For years, researchers have observed a curious pattern in well-being known as the “unhappiness hump.”
Across many countries, surveys showed that people’s happiness typically followed a U-shaped curve: high in youth, dipping in midlife with more stress and worry, and then rebounding again in older age.
But new research suggests this pattern may have vanished—and not for good reasons.
A new study, led by David Blanchflower of Dartmouth College and published in PLOS One, found that the unhappiness hump has largely disappeared in both the U.S. and the U.K., and may no longer exist worldwide.
Instead of middle-aged adults being the most stressed or unhappy, younger generations now report much higher levels of mental distress, while older adults are faring relatively better.
The researchers examined decades of survey data. In the U.S., they analyzed responses from more than 10 million adults collected by the Centers for Disease Control and Prevention between 1993 and 2024.
For the U.K., they studied data from the U.K. Household Longitudinal Study, which tracks 40,000 households and spans from 2009 to 2023.
In both countries, they found that levels of stress, depression, and unhappiness no longer peaked in midlife. Instead, ill-being steadily declined with age, meaning that younger people were now reporting more mental health struggles than those in their 40s, 50s, and beyond.
Older adults’ well-being has remained largely stable, so the shift appears to be driven by worsening mental health among the young.
To see if this trend was broader, the team also analyzed data from nearly 2 million people in 44 countries as part of the Global Minds survey, covering 2020 through 2025. The results suggested the unhappiness hump has indeed disappeared on a global scale.
Why this is happening remains unclear, but the authors suggest several possibilities. The long-term impacts of the Great Recession may have hurt job prospects for young people. Mental health services remain underfunded in many countries. The COVID-19 pandemic created new challenges, while the rise of social media may also be playing a role.
“Our concern is that today there is a serious mental health crisis among the young that needs addressing,” the researchers wrote. “In the past, mental ill-being peaked in middle age. Now, it is highest among the young and declines with age.”
This shift marks a profound change in how happiness and well-being unfold across a lifetime, highlighting the urgent need for greater support for younger generations.
If you care about mental health, please read studies about cannabis use disorder linked to increased risk of mental diseases and some mental health drugs can cause rapid weight gain.
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