. But from my perspective this is one of the things that makes the hypothesis so consequential. To take a step back for a second, one of the big questions I keep returning to is how different is the modern world from the world of 50 or 100 or a 1000 years ago? The hygiene hypothesis would seem to indicate that it’s very different and that the difference is recent. The first formal proposal of the  hypothesis, by Strachan wasn’t until 1989, the year I graduated from high school. (Yep, it’s my 30th year reunion this year. I think I’m going to skip it.) And Rook’s amendment, wasn’t until 2003, and it’s gotten much worse since then. For example, the WSJ reported a 377% increase in severe allergic reactions to food just in the decade between 2007 and 2017.

Depending on who you talk to the modern world started in the early 18th century with the invention of the steam engine and the Enlightenment. Or maybe it was the late 19th century with the harnessing of electricity. Or perhaps it was the end of World War II when conflict between the great powers ceased. Or if we’re looking more in the area we’re concerned about. Perhaps it was when Pasteur solidified the germ theory of disease in the 1860s or when Fleming discovered penicillin in 1928. But all of these things still happened a long time before 1989 to say nothing of 2003 or 2007. Why is it so bad now? I understand that people are not eager to go back to having tapeworms or cholera epidemics from poor sanitation, but as best I can tell the last cholera epidemic in the US was in 1911, which as you’ll recognize is significantly before 1989.

I’m not sure of the answer to this question, nor is it the intent of this post to seek that answer. It’s just one more alarming thing about the current state of the world. Also, while the hygiene hypothesis is exceptionally interesting all by itself, I’d like to see where that idea takes us if we’re willing to expand it a little bit. Because it’s not just the immune system which experienced inevitable stress historically, all aspects of our existence were subject to inevitable stress, and I’m wondering, if we start to view these other avenues of stress as necessary does it bring any insight?

I just finished listening to The Power of Vulnerability by Brené Brown. I picked it up because I started hearing her name everywhere all of the sudden. Which I’m sure is because I started looking for it rather than some dramatic increase in her popularity over the last month. But once my attention was drawn to her I was curious to see what she had to say. My initial take is that she’s very engaging and funny, full of charisma (the thing I listened to was her presenting a six part instructional course) and I can definitely see why people would be drawn to her. I’m also very interested in her take on the benefits of guilt, but still somewhat unclear how she draws a bright line between that and shame, which as far as I can tell is the worst thing in the world from her perspective. I’m certain that I should read more of her stuff before I make any further comments, also that’s not why I’m bringing her up. I bring her up because she said something that starting me thinking about this whole subject.

At the beginning of her presentation she tells the story of two families, brothers, each of which has a wife and a few kids. Unexpectedly there is a “very violent, traumatic event”, and one of the kids dies. Obviously all the parents, and the other kids are devastated by this. Over the course of the next few years each family sends one of their kids off to war. “One comes back, one doesn’t.” Then a year after that one of the brothers loses his house after the bank forecloses on it. She then goes on to say that the story is a metaphor for the nation as a whole. The first violent event was 9/11, which was followed by the wars in Afghanistan and Iraq. Which was then shortly followed by the financial crisis of 2007-2008. That we are those families. That it has been “trauma after trauma for us.”

Brown places a lot of focus on scarcity, vulnerability and shame. This story, in addition to being a story of repeated trauma, is a story of increasing scarcity, or at least the perception of scarcity. She says that she started her research in 2001 and she has “watched scarcity, absolutely shift over this time.”

This whole thing really struck me because as disasters go 9/11 was kind of small potatoes. In the end 2,996 people died. Not to take anything away from the tragedy of those deaths, or the impact it had on those families, but I could list a dozen other disasters that are 100x or even a thousand times as bad. To just take one example, in 1976 somewhere between 250,000 to 650,000 people died from an earthquake in China. That was not even that long ago. How many people have even heard of that earthquake? And is there any evidence of permanent scarring in China? Not that I can see.

Turning to Afghanistan and Iraq, there were 6,713 US deaths. Those are also tragic, and kind of senseless, and it’s ironic that that total is twice as much as the number of people killed in 9/11. But once again, as wars go neither Iraq or Afghanistan has been particularly bad. And if that scarred us, how much more did it scar the actual Iraqis, where the low estimate for violent deaths is 151,000 against much smaller populations. And that’s just stuff that’s happened recently. You don’t have to go that far back before you start to encounter things like the Siege of Leningrad, which lasted for years and ended up killing over a million people. In fact, if you want trauma after trauma, then you should look at the Russians from the 1st World War up through the fall of the Soviet Union (and probably beyond).

Finally as far as financial crises and scarcity go, 2007-2008 was severe, but very short. Nothing as close to as deep or as long as the Great Depression. Unemployment hit 10% once, in late 2009. During the Great Depression it was above 10% for 10 years, with a high above 20%! And whatever scarcity we’re experiencing it’s nothing compared to the scarcity which exists in most of the less developed world, to say nothing of the scarcity which existed for most of recorded history.

Despite all of this Brown does have a point. As she goes on to say:

We are…The most in debt, obese, addicted, and medicated adult cohort in history.

How is this possible? How is it that Brown and her audience can look back and see “trauma after trauma”? Why do things seem so awful and hopeless for so many despite the unparalleled abundance of modern life? When the actual chance of dying from any of the trauma’s she mentioned is almost infinitesimal. (Even for people in the military it’s still pretty low.) And yes the 2007-2008 financial crisis was pretty bad, but how many people literally starved to death because of it? How many homeless people died? How many of them died because of the crisis, who wouldn’t have otherwise? And how many of those are the kind of people who show up at a Brené Brown seminar or read a Brené Brown book?

You may have already guessed where I’m going with this, but what happens if we combine Brown’s observations with the hygiene hypothesis? If we start looking at beneficial stress beyond the realm of the immune system? If we start looking at all forms of stress? Is it possible that just as our immune system has started targeting benign agents in the absence of actual infections. That our psyche has started marshaling all of its defenses against anything negative no matter how slight, in the absence of true trauma? Reacting to things that would have been inconsequential historically by going into the equivalent of psychic anaphylactic shock?

I don’t know, I want to stress that this is just me speculating. Tossing an idea out there and seeing what it looks like when I’ve actually written it down. Also, a faithful reader of this blog, did just point out to me that science is not conducted by pointing out lots of things which confirm your hypothesis, it’s conducted by looking for things which falsify it. Though yet another reader pointed out that blogging has its own set of rules which are different than those of science. And if I were to say right now that this idea is obviously false because of X, it wouldn’t be a very interesting post. (Less so…) That said I am interested in any ideas for how this concept might be falsified. I guess if true trauma continues to decline without psychological issues getting worse, or if they actually started improving that would be one way. That certainly doesn’t seem to be the way things are going, but the trend could always reverse. So while I should and will pay attention to things which might falsify this idea, I am going to spend most of the rest of this post pointing out things which I feel lend support to this idea.

To start with there’s the subject of last week’s post. The hoax Jessie Smollett pullIs that possibly an example of this? It might be, but if it is, it appears that the immune system of the entire society over-reacting, not just the psychological defenses of a single individual. Though before we dismiss it there might still be an interesting parallel.

When I imagine the immune system I imagine white blood cells swarming a parasite (and I know that this is not one of the mechanisms involved in the hygiene hypothesis). It’s possible to imagine that shameful behavior is dealt with in a similar fashion by human society. A certain percentage of individuals are predisposed, by culture and genetics, towards recognizing and shaming certain behavior. Call them scolds. And maybe some other percentage are predisposed towards giving individuals, particularly allies, the benefit of the doubt. Call them advocates. In a setting where the average group size is 150, and the percentage is, say 2%, you have three scolds and three advocates. But now that social media has allowed the community to scale up to be the entire nation, you still have individuals doing dumb (or understandable) things, but rather than three scolds and three advocates, each individual now has thousands, if not millions of each. The body is nothing but white blood cells swarming some parasite.

Let’s turn to another possible example, this one at the individual level. The other day I was out to lunch with an old friend of mine and he mentioned that he was having financial troubles. He had been working as a chef, but finally the lack of opportunities for further advancement and the long hours were just too much and he had to quit amidst declining health. He got another job working at a big plumbing supply store, and he’s doing a lot better, but he’s not making as much money and his kids are in the expensive stage of life (i.e. teenagers). Both he and his wife agree that the obvious solution would be for her to start working, and his wife is willing, but she claims that her social anxiety prevents her from working most traditional jobs. She has made some attempts to find a job that would allow her to work from home, but has so far been unsuccessful. (I should mention at this point that I have altered details of this story to protect the identity of the wife.)

In the past there have been times and conditions where if you didn’t work you died, and people, presumably, never said during those times that they couldn’t work because of “social anxiety”. This leaves us with a few possibilities.

  1. Social anxiety is just an excuse, she doesn’t want to work for some other reason. She’s lazy, or she is secretly hoping her husband will divorce her, or something similar. This is certainly possible, but based on my conversation with her husband, and my slight acquaintance with her, I don’t think she’s “faking it”, but you never know.
  2. If she was really in danger of death or some other horrible consequence (e.g. homelessness) she would work, but absent that her anxiety is too powerful to overcome. If this is the case then it could be that social anxiety has always been present and it’s just the consequences of not working which have changed. That said, their situation is pretty dire, for example they will probably lose their house. (Though that shouldn’t make them homeless.)
  3. She really does have crippling social anxiety, and it wouldn’t matter how bad things are, there really is no way for her to overcome the pain caused by having to interact with lots of strangers in a professional capacity. It is literally incapacitating.

I’m not sure which it is, but I suspect it’s two or three, both of which present problems. Also, if this were the only person who claimed to be unable to do necessary and important things because of psychological issues then it wouldn’t be worth mentioning, but there are millions of people who receive disability benefits because of mental issues which render them incapable of working, and this number doesn’t even include people like my friend’s wife. Once again we have the same core issue. Under the hygiene hypothesis we reduced the number of harmful antigens, but that made some people less physically healthy rather than more. In this example we have reduced the amount of harmful trauma, but this has made some people less mentally healthy rather than more. To repeat Brown’s point:

We are…The most in debt, obese, addicted, and medicated adult cohort in history.

The best example of all for this idea comes from the book Tribe, by Sebastian Junger. Which I discussed in a previous post. Speaking about the reaction of Londoners during the Blitz he said:

On and on the horror [of the Blitz] went, people dying in their homes or neighborhoods while doing the most mundane things. Not only did these experiences fail to produce mass hysteria, they didn’t even trigger much individual psychosis. Before the war, projections for psychiatric breakdown ran as high as four million people, but as the Blitz progressed, psychiatric hospitals around the country saw admissions go down…Psychiatrists watched in puzzlement as long-standing patients saw their symptoms subside during the period of intense air raids.

He then goes on to talk about the positive effects of war on mental health in general, including decreases in depression, suicide and even frequency of epileptic seizures. What might be considered an environment of poor mental hygiene produced improved mental health.

Interestingly enough, my dad recently read Tribe, and his conclusion was that despite being a very interesting book, that it wasn’t exactly scientific. I agree, and most of what I’ve written here hasn’t been especially scientific either, but I think there is something to this. That the negative second order effects of removing historical stress is an area which needs a lot more study. There is some stuff out there, for example a study claiming that growing up in an urban environment without pets increases vulnerability to mental illness. But so far whenever I hear people talk about the increased rate of modern mental illness as Brown does, their solution is always to reduce stress. In Brown’s case it’s to reduce the stress of shame (and maybe replace it with the positive stress of guilt? I’m not sure, but in any case more guilt is definitely not her focus.) Which is not to say it’s easy to identify and introduce positive stress. People with severe allergies have been known to infect themselves with hookworms. (Which worked by the way.) I’m not sure what the mental health equivalent of that is.

Whatever your feelings on the above. Humans are antifragile. We have survived thousands if not millions of years in environments of extreme stress and trauma, and yet now, it’s clear that less and less objective trauma is producing greater and greater reactions. And at some point we’re going to need to figure out why that is.


I’m taking next week off because I’ll be at Gary Con. But feel free to check out previous posts, for example the post I did on Tribe. And while you’re looking over the vastness of my writing, consider donating.