The Blue Zones researchers answered. Here is what the reply settles, and what it can't.

Fifteen months ago we wrote about the Ig Nobel Prize awarded to a demographer whose work argues that many of the world's claimed oldest people are the product of missing birth certificates and pension fraud, and that the Blue Zones might be artifacts of bad records. In the December issue of The Gerontologist, the gerontologists Steven Austad and Gianni Pes reply. Their argument is specific: the four original longevity regions — in Sardinia, Okinawa, Ikaria and Nicoya — were identified only after ages were validated against civil, church, genealogical, military and electoral records, and places where records could not be validated were excluded. They also concede something important: a zone is not permanent. Okinawa's advantage has faded as its diet and habits have changed. Pes co-discovered the Sardinian zone, which is an interest readers should weigh and which the authors do not hide.

What the reply settles. The strong version of the critique — that the Blue Zones are simply fraud and clerical error — does not survive this paper. Four regions with independently validated ages had, at a point in time, unusual concentrations of very old people. The weak version of the critique is untouched, because it was never about these four regions: the demographer's data concern supercentenarian records in large countries, and the commercial Blue Zones brand has long since expanded beyond the four validated regions to places and products the paper does not defend. What the paper also cannot settle is cause. Validated ages tell you that people in a place lived long. They do not tell you which of their habits did it, and the popular account — the beans, the walking, the neighbors — remains a plausible description, not a demonstrated mechanism.

Loree’s take

I use the Blue Zones in my office as a picture, not a prescription: communities where movement was built into the day, food was mostly plants cooked at home, old people were needed and nobody ate alone. The paper leaves that picture intact and reminds me that it was a snapshot. Okinawa is the lesson. The habits protected people until the habits changed. Nothing about the place was magic.

Ben’s take

Notice the distance between the science and the brand. The scientists defended four regions with records and admitted one is fading. The brand sells certified cities, cookbooks, meal kits and a lifestyle under the same name, none of which this paper validates and none of which it mentions. When a critique lands on a brand, the brand points to the science. When the science is defended, the brand takes the credit. Keep them separate; the paper does.

Why it matters to a recovering optimizer. The Blue Zones were never evidence that a protocol works. At their best they are evidence that ordinary life, arranged a certain way, is enough — which is the thesis of this site. Today's paper makes that case more carefully than its critics or its marketers have, and it leaves you with the right question for any longevity claim: validated how, in whom, and does it still hold?