The legacy of the Y2K bug tells a story about prevention at large scale, but the Preparedness Paradox applies to individuals as well. There is no shortage of advice out there for how to live a long and healthy life. It comes at us from all directions. Governmental agencies and self-help podcasters preach their ideas of what you can do to live forever.
And yet, some people who do everything right still die early, be it from freak accidents or fateful disease. Some people do everything wrong and live to see 100. How can we know whether preventative medicine will be worth it in the end?
Longevity Guru Peter Attia wrote a whole book based on the idea that mimicking the internal homeostatic mechanisms of centenarians can unlock universal longevity. But Attia admits very early in his mammoth how-to-book/memoir mashup Outlive that he’ll never be able to prove that his ideas actually achieve his goals. Because of the timescales involved, the multifactorial inputs required, and the complete lack of understanding of mechanism, there can be no randomized trial of his longevity protocols. You can’t do “evidence-based” medicine to live forever. Instead, Attia unironically calls his approach “evidence-informed” medicine. Evidence-informed means he reads a lot of papers, talks to people on his podcast, and comes up with what he currently thinks is best based on these experiences. This rings hollow. Given the vastness of the scientific literature and the confirmation bias provided by talking to his friends, “evidence-informed” is just an arrogant, nerdy euphemism for “I go with my gut.”
Indeed, the evidence-based medicine crowd is diametrically opposed to Attia. Evidence-based medicine preaches a medical conservatism that is loath to treat healthy people as patients and argues for only employing interventions that have been demonstrated effective by randomized clinical trials. One of the pioneers of the evidence-based medicine movement, David Sackett, wrote an impassioned editorial decrying “The arrogance of preventive medicine” in the Canadian Medical Association Journal in 2002. He vents:
“First, it is aggressively assertive, pursuing symptomless individuals and telling them what they must do to remain healthy… Second, preventive medicine is presumptuous, confident that the interventions it espouses will, on average, do more good than harm to those who accept and adhere to them. Finally, preventive medicine is overbearing, attacking those who question the value of its recommendations.”
Like in the case of the Y2K story, Attia and Sackett are correct at the same time. How we balance their perspectives and make sense of our lives is what’s challenging.
What makes Sackett more right than Attia is his honesty and humility about what is out of our control. Our bodies, which work so hard to maintain homeostasis, can only do so for so long. And if we spend all of our time preventing the worst, even Attia admits that this makes life stressful and miserable.
A beautiful meditation on how homeostasis can hold for only so long is Siddhartha Mukherjee’s essay “My Father’s Body, at Rest and in Motion.” Mukherjee mourns the death of his father, describing the efforts required to keep him in order until everything falls apart. In a poignant scene, Mukherjee describes how his mother and his father’s nurse worked to create a simulation of his father’s old life in hopes that it might remind his bodily systems of how they used to interoperate:
“And then, quietly, a new kind of physiology started to coalesce around him. The fruit and vegetable sellers began to turn up at home. The daytime nurse—a scraggly young man nicknamed Bishnu: the god, among other things, of maintenance and preservation—made a habit of propping him up in his rocking chair on the balcony every morning, and having the various venders congregate below like a worshipful throng. My father was delighted to be back among the believers. He would banter with them from above—a king under house arrest, but a king nonetheless—berating them about their prices; protesting the abysmal quality of the eggplants; asking why he, at his age, must suffer the sins of their bruised cauliflowers; and why the fish was never quite fresh. It was a small miracle: Mr. Mukherjee could no longer go to the market, and so the market came to Mr. Mukherjee.
“In retrospect, I understood that this, too, was homeostasis of a sort. The little rituals saved him.”
Trying to keep elements of his daily routine together was a way to sustain his life. This simulation wasn’t necessarily what we would call medical intervention. It was an attempt to experiential maintain constancy to maintain physiological constancy.
Mukherjee sees homeostasis in everything, from his father’s body to India’s infrastructure. Homeostasis is about regulation and control, and one of the ways we aim to prolong life is by externally maintaining homeostasis to help our internal homeostatic mechanisms. He raises an interesting question about preventative medicine.
In the tale of the Y2K bug, there were competing alternatives: the expensive fix-everything approach and the fix-on-failure alternative. Some mix was probably required to mitigate the effect of the problem. The same is true with ourselves. No matter how complicated the modern evidence-informed scientist life gurus make it out to be, some measures of prevention are likely helpful. If you look past Attia’s kookier, more expensive advice like getting full-body cancer scans or taking rapamycin prophylactically, then Outlive’s prescriptions amount to eating well, exercising, sleeping well, and living a low-stress lifestyle. Sounds good to me!
But how can you know your measures of prevention did the right thing? Did your daily jogging and healthy diet get you to a healthy 9th decade? Was everything you did to sustain your life worth it because of how you were able to live it? Will you run a statistical regression to prove you lived your life to the fullest?
one of my very favourite papers to use as an example of the perils of being too "evidence based" is a recent one which takes a bit of a look at the "blue zone" clusters of supercentenarians and concludes (this is my interpretation rather than their actual conclusion) that the true secret of long life is to be born in a place with poor birth certificates issuance policies and retire living with family members in a place with a high rate of pension fraud.
Have really appreciated your recent articles on medicine.
Have you come across Sterling's model of allostasis (https://folk.uib.no/nfijg/biopages/theme2basalmon/papers/Sterling2012.pdf) as a complement to homeostasis?
The basic argument is that our organs (and biological systems in general) anticipate needs in addition to reacting to errors.
E.g. even though blood pressure seems homeostatic in isolation, our blood pressure to certain muscles rise before there has been any error signal to react to.
Curious how you might think about this as a control theorist.