A new study found that interactions with friends and family may boost our immune system and reduce our risk of diseases such as heart disease.
The more time we spend alone may not just be detrimental to our mental health but our physical health too, new research suggests. According to a study, interactions with friends and family may boost our immune system and reduce our risk of diseases such as heart disease.
As part of the research, a team led by the University of Cambridge and Fudan University in China, examined blood samples donated by over 42,000 adults aged 40 to 69 years old. More specifically, they looked for groups of proteins in the blood known as proteomes.
They could then determine which proteins were present in higher levels among people who were classified as socially isolated or lonely, and how these proteins were connected to poorer health. Each individual was awarded a social isolation and loneliness score.
Social isolation was based on a number of factors including whether they live alone, how frequently they have contact with others socially, and whether they take part in social activities. And, as reported by Science Daily, the loneliness score was a subjective measure based on whether an individual feels lonely.
After adjusting for factors such as age, sex and socioeconomic background, the scientists discovered 175 proteins associated with social isolation and 26 proteins associated with loneliness. The majority of these proteins are produced in response to inflammation, viral infection and as part of our immune responses, as well as having been linked to cardiovascular disease, type 2 diabetes, stroke, and early death.
From here the team explored the causal relationship between social isolation and loneliness on the one hand, and proteins on the other. They found five proteins whose abundance was the result of loneliness.
Dr Chun Shen from Fudan University, explained: “We know that social isolation and loneliness are linked to poorer health, but we’ve never understood why. Our work has highlighted a number of proteins that appear to play a key role in this relationship, with levels of some proteins in particular increasing as a direct consequence of loneliness.”
Professor Jianfeng Feng from the University of Warwick continued: “There are more than 100,000 proteins and many of their variants in the human body. AI and high throughput proteomics can help us pinpoint some key proteins in prevention, diagnosis, treatment and prognosis in many human diseases and revolutionise the traditional view of human health.
“The proteins we’ve identified give us clues to the biology underpinning poor health among people who are socially isolated or lonely, highlighting why social relationships play such an important part in keeping us healthy.”
As an example, one of the proteins produced in higher levels as a result of loneliness was ADM. This protein has been previously linked to regulating stress hormones and social hormones such as oxytocin. Increased levels of ADM were linked to a greater risk of early death.
Professor Barbara Sahakian, from the Department of Psychiatry at the University of Cambridge, added: “These findings drive home the importance of social contact in keeping us well. More and more people of all ages are reporting feeling lonely. That’s why the World Health Organisation has described social isolation and loneliness as a ‘global public health concern’. We need to find ways to tackle this growing problem and keep people connected to help them stay healthy.”
According to the Office for National Statistics (ONS), 27 percent of adults in the UK reported feeling lonely in the period from December 2023 to January 2024. This includes people who felt lonely some of the time, often, or always
The study was published in the Nature Human Behaviour journal.