Is cold exposure a viable lifestyle intervention for mental health? Reviewing evidence and mechanisms.

Cold exposure has gained substantial popularity as a wellness intervention, with growing public interest in its potential to alleviate symptoms of depression, anxiety, and stress-related disorders. While early observational studies and anecdotal reports suggest mental health benefits, the empirical evidence remains limited and methodologically inconsistent. This review critically evaluates the current state of research on cold exposure and mental health, with a focus on three key physiological systems implicated in its proposed effects: the catecholamine system, the hypothalamic-pituitary-adrenal (HPA) axis, and immune-inflammatory pathways. We examine evidence from randomized controlled trials (RCTs), observational studies, and translational models, highlighting both promising findings-such as acute mood enhancement and stress modulation-and persistent uncertainties regarding mechanism and clinical relevance. Despite theoretical plausibility and preliminary support, existing studies are hindered by small sample sizes, heterogeneous protocols, lack of active placebo controls, and selection bias stemming from self-selected, health-motivated participants. Psychological improvements reported in several studies have not been consistently linked to objective biological changes. We conclude that cold exposure represents a promising, yet still unproven, adjunct for mood regulation. Future research should prioritize standardized protocols, active control conditions, and recruitment of clinical populations to clarify its therapeutic potential and underlying mechanisms.