Background: Suicide among emerging adults has become a significant global public health concern. Suicidal ideation is the prerequisite for suicide, and social support is recognized as a key protective factor against suicidal ideation. However, the relationship between the strength and consistency of social support and suicidal ideation among undergraduate students remains unclear. This study synthesized empirical studies to quantify the relationship between social support and suicidal ideation among undergraduate students and determine the different correlations between various sources of social support and suicidal ideation. Methods: A systematic review and meta-analysis was conducted following PRISMA 2020 guidelines. Five electronic databases (Web of Science, Scopus, PubMed, ProQuest, and ScienceDirect) were searched for studies published from 2016 to 2025. Eligible studies reported quantitative associations between social support and suicidal ideation among undergraduate students. Correlation coefficients were transformed using Fisher’s z and pooled using a random-effects model. Heterogeneity was evaluated using Cochran’s Q and I2 statistics. Risk of bias assessments, moderator analysis, sensitivity analysis, subgroup analysis, and publication bias assessments were conducted. Results: Fifteen studies with sixteen independent effect sizes and more than 26,000 participants were included. The meta-analysis showed a moderate negative association between social support and suicidal ideation (pooled r = −0.33, 95% CI −0.40, −0.25) under a random-effects model. A high heterogeneity was observed among studies (I2 = 97%, p < 0.001). There are no studies classified as having a high risk of bias. The standardized sample size demonstrated a significant moderating effect (β = 0.2568, p = 0.0022). Sensitivity analysis confirmed the stability of the pooled effect. Subgroup analysis indicated that the strength of the association between social support and suicidal ideation did not differ significantly between Asian and non-Asian studies. No significant publication bias was detected (Egger’s p = 0.19). Narrative synthesis further suggested that family support showed the most consistent protective association compared with friends’ support and support from others. Conclusions: Social support is moderately and consistently associated with reduced suicidal ideation among undergraduate students. These findings highlight social connectedness, particularly family support, as a central interpersonal protective factor and strengthen social support’s role in university suicide prevention initiatives.
Chen et al. (Thu,) studied this question.