Social Fitness: Why Strong Relationships Are a Core Health Habit

Adults today report feeling more connected digitally but less fulfilled socially. Loneliness affects one in four adults in the UK, and is associated with increased cardiovascular risk, poorer mental health and reduced life expectancy (Holt-Lunstad, 2015).

However, social wellbeing is also a powerful positive force. Strong relationships improve immune function, reduce stress and even speed recovery from illness.

Why is this happening?

Humans are wired for belonging. Social connection activates the brain’s reward pathways and reduces threat perception. It increases oxytocin release, which supports trust, bonding and emotional regulation.

Conversely, loneliness increases cortisol and inflammatory markers, creating physiological wear and tear (Hawkley & Cacioppo, 2010). Social disconnection is therefore not simply emotional, it is biologically stressful.

Crucially, quality matters far more than quantity. Even small interactions with supportive individuals positively influence mood, stress and cognitive function.

This is further supported by Social Baseline Theory, which proposes that the human brain evolved with the expectation of social proximity and cooperative support (Beckes & Coan, 2011). When we feel socially supported, the brain reduces perceived environmental demands, lowering metabolic expenditure and stress signalling. Conversely, when support is absent, the brain assumes increased threat, amplifying vigilance and physiological load. In simple terms, connection reduces the cost of being alive; disconnection increases it.

What can we do about it?

Building social fitness involves nurturing the relationships that energise, support and challenge us. Prioritising meaningful conversations, participating in group activities, practising active listening and investing in a few high-quality bonds all strengthen social wellbeing.

Seeking connection doesn’t require extroversion; it requires intention. Even brief moments of authentic interaction can shift physiological state toward calm and safety.

Strong relationships aren’t just “nice to have, they’re one of the most powerful health behaviours we possess.

References:

Beckes, L., & Coan, J. A. (2011). Social Baseline Theory: The role of social proximity in emotion and economy of action. Social and Personality Psychology Compass.

Hawkley, L. C., & Cacioppo, J. T. (2010). Loneliness matters: A theoretical and empirical review of consequences and mechanisms. Annals of Behavioral Medicine, 40(2), 218–227.

Holt-Lunstad, J. (2015). Social relationships and mortality risk. Perspectives on Psychological Science, 10(2), 227–237.