Summary: A major new study reports that the long-standing “unhappiness hump” in midlife — a peak in mental distress around middle age — has largely vanished. Instead, anxiety, depression, and stress are now highest among younger adults, while reported ill-being decreases steadily with age.
Analyses drawing on millions of responses across 44 countries indicate this shift is widespread. Researchers highlight economic pressures, gaps in mental health services, lingering effects of the COVID-19 pandemic, and increased social media exposure as plausible contributors. The findings raise urgent concerns about a growing mental health crisis among young people worldwide.
Key facts
- Historic change: Mental distress no longer peaks in midlife; it now tends to be highest among the young.
- Global evidence: The trend is supported by nearly 2 million respondents from 44 countries.
- Possible drivers: Economic fallout from the Great Recession, underfunded mental health systems, pandemic-related effects, and social media use.
Source: PLOS
Overview
Researchers led by David Blanchflower of Dartmouth College examined large-scale survey data and report that the familiar U-shaped pattern of wellbeing across the lifespan — where wellbeing falls into midlife and then rebounds in later life — appears to have shifted. Traditionally mirrored by an “ill-being hump” in midlife, this pattern has now been replaced by a monotonic decline in ill-being with increasing age, driven primarily by worsening mental health among younger cohorts.
Blanchflower and colleagues present these findings in PLOS One (published August 27, 2025). Their work builds on decades of research documenting age-related wellbeing patterns, but brings new evidence that younger generations are experiencing substantially worse mental health than previous cohorts at the same ages.
To reach these conclusions, the team first analyzed long-running national surveys from the United States and the United Kingdom. U.S. analyses used responses from more than 10 million adults surveyed by the Centers for Disease Control and Prevention between 1993 and 2024. U.K. analyses drew on data from the U.K. Household Longitudinal Study (2009–2023), which tracks roughly 40,000 households over time.
These national datasets showed a clear change in the age pattern of mental ill-being: instead of a midlife peak, ill-being now declines steadily with age. The authors note that levels of ill-being among people in their late 40s and older remained relatively stable, suggesting the disappearance of the hump results mainly from a deterioration in younger people’s mental health, not from improvements among middle-aged adults.
The researchers then extended their analysis to an international sample. Using the Global Minds study, which collected mental health data from nearly 2 million people across 44 countries between 2020 and 2025, they found the same age-related shift: the unhappiness hump is no longer apparent in these global data, and reported ill-being tends to fall as age increases.
Potential explanations
The authors caution that the causes of this generational shift are not yet settled. They discuss several plausible influences that may act separately or together:
- Economic fallout and weaker job prospects for younger adults following the Great Recession and subsequent economic instability.
- Insufficient funding and limited access to quality mental health care for young people in many countries.
- Pandemic-related disruptions, including social isolation, educational interruption, and prolonged uncertainty following COVID-19.
- Greater exposure to social media and digital environments that can amplify stress, anxiety, and social comparison.
The study emphasizes the need for further research to isolate which factors are most influential and to inform targeted policy responses.
Authors’ conclusion
The team states that this is the first paper to demonstrate that declining mental health among young people has shifted the age pattern of ill-being so that mental distress is now highest among the young and decreases with age in both the U.S. and the U.K. They conclude that this represents a substantial change from historical patterns and warn that a serious mental health crisis among young people requires urgent attention.
Funding: United Nations.
About this psychology and aging research news
Author: Hanna Abdallah
Source: PLOS
Contact: Hanna Abdallah – PLOS
Image: The image is credited to Neuroscience News
Original research (open access):
“The declining mental health of the young and the global disappearance of the unhappiness hump shape in age” by Alex Bryson et al., PLOS ONE
Abstract
The declining mental health of the young and the global disappearance of the unhappiness hump shape in age
Many studies have documented a U-shaped pattern in subjective wellbeing across the lifespan: wellbeing tends to decline into midlife and then rebound in older age, while measures of ill-being form a mirror-image hump that peaks in middle age. Using graphical and regression analyses of repeated cross-sectional data from the United States and the United Kingdom, the authors show that this long-standing empirical regularity has been replaced by a consistent decline in ill-being with age. The principal reason for this change is the deterioration of young people’s mental health both in absolute terms and relative to older cohorts. Pooling Global Minds data from 44 countries over 2020–2025 confirms that ill-being is no longer hump-shaped by age but instead decreases as age increases.