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Comment by mfer | Hacker News Reader

Except, it misses the point and doesn't really do that while being persuasive.

According to the Blue Zone researchers, some of the Blue Zones are disappearing because the generations that came after the oldest live differently and much shorter. By differently, their eating, body movement, and other characteristics are different. Looking at the whole population doesn't segment for differences between generation. So, nuance is lost.

In some areas, like the Blue Zone in the US other research is finding the people who live there are healthier than the surrounding populations. Then you have to ask, what area do you average over for your measurement and statistics?

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> According to the Blue Zone researchers, some of the Blue Zones are disappearing because the generations that came after the oldest live differently and much shorter.

Of course they would say that. But if these zones are simultaneously recording births better and reducing welfare fraud, and if 80%+ of the centenarians either had no birth certificate or were actually dead, I'm going to need more than "but they're also changing lifestyles" as an explanation.

We're talking here about unusually long life, not just "he's still going strong at 85" long. No one here is arguing that people who are active and eat right don't have a longer healthspan, but that's a concept that's provable without the so-called Blue Zones.

I listened to an interview with the author during the week, in short as soon as you start getting reliable recording of births and clamp down on old age welfare fraud the phenomenon disappears.

"Then you have to ask, what area do you average over for your measurement and statistics?"

This is a big thing that I didn't seen in the paper this article is based on. It seemed like the author was comparing adjusted numbers from the blue zone with unadjusted numbers from non-blue zones. Without comprehensive investigation of error rates and even different error mechanisms by locale, it seems like a poor comparison to make. Comparing life expectancies is better than comparing outlier centarian numbers, but you are right that it depends on what other areas we are using as the baseline or average (and I take it a step farther by saying it depends on what error adjustments need to be made to both data sets).

The whole blue zone idea is a bit misapplied though. These population studies find new variables to look at. Then you have targeted studies to investigate thos variables. Discrediting the centarian numbers doesn't discredit the findings on stuff like a mederteranian diet having better health outcomes than the standard western diet, etc.

Kinda depends on how much you value inductive vs. deductive reasoning, but the authors make the deductive case that:

- There's strong incentives to misreport in these areas (the compelling example from Sardinia was that the person is alive for the purposes of pension fraud, but really dead)

- People who are incentivized to report people being older than they are will do so

And the inductive case relies on data, which is presumed to be totally flawed because of the misaligned incentives.

It is very much to the point, addressing the specific claims and methodology of a specific (and apparently somewhat influential) study.

You are, of course, free to speculate that there are other issues related to longevity than those considered in the study in question, but even if these suppositions are correct, in no way would this justify saying the paper being discussed here misses the point. The point is that the blue zones study is too flawed to support any definite position, which includes both its own conclusions and the more nuanced issues about which you speculate.

> It is very much to the point, addressing the specific claims and methodology of a specific (and apparently somewhat influential) study.

Except, the author doesn't discredit specific claims of the Blue Zones. For example, the Blue Zones might take an area and state there is a higher rate of centurions who are healthy and capable. The counter to that might be the average life span in the region isn't an outlier. In one case you're looking at a targeted subgroup and the other your looking at the population as a whole. One observations doesn't disprove another.

This is just one example. It's why I call the work misleading.

You are using "might" more than once here. I have my opinions too, and FWIW, this looks like motivated reasoning, holding the response to a much higher standard of proof than the original claim.

Or now better records are kept the incorrect data dies off

There was a study I read about in Barrons that was noting that places a western diet goes the health care costs then start going up. Other studies have found that a western diet leads to more unhealthy outcomes (increased disease and earlier death).

I state this to point out that there are other variables at plan than just changes in record keeping.

Healthcare spending goes up. As you’d expect from a country starting to become richer.

Also, please show reliable studies that show that western diets lead to more unhealthy outcomes.

Compared to what, third world diets with their insufficient nutrition and starvation?!

Furthermore food studies are notoriously badly done.

I think the more likely causation here is that higher incomes drive increase in western diets, and higher incomes lead to higher healthcare spending.

Could there be third correlated variable namely income that correlate with both western diet and health care costs? Or even better records of disease and deaths?

> the generations that came after the oldest live differently and much shorter.

This presupposes that the previous generation was in fact living longer, which the linked study showed is not the case at all.

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