People Experience Recurring Life Crises at the Start of Each New Decade in Age
NYU Stern Professor Adam Alter and UCLA Anderson Professor Hal Hershfield find that people aged 29, 39, 49 and 59 are more likely to exercise vigorously, seek extramarital affairs or commit suicide
People are more apt to evaluate their lives as a chronological decade ends, and, as a result, more likely to make life-altering decisions.
In six studies looking at exercise, extramarital affairs and suicide rates among adults between the ages of 25 and 64, the researchers determine that certain numerical ages inspire greater self-reflection than others. Further, the authors suggest that people across dozens of countries and cultures are prone to making significant life decisions as they approach each new decade.
Background on the studies and key results:
- Studies 1 & 2: The authors examined data from 42,063 adults from more than 100 countries, who completed the World Values Survey and reported how often they questioned the meaning of life. They found that people who were entering a new decade in their lives are more likely to question whether their lives were meaningful.
- Study 3: Professors Alter and Hershfield categorized more than 8 million male users registered on a dating website that caters to people who are seeking extramarital affairs. They found that men aged 29, 39, 49 and 59 were nearly 18% more likely than men at other ages to register on the site.
- Study 4: The researchers examined the number of suicides per 100,000 individuals across the US from 2000 to 2011. Suicide rates were 2.4% higher among individuals whose age ended in a 9 than among people whose ages ended in any other digit.
- Study 5: The professors collected data from Athlinks, a website that compiles running race times, and found that runners ran about 2% faster at ages 29 and 39 than during the two years before and after those ages.
- Study 6: The authors examined the ages of 500 first-time marathon runners randomly drawn from the Athlinks website, and found 25% more “9-enders” than runners whose ages ended in any other digit.
The article, “People Search for Meaning When They Approach a New Decade in Chronological Age,” was published on November 17 in the Proceedings of the National Academy of Sciences.
Adam Alter is an Associate Professor of Marketing with affiliated appointment in the Psychology Department.