Summary: A coordinated analysis of nine long-term studies shows that loneliness follows a clear U-shaped pattern across adulthood: it is higher in young adults and older adults and reaches its lowest point in middle age. The research also pinpoints consistent risk factors for persistent loneliness—such as social isolation, lower educational attainment, and physical limitations—and underscores the need for public health responses comparable to other major health risks.
This study highlights loneliness as a widespread, cross-national issue with documented links to poorer physical and mental health. The authors call for targeted interventions and routine assessment of loneliness in clinical and community settings to better identify and support people at risk.
Key Facts:
- U-shaped Loneliness Curve: Loneliness declines from young adulthood into middle age and then increases again in older adulthood.
- Global Consistency: The U-shaped pattern was observed across nine longitudinal datasets from multiple countries, indicating a broadly consistent life-course trend.
- Health Consequences: Loneliness is linked to significant health risks; experts recommend recognizing and addressing loneliness as part of preventive care.
Source: Northwestern University
Overview of findings
A Northwestern Medicine team led by Eileen Graham analyzed nine pre-pandemic longitudinal studies spanning multiple countries and age ranges to map how loneliness changes across the adult lifespan. The coordinated analysis found a reliable U-shaped trajectory: higher loneliness in younger adults, a pronounced dip through middle adulthood, and a consistent rise in later life.
“What was striking was how consistent the uptick in loneliness is in older adulthood,” said Eileen Graham, associate professor of medical social sciences at Northwestern University Feinberg School of Medicine. The team emphasized that loneliness is not simply a private emotional experience but one with measurable consequences for health and longevity.
Public health leaders have compared the mortality risk associated with chronic social isolation and loneliness to well-known hazards such as daily smoking. That magnitude of risk has led to calls for systematic efforts to identify and reduce loneliness at the population level.
Graham and colleagues suggest that reducing social disparities across the life course—through policies and interventions that improve social connectivity, education access, and physical functioning—could help lower persistent loneliness, especially among older adults.
The study’s authors also propose that routine health screenings could include simple assessments of loneliness, which would help clinicians identify people who might benefit from social supports or referrals to services that foster connection.
The full study is scheduled for publication in the journal Psychological Science.
Risk factors linked to persistent loneliness
Across the pooled datasets, people with higher and more persistent levels of loneliness tended to share several characteristics: they were more often women, experienced greater social isolation, had lower educational attainment and income, reported more functional limitations, were divorced or widowed, smoked, or had poorer cognitive, physical, or mental health. These factors were associated with higher baseline loneliness, even if they did not always change the overall life-course trajectory.
Why does loneliness dip in middle adulthood?
The analysis did not set out to explain causation, but the researchers noted plausible social dynamics that may help account for lower loneliness in midlife. Middle-aged adults often engage in multiple structured social roles—such as employment, parenting, and established friendships—that provide routine social contact and a sense of belonging. However, the relationship between social contact and loneliness is complex: frequent interaction does not automatically prevent loneliness, and some people with limited social contact do not feel lonely.
Why are young adults and older adults more vulnerable?
Young adulthood often involves major life transitions—completing education, starting careers, forming new social circles and romantic relationships—that can heighten feelings of uncertainty and disconnection. By contrast, as people move into and through midlife they often settle into more stable roles and social networks. For older adults the loss of partners, retirement, declining health, reduced mobility, and shrinking social networks can increase the risk of persistent loneliness. The authors note that finding meaningful social contact—whether through friendships, community activities, or formal programs—can help reduce loneliness for older adults, particularly those who are not partnered.
About this research and reporting
Author: Kristin Samuelson
Source: Northwestern University
Contact: Kristin Samuelson – Northwestern University
Image: The image is credited to Neuroscience News
Original Research: Closed access. “Do We Become More Lonely With Age? A Coordinated Data Analysis of Nine Longitudinal Studies” by Eileen Graham et al., Psychological Science.
Abstract
Do We Become More Lonely With Age? A Coordinated Data Analysis of Nine Longitudinal Studies
Loneliness is a common experience with demonstrable negative impacts on well-being and physical health. To clarify how loneliness evolves across the adult lifespan and which factors are associated with those changes, researchers performed a coordinated analysis of nine longitudinal studies that together included 128,118 participants aged 13 to 103 from more than 20 countries. Using harmonized measures and statistical models, the team charted loneliness trajectories and evaluated predictors.
Results consistently revealed a U-shaped curve: loneliness tends to fall from young adulthood into midlife and then rises again in older adulthood. Several baseline characteristics—such as sex, marital status, physical functioning, and education—were associated with overall loneliness levels, although few factors substantially altered the shape of the trajectory. These findings emphasize loneliness as a dynamic, life-course issue and support the development of targeted strategies to reduce social disparities and persistent loneliness across adulthood.