The widely accepted notion that happiness follows a U-shaped trajectory—with peaks in early and late life—may be misleading.

This idea gained traction from an original study by researchers David Blanchflower and Andrew Oswald, based on data from 500,000 individuals in 2008. Since then, it has permeated popular culture through mainstream literature.

However, researchers Fabian Kratz and Josef Brüderl at Ludwig Maximilian University in Munich argue that this belief may not hold true.

Kratz feels compelled to reevaluate the U-curve claim. The researchers analyzed self-reported happiness data from 70,922 adults who took part in the Socio-Economic Panel Survey in Germany from 1984 to 2017, modeling how happiness evolved over individuals’ lifetimes.

Contrary to the U-shaped model, they discovered that happiness typically declines during adulthood, only beginning to rise again in the late 50s.

Kratz believes that prior research may have drawn erroneous conclusions by oversimplifying the happiness trajectory and neglecting deaths due to suicide or illness. “It can seem that happiness increases after a certain age simply because those who are unhappy have already passed away,” Kratz explains.

“In the social sciences, there’s been considerable debate over conflicting findings—results often evaporate with new data collection,” says Julia Roller at the University of Leipzig. “Yet, another overlooked issue is that researchers may analyze data in ways that are systematically flawed. This can yield replicable findings, but still mislead.”

Others posit that these findings raise important questions. “This study provides an excellent opportunity to reconsider our understanding in this field,” remarks Philip Cohen at the University of Maryland, highlighting the need to explore why our happiness shifts throughout life and how we can ameliorate low points. Both Kratz and Brüderl express a desire to avoid speculation on the reasons behind these observed changes.

Oswald notes that the study presents “interesting results” worthy of consideration, but he emphasizes that factors such as marriage and income are beyond his control.

Furthermore, he points out that the study focuses on a single country, leaving it unclear whether these results are applicable elsewhere. Kratz suggests this may provide a useful foundation for future research. Notably, the findings could inform policy. “Previous scholars argued for the importance of proactive policies to help individuals navigate mid-life crises,” Kratz mentions. “While we do not dismiss this urgency, our results indicate that addressing declining well-being in older adults should be a priority.”

Do you need someone to talk to? In the UK, contact Samaritans at 116123 (Samaritans.org); in the US, reach out to the Suicide and Crisis Lifeline at 988 (988lifeline.org). For services in other countries, visit bit.ly/suicidehelplines.