> Besides that, all my relatives lived close to 100

Were you there when they were born, so that you can verify their true age?

Can't speak for the one you're replying to, but when it's just about the age of 100 it's not particularly difficult to verify. Take my great-grandfather, for example, who died at nearly 100. I have photos with him and my father, when the latter was a child, and I've seen photos of my father from his whole lifespan of course. I have photos of my great-grandfather from way way back in time, with references (including newspaper articles with photos). And so on and so forth. There's no way his birth certificate and church records could have been faked. And that actually goes for my great-great-grandfather too.

On my mother's side, I was a little boy when I met my great-great grandmother who was already 90, and witnessed her living to, guess what, nearing that other age mentioned. And, again, there are records and photos going way back to when she was born.

At an old people's home nearby I got to know a gentleman for some years, he died this year at 99. Again there are records in numerous places documenting his age and where and when he was born (and he grew up nearby my grandfather's place). And at that same old people's home there's a vital lady who's 105, and, again, unless you believe all public documents and church records are fake, she's as real as it gets. She has a daughter who visits, she's in her seventies. That daughter has children of her own, and her children also have children.

It's when you get to all the 115-120 year olds in remote regions you start to see the fakes. And it's not difficult to spot when you look, the statistics are all skewed - unlike in places like most of Japan, just to get back to the original story.

But nobody is doubting that these people exist, or saying that their documents were faked maliciously. Back in my grandparents' time, they had a child, then a few years later they went to register the child, the clerk asked "how old is she?" and they said "7 or 8" when she was 11, for example.

My grandmother never knew her birthday, or her birth year. We just estimated, even though she was very much real.

Depends on where you live, I suppose. I know a lot about how it was done back as far as my great-greats and sometimes older, because the church records are meticulous and written with a lot of comments, and notes if there's been any kind of delays. And never would a child be registered years after birth.

It definitely depends where you live. My great grandparents wouldn't make the day's trek down the mountain to the city and sleep in the open just to register a child.

I don't doubt that the people you mentioning are the age they say they are, but even when there are multiple documents verifying somebody's age, they all take get data from a single original document. Apart from this I see things the same way as you've detailed.

The thing is - what I'm talking about is _not_ coming from a single original document. Yes, the birth certificate is a single document, but there's other documentation where children are mentioned. I looked up everything I could find about the 99 year old gentleman I mentioned, and because of certain "interesting" things about two of his grandparents the family had been traced by multiple sources before and through his birth. Newspapers were around, and photos too. The situation is different now than when people claimed to be extremely old back when the rage about super old people in certain east-European / west Asian regions began. Now we're talking about people born way into the 20th century, which means that for many regions in the world there aren't many options to fake it.