Social support as a comfort or an encouragement: A systematic review on the contrasting effects of social support on cardiovascular reactivity.

The stress-buffering hypothesis (Cohen & McKay, 1984, Handbook of psychology and health IV: Social psychological aspects of health (pp. 253-256). Hillsdale, NJ: Lawrence Erlbaum) suggests that one way social support enhances health is by attenuating cardiovascular reactivity (CVR) to stress. Research that has tested this hypothesis has reported inconsistent findings. In this review, we systematically reviewed those findings and proposed a dual-effect model of social support and CVR as a potential explanation for the inconsistency in the literature. Specifically, we proposed that when participants are more engaged during a stressor, social support acts primarily as social comfort, attenuating CVR; and when participants are not engaged, social support acts primarily as social encouragement, elevating CVR.