Loneliness has been linked to an increased risk of heart disease, stroke, and infections, according to new research that highlights the biological mechanisms behind the health risks associated with social isolation. Scientists from the University of Cambridge and Fudan University in China have found that certain blood proteins are elevated in individuals who experience prolonged loneliness, potentially raising their risk for several health conditions. The study, covered by The Times, UK, reveals how social isolation can influence blood protein levels, which in turn may lead to various diseases.
The research, which analyzed blood samples from over 42,000 adults in the UK Biobank, identified five proteins with a direct causal link to loneliness. Some of these proteins are involved in regulating cholesterol and insulin resistance, key factors that can lead to heart disease and diabetes. The World Health Organization (WHO) has long recognized loneliness as a global public health concern, and this study further emphasizes the need to understand the biological impact of social isolation on health.
Professor Barbara Sahakian from the University of Cambridge stressed the importance of social contact in maintaining health. “More and more people of all ages are reporting feeling lonely,” she said. “We need to find ways to tackle this growing problem and keep people connected to help them stay healthy.”
Among the blood proteins identified, adrenomedullin (ADM) plays a key role in the body’s response to stress, while ASGR1 is linked to higher cholesterol levels and an increased risk of heart disease. Another protein associated with loneliness has been found to contribute to insulin resistance, which is a precursor to type 2 diabetes.
Dr. Chun Shen, one of the lead researchers, explained that the study provides insight into why loneliness impacts health, shedding light on the specific biological changes that occur in the body. “We’ve never understood why social isolation and loneliness are linked to poorer health, but our work has highlighted a number of proteins that appear to play a key role in this relationship,” he said.
This research adds to a growing body of evidence suggesting that loneliness can have a similar impact on health as smoking 15 cigarettes a day. In fact, a previous study published in 2023 found that pensioners in China who had regular social interactions lived longer than those who were socially isolated. The findings underscore the importance of fostering social connections to improve overall well-being and longevity.
