TIL that more than 1 in every 365 people die on their birthday, and nobody’s sure why

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A study by Swiss researchers has generated a startling statistic – you are 14% more likely to die on your birthday than on any other day of the year. But why should that be?

As the researchers put it, “birthdays… appear to end up in a lethal way more frequently than expected .”

This is not a joke. The study was carried out by legitimate scientists who analysed data from 2.5 million deaths in Switzerland between 1969 and 2008.

There are a number of hypotheses which may explain the finding.

Perhaps some people close to death “hang on” until their birthday, to reach another milestone? Or perhaps a significant number of people take greater risks on their birthdays, like driving home from their own parties drunk?

But Professor David Spiegelhalter, a statistician from Cambridge University, says the Swiss data does not support the “hanging on” theory.

“They don’t find any dip before so there’s no holding on,” he says, “and they don’t find any blip after, so there’s no jumping the gun. It’s purely a birthday effect.”

The Swiss data, he says, suggests “something on your birthday kills you”.

BBC News