Summary: A new large-scale study shows that the long-standing “dip of unhappiness,” where depression peaked in middle age, has disappeared. Instead, younger people now report the highest levels of anxiety, depression, and stress, and stress levels continue to decline throughout life.
Data from millions of participants in 44 countries suggests this is a global trend. Researchers point to economic pressures, healthcare shortages, the aftermath of the pandemic, and social media as possible contributing factors, raising urgent concerns about the growing mental health crisis among young people.
Important facts:
- Historical change: Mental health problems are no longer very common in middle age, but are now most prevalent among young adults.
- Global data: An analysis of nearly 2 million people in 44 countries confirms this trend.
- Possible drivers: The effects of the recession, weak mental health systems, the fallout from the pandemic and social media.
Source: PLOS
A new survey-based study finds that the “anxiety threshold” (a widely documented increase in anxiety, stress, and depression with age that peaks in middle age and declines thereafter) may be disappearing, potentially as a result of declining mental health in young people.
David Blanchflower of Dartmouth College (US) and colleagues presented these findings in the open access journal PLOS One on August 27, 2025.
Since 2008, a U-shaped trend in health with age has been observed in developed and developing countries around the world, with health declining from childhood to age 50, before generally recovering in old age. The data also show a similar increase in stress or unhappiness.
Recent data point to a global decline in youth well-being. However, most studies do not directly address the potential consequences of rising unhappiness.
To gain insight into the relationship between age and mental health, Blanchflower and his team examined extensive survey data from both the United States and the United Kingdom. In the U.S., they analyzed responses from more than 10 million adults gathered by the Centers for Disease Control and Prevention (CDC) between 1993 and 2024. These surveys included questions focused on participants’ emotional well-being, providing a broad view of mental health trends across several decades.
In the United Kingdom, the researchers used data from the U.K. Household Longitudinal Study, an ongoing project that tracks the lives of 40,000 households. Covering the period from 2009 to 2023, this dataset offered detailed information on individuals’ mental health and life experiences over time. By comparing patterns across these two large and diverse populations, the team aimed to identify common trends and better understand how mental health evolves throughout different stages of life.
The analysis shows that in the US and UK, the “comfort hump”, which typically reduces discomfort/unhappiness across the lifespan, has disappeared. There was no significant change in discomfort levels among people aged 40 and over. The disappearance of the “compassion hump”, however, appears to be due to a decline in mental health among young people.
The researchers then analyzed data from nearly 2 million people in 44 countries, including the United States and the United Kingdom, taken from a mental health study called Global Minds. The data, which covers the period from 2020 to 2025, suggests that unhappiness has gone down around the world.
The reasons for the disappearance of the unhappiness threshold are unclear. The authors have suggested several possibilities, including the long-term effects of the Great Recession on youth employment prospects, underfunding of mental health services, mental health challenges resulting from the COVID-19 pandemic, and increased social media use.
More research is needed to determine whether these or other factors play a role.
The authors added: “Our paper is the first to show that the decline in young people’s mental health in recent years means that in both the US and the UK, mental distress is highest among young people and tends to decline with age.
This is a huge shift from the past, when mental health problems peaked in middle age. The reasons for this shift are controversial, but we are concerned about the serious mental health crisis among young people today that needs to be addressed.
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 StackZone Neuro
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 deterioration of youth mental health and the global disappearance of the hump of unhappiness in later life
Several studies show that subjective well-being follows a U-shaped curve with age, falling until middle age and then recovering. Discomfort follows an inverted curve.
Using graphical and regression analyses of repeated microdata from the United States and the United Kingdom, we show that this empirical regularity is replaced by a radical decrease in stress with increasing age.
The reason for the change is the deteriorating mental health of young people, particularly and relative to older people.
By collecting Global Minds data from 44 countries, including the United States and the United Kingdom, over the period 2020-2025, we confirmed that stress is no longer limited to age, but now decreases with age.
