You are more likely to die on your birthday than the other 364 days of the year.

Every year we blow out the candles to celebrate that we have circled the sun again; that we are still alive. For most, it is an early and joyful date, but the statistic hides a disturbing reality: the probability of dying is significantly higher on our birthday.

The birthday effect. This is the name of this curious statistical phenomenon. It has been observed that mortality increases on the date of the birthday and also in the days close to it, both before and after. Although there are no figures at a global level, numerous studies have been carried out in different populations and in all of them an increase in deaths has been seen on these dates. Because?

Studies. The birthday effect has been studied in different populations such as the United Kingdom, Switzerland, the United States, Ukraine, Russia and Japan. With more than 40 years of data, Switzerland has one of the largest studios about this phenomenon and the conclusion is devastating: there is an excess of deaths of 13.8% on birthdays. In the United States, data on more than 25 million deaths were verified and an excess mortality of 6.8% was detected on birthdays and nearby days. The most striking case is that of kyivwith an excess of deaths of 44.4%, although the sample was smaller (just over 100,000 deaths in a ten-year period).

Differences by gender. One of the first studies that was done on this phenomenon was in California in 1992 and detected a curious difference between genders: men died more in the week before their birthday and women in the week after. Other studies, such as the one we mentioned from kyiv, have also seen a difference between genders, but focused on quantity: 44.4% of male deaths and 36.2% of female deaths.

Age and seasonality. Other relevant patterns have been identified. In the United Statesexcess mortality exceeded 25% in the 20 to 29 year old group. Another revealing fact is the peak deaths on 21st birthdaywhich is just the legal drinking age. There are also times of the year where this effect is clearermainly the month of January.

The causes. The main cause is related to typical risk activities in celebrations, mainly the consumption of alcohol and drugs that leads to overdoses or traffic accidents. It is also common for this date to generate an effect known as “birthday depression”a state associated with loneliness, trauma or fear of finitude, which increases suicide rates. In Japan, The risk of suicide increases by 50% on the birthday. Also has been studied in Hungarywhere the risk is 40% higher.

Physiological and psychological theories. There are studies that have attempted to relate this excess mortality to physiological causessuggesting the existence of annual biological rhythms that could modulate the risk of death throughout the year. Others point to psychological or psychosomatic reasons: from seriously ill people who “hold on” until their birthday or deaths generated by their own awareness of mortality and the stress that this causes.

Image | Imants Kaziļuns in Unsplash

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