According to new research, staying connected with friends and family is not only good for mental health, but it may also protect against diseases like heart disease, stroke and type 2 diabetes.

Researchers from the University of Cambridge, UK, and Fudan University, China, analyzed blood samples from more than 42,000 adults in the UK Biobank study.

They found that social isolation and loneliness are linked to specific proteins in the blood that affect inflammation, immune response and stress regulation – all factors associated with serious health conditions.

Social isolation refers to limited social interaction and participation in activities, while loneliness is an individual feeling of being alone. Although the two are different, the study published in Nature Human Behavior found significant overlap in the proteins associated with both.

The researchers identified 175 proteins associated with social isolation and 26 proteins associated with loneliness, with 85% of these proteins overlapping. These proteins are involved in inflammation, viral responses, and diseases such as diabetes and cardiovascular problems.

One key protein identified was ADM, which regulates stress and social hormones such as oxytocin, known as the ‘love hormone’. Higher ADM levels were associated with smaller brain areas responsible for emotional and social processing and an increased risk of early death.

Another protein, ASGR1, was linked to higher cholesterol and greater risk of heart disease. Other proteins identified have been linked to insulin resistance, artery damage and even cancer progression.

Dr Chun Shen of the University of Cambridge said, “We know that social isolation and loneliness affect health, but we have never fully understood why. These proteins give us important information about how social connections affect our organisms. How do they affect science?

The study also shed light on how loneliness affects the brain. Increased levels of ADM were associated with decreased brain volume in areas controlling emotions and physical awareness. “Social isolation and loneliness are global public health concerns. Addressing them could significantly improve health outcomes,” said Barbara Sahakian of the University of Cambridge.

The findings highlight the importance of staying socially connected not only for emotional well-being but also for long-term physical health. Researchers are suggesting investing in community programs, social activities, and support systems as these can play an important role in reducing loneliness and improving overall health outcomes.