In older adults in Japan, reducing social isolation is associated with a small increase in survival time, particularly for those with lower education or income levels.
Mechanism
Synthesis from 1 study
When lonely older adults in Japan gain more social connection, their bodies produce less stress hormone, which helps their heart and immune system work better — especially helping those with less money or education, who were more likely to be lonely and at higher risk of dying early.
Most probable mechanism
When older adults feel less alone, their bodies produce less of the stress hormone cortisol, which helps their immune system work better and their heart and blood vessels stay healthier, letting them live longer — especially for those who were poorer or had less education and were more likely to be isolated.
Reduced social isolation decreases activation of the hypothalamic-pituitary-adrenal (HPA) axis, lowering circulating cortisol levels
Lower cortisol levels reduce systemic inflammation and improve endothelial function in blood vessels
Improved immune and vascular function reduces susceptibility to infections, cardiovascular events, and age-related organ decline
Evidence from Studies
Supporting (1)
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Contradicting (0)
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