A study by The University of Cambridge has found almost a quarter of adults have felt lonely during the coronavirus lockdown.
The most affected age group were the under 24s - with 44 per cent feeling lonely, followed by those aged 25 to 34.
The university is working with the Mental Health Foundation on the affects the pandemic has on wellbeing.
Dr Tine Van Bortel from the Institute of Public Health at the University of Cambridge is leading research on loneliness in lockdown.
She spoke to ITV News Anglia's Becky Jago.
How is lockdown affecting our mental health?
Adults aged over 55 said they felt lonely as a result of coronavirus
Cambridge academics say they're concerned about the long-term risk to our mental health.
“It might feel surprising but what our research shows is that the group most likely to be experiencing these feelings are young people", said Prof Tine Van Bortel from the University of Cambridge.
"It is worrying that close to half of them said they are concerned about feeling lonely, and special attention should be given to this as we know that young people are at higher risk of self-harm and suicide.
"However we shouldn’t forget that loneliness is also clearly affecting very large numbers of people of all ages. Loneliness is a major problem and has the same impact on mortality as smoking 15 cigarettes a day, making it even more dangerous than obesity."