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Research -

In 2012, researchers at the Psychiatric University Hospital and the University of Zurich published a study that analyzed data to estimate the likelihood people dying on their birthdays. The study compiled data from 1969 to 2008.

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Study results -

The study found that: "In general, birthdays ... appear to end up in a lethal way more frequently than expected."

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Study results -

In total, according to the study, people were 13.8% more likely to die on their birthday.

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Study -

Another study, conducted by the University of Chicago in 2014, found that the likelihood of people dying on their birthdays was slightly lower, at 6.7%. But they also found that age plays a big part in the stats.

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50+ -

Surprisingly, once you're over 50 the likelihood of dying on your birthday actually goes down.

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Age group -

But the news is not so great for those between 20 and 29. The study found that people in this age group are 25.39% more likely to die on their birthday.

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Weekend -

And this number skyrockets for those whose birthdays fell on a weekend, where the likelihood soars up to 48.3%!

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Reason -

There is a major risk factor that impacts these results: the fact that people turning 21 are more likely to binge drink, which will consequently influence their behavior.

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"Anniversary reaction" -

The U.S. Department of Veteran Affairs and the National Center for PTSD have actually looked at the effects of anniversaries, and how they exacerbate several symptoms and feelings. These include depression and anxiety, among many others.

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Reminder -

We usually reflect on our lives and are reminded that we're closer to the end. This can trigger a number of feelings that can indeed affect our health.

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Stress -

Birthdays can be stressful, for various reasons. Stress has been linked to a number of cardiovascular-related deaths, so it's easy to see how one can lead to the other.

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Broken heart -

A broken heart can be fatal. For instance, the first birthday without a loved one, who's no longer present for whatever reason, can cause a lot of sadness and stress.

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Broken heart -

Grief can make the body pump chemicals such as epinephrine and adrenaline to the heart. This can be fatal, particularly if the person has any pre-existing heart conditions.

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Too much happiness can be fatal too -

Yes, a strong emotional trigger such as extreme happiness can cause "happy heart," or Takotsubo syndrome, also known as stress cardiomyopathy.

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Happy medium -

"Perhaps both happy and sad life events, while inherently distinct, share final common pathways in the central nervous system output," says Christian Templin, a cardiologist at University Hospital Zurich.

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Circannual rhythm -

You're probably familiar with the circadian rhythm, which lasts 24 hours. But some scientists believe that there is also a human circannual rhythm, which lasts about one year.

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Circannual rhythm -

Researchers at the National Academy of Medical Sciences of Ukraine also found that people not only were likely to die on their birthday, but that they were also more likely to die on their birthday month.

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Circannual rhythm -

The researchers "hypothesize that 'birth stress' might be imprinted in a structure of the biological rhythms of the organism, thus resulting in periodic changes of vulnerability and survivability during the course of the IAC (individual annual cycle)."

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The death postponement hypothesis -

The "mind over matter" hypothesis must also be considered in this context. Several studies point to the fact that, in some cases, people are able to postpone their deaths until after a certain event.

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The death postponement hypothesis -

Researchers looked at the mortality rates around the Harvest Moon Festival in China. They found that the number of deaths went down leading up to the festival, and then peaked after it took place.

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The date you're more likely to die -

According to data from 57 million death certificates, people are most likely to die of natural causes on January 1.

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The day of the week you're more likely to die -

Monday might have a bad rep, but according to data from the Centers for Disease Control and Prevention, Saturday is the day people die the most.

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Famous people -

Now, let's look at some of the famous faces who passed away on their birthdays.

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William Shakespeare -

It is believed that the famed playwright died on his 52nd birthday, on April 23, 1616. Though the day he was actually born is still up for debate.

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Ingrid Bergman -

The iconic Swedish actress died on her 67th birthday, on August 29, 1982.

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Raphael -

The famous Italian Renaissance painter is said to have died on his 37th birthday.

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Machine Gun Kelly -

The infamous American gangster, whose real name was George Kelly Barnes, died in July 18, 1954, which was his 59th birthday.

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Gertrude Astor -

The American actress was born on November 9, 1887, and passed away on her 90th birthday on November 9, 1977.

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Sidney Bechet -

The jazz musician left us on his 62nd birthday on May 14, 1959.

Sources: (Grunge)

See also: Strange celebrity deaths you probably don't know about

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