Loneliness hits young Australians, aged 15 to 24, harder than any other age group when it comes to their overall physical and mental wellbeing, Monash University researchers have found.
While older adults often get the most attention for being isolated, young people are actually losing more of their quality of life, such as feeling healthy, happy, and able to enjoy daily activities, because they feel lonely.
The study, published in Value in Health, and selected as one of the journal's 2026 Editor's Choice, analysed more than 53,000 observations from almost 22,000 Australians aged 15 and over, across four waves of the nationally representative Household, Income and Labour Dynamics in Australia (HILDA) Survey.
Researchers followed the same people over time, examining how changes in loneliness and social isolation were associated with changes in their health-related quality of life.
The analysis accounted for changes in circumstances including employment, income, physical and mental health conditions and major life events.
Loneliness alone was reported in 18 per cent of people aged 15 to 24, declining to 12 per cent among those aged 65 and over.
In contrast, social isolation alone was more common among older Australians.
Health-related quality of life was measured using standardised health utility values, which capture different aspects of health and wellbeing in a single score ranging from 1.0 (full health) to 0.0 (death).
Among 15 to 24-year-olds, loneliness was associated with a 0.079-point reduction in health utility - the largest reduction associated with loneliness across the age groups studied.
While social isolation was more common among older Australians, its strongest association with poorer health-related quality of life was seen among women aged 25 to 44.
Across all ages, compared with people experiencing neither, health utility was 0.020 points lower for social isolation alone and 0.061 points lower for loneliness alone - around three times the reduction.
The greatest reduction, 0.102 points, was seen among people experiencing both loneliness and social isolation.
This was greater than the sum of the individual reductions, suggesting a potential interaction between the two.
Lead researcher Dr Fikru Rizal, a research fellow at the Monash School of Public Health and Preventive Medicine Health Economics Group, said the findings challenged common assumptions about loneliness.
"Loneliness is often seen as an issue affecting older people, but we found its association with poorer health-related quality of life was greatest among young adults aged 15-24," Dr Rizal said.
"Loneliness is subjective and reflects how satisfied we feel with our social relationships, whereas social isolation is about objectively having fewer relationships and less frequent social contact.
"You can be surrounded by people and still feel deeply lonely, just as someone with relatively few social connections may not necessarily feel lonely.
"This reinforces the importance of recognising loneliness across the lifespan and designing responses that reflect the different ways people experience loneliness and social isolation."
Senior author Professor Cathy Mihalopoulos, from the Monash School of Public Health and Preventive Medicine Health Economics Group, said quantifying the quality of life impacts of loneliness and social isolation was particularly important for governments and health economists.
"Being able to quantify the impact of loneliness on health-related quality of life allows us to compare it with other health conditions and, importantly, we can also use this information to help assess whether programs designed to address it represent value for money," Professor Mihalopoulos said.
"These estimates can now be used in economic evaluations to help determine the potential health gains from programs targeting loneliness and social isolation and support better decisions about where healthcare resources are invested."
While the analysis accounted for a wide range of factors, the researchers noted that other unmeasured factors could also contribute to the relationship.
For example, loneliness or social isolation may in some cases reflect the severity of an underlying health condition.
The research forms part of Monash University's Connecting for Better Health project, which is examining the economic and social impacts of loneliness and social isolation and the interventions that could provide the greatest benefit to the community.
Read the research paper: https://doi.org/10.1016
A person with lived experience is available
