In a word, fraud. That is, lying about your age. Supercentenarians and the oldest-old are concentrated into regions with no birth certificates and short lifespans. (That’s a preview version, not peer-reviewed.)
The introduction of state-wide birth certification coincides with a sharp reduction in the number of supercentenarians. In total, 82% of supercentenarian records from the USA (N=536) predate state-wide birth certification. Forty-two states achieved complete birth certificate coverage during the survey period. When these states transition to state-wide birth registration, the number of supercentenarians falls by 80% per year (Fig 1a), or approximately 69% per capita (Fig 1b).
The sound of settled science.
If no birth certificate was issued when you were born, then minus a notation in the family bible (or whatever) you are as old as you say you are. And there’s less status to being 91 than to being 101. And that doesn’t even count things like pension fraud. Is it better to be 62, or 68 if being 68 (on paper anyway) means you can collect your pension this year instead of in 3 years?
Hat tip to SiGraybeard with. The Secret of the People Living Past 100, who notes…
Sorry, but this literally made me laugh out loud. They’re not measuring longevity, they’re measuring fraud. This is the quality of science we get out the medical junk science world. This is what diet advice is being based on.
People study these populations and make pronouncements about diet and culture. The Mediterranean diet was popularized because apparently of a bunch of long-life effects. But they didn’t control for this birth-record situation. The Japanese diet was likewise praised based on the longevity of people in Okinawa. Same deal. And these diets were pushed, books were written. People were lectured about their bad eating habits because they didn’t follow this advice.
You might also be interested in The King of Junk Food Science is Out, also from SiGraybeard. (That’s food-science that is junk, not the science of Junk-food.) Things like the Mediterranean Diet were foisted on the public by bad statistical studies. Because it is easier to do bad statistics than be diligent, and in a world where you need to publish stuff you can. As long as you aren’t worried about things like the validity of your conclusions, or the repeatability of your findings. You just need to overlook things like systematic fraud that has creeped into your underlying data.