The fasting analogy is interesting, as is the analogy with exercise—some kinds of activities are beneficial in the long-run even when they are damaging/unpleasant in the short run. But surely these are exceptions to the general rule, right?
Besides exercise, it’s not good to repeatedly injure yourself and then have the wounds heal. (Exercise is essentially the small, specific subtype of “injury” which is actually good for the body in the long term.)
Getting sick with a cold or flu is good at building immunity to that kind of virus when it comes around a second time, but aside from immunity concerns, it would be better for your health to never become sick at all. (As with viruses, the same goes for diseases caused by parasites or bacteria.) Especially as a young child, getting badly sick can impact your development and later IQ / income / etc substantially. Getting mildly sick is probably mildly bad for those same metrics.
One of the reasons junk food is bad is because it has lots of quickly-absorbed sugars, which rush into your bloodstream and force your insulin/glycogen system to ramp up quickly and do a lot of work. Over the long term, putting all this stress on your body’s ability to absorb sugars is though to reduce your body’s insulin sensitivity, leading to metabolic disorders like prediabetes. So, chronic consumption of junk food is bad—but should I prefer a totally healthy “low-glycemic index” diet? Or a mostly low-glycemic index diet but I occasionally consume a blast of sugary sweets to “exercise” my insulin system? I don’t think science has given us a real answer here, but most doctors would probably recoil in horror at the idea of “exercising” one’s metabolic system by occasionally binging junk food, and I’d be inclined to agree with them.
Some kinds of psychological stress and trauma are probably beneficial in the long run (for instance, working hard on a project to meet a deadline and feeling invigorated + learning better productivity skills as a result), while other kinds are probably just bad.
Basically, it seems like there are plenty of examples on both sides, and I can’t figure out any general rule that would let me predict ahead of time which seemingly-bad behaviors/stressors are secretly good or not. The examples of exercise and fasting are helpful reminders to keep an open mind, but I don’t think they can tell us much more than that when we’re trying to figure out how to think about sleep.
(Similarly, some things about the modern world are “superstimulus”—like junk food. But others are just progress—like the fact that I can afford a healthy diet with lots of meat and vegetables if I so choose, while my agrarian ancestors got much more of their calories from samey, not-very-nutritious grains. I don’t know if comfortable beds are a superstimulus encouraging us to oversleep harmfully or just modern progress enabling us to higher-quality sleep. But I do appreciate that the “superstimulus” hypothesis is reasonable and encourages us to keep an open mind.)
I am much more sold on “variety is good for humans, and mild-moderate deprivation and excess is variety” than “humans should permanently run on much less sleep than they think they need” or “sleepiness is a lie”.
One tricky thing here is humans aren’t actually guaranteed to have a pareto optimim, or to have a path that gets all good things. It seems really plausible childhood illnesses damages development and IQ, and lack of childhood illness causes allergies and immune vulnerability later (I think think the hygiene/old friends hypothesis is largely correct, even if it doesn’t support eating dirt in particular), and there isn’t an ideal level that gets you your max IQ and no allergies. Variety is something of a hack to get some of both and also create a discovery process for what you need more at a particular moment.
Most doctors would probably recoil in horror at the idea of “exercising” one’s metabolic system by occasionally binging junk food, and I’d be inclined to agree with them.
In the US, pregnant women get a glucose tolerance test to check for gestational diabetes, which involves drinking 100g of glucose on an empty stomach and seeing how quickly it gets processed. But that’s once or twice per pregnancy.
The fasting analogy is interesting, as is the analogy with exercise—some kinds of activities are beneficial in the long-run even when they are damaging/unpleasant in the short run. But surely these are exceptions to the general rule, right?
Besides exercise, it’s not good to repeatedly injure yourself and then have the wounds heal. (Exercise is essentially the small, specific subtype of “injury” which is actually good for the body in the long term.)
Getting sick with a cold or flu is good at building immunity to that kind of virus when it comes around a second time, but aside from immunity concerns, it would be better for your health to never become sick at all. (As with viruses, the same goes for diseases caused by parasites or bacteria.) Especially as a young child, getting badly sick can impact your development and later IQ / income / etc substantially. Getting mildly sick is probably mildly bad for those same metrics.
On the other hand, I enjoyed your post a few months ago examining whether letting kids play outside and get dirty is helpful for calibrating their immune systems and reducing allergies later in life. It seems like the “hygiene hypothesis” is less firmly established than I thought, but if true it would be an example something else like exercise and fasting where injury/stress leads to long-term benefit.
One of the reasons junk food is bad is because it has lots of quickly-absorbed sugars, which rush into your bloodstream and force your insulin/glycogen system to ramp up quickly and do a lot of work. Over the long term, putting all this stress on your body’s ability to absorb sugars is though to reduce your body’s insulin sensitivity, leading to metabolic disorders like prediabetes. So, chronic consumption of junk food is bad—but should I prefer a totally healthy “low-glycemic index” diet? Or a mostly low-glycemic index diet but I occasionally consume a blast of sugary sweets to “exercise” my insulin system? I don’t think science has given us a real answer here, but most doctors would probably recoil in horror at the idea of “exercising” one’s metabolic system by occasionally binging junk food, and I’d be inclined to agree with them.
Some kinds of psychological stress and trauma are probably beneficial in the long run (for instance, working hard on a project to meet a deadline and feeling invigorated + learning better productivity skills as a result), while other kinds are probably just bad.
Basically, it seems like there are plenty of examples on both sides, and I can’t figure out any general rule that would let me predict ahead of time which seemingly-bad behaviors/stressors are secretly good or not. The examples of exercise and fasting are helpful reminders to keep an open mind, but I don’t think they can tell us much more than that when we’re trying to figure out how to think about sleep.
(Similarly, some things about the modern world are “superstimulus”—like junk food. But others are just progress—like the fact that I can afford a healthy diet with lots of meat and vegetables if I so choose, while my agrarian ancestors got much more of their calories from samey, not-very-nutritious grains. I don’t know if comfortable beds are a superstimulus encouraging us to oversleep harmfully or just modern progress enabling us to higher-quality sleep. But I do appreciate that the “superstimulus” hypothesis is reasonable and encourages us to keep an open mind.)
I am much more sold on “variety is good for humans, and mild-moderate deprivation and excess is variety” than “humans should permanently run on much less sleep than they think they need” or “sleepiness is a lie”.
One tricky thing here is humans aren’t actually guaranteed to have a pareto optimim, or to have a path that gets all good things. It seems really plausible childhood illnesses damages development and IQ, and lack of childhood illness causes allergies and immune vulnerability later (I think think the hygiene/old friends hypothesis is largely correct, even if it doesn’t support eating dirt in particular), and there isn’t an ideal level that gets you your max IQ and no allergies. Variety is something of a hack to get some of both and also create a discovery process for what you need more at a particular moment.
In the US, pregnant women get a glucose tolerance test to check for gestational diabetes, which involves drinking 100g of glucose on an empty stomach and seeing how quickly it gets processed. But that’s once or twice per pregnancy.