Exploring participant experiences with the autoimmune protocol (AIP) diet in rheumatoid arthritis: a longitudinal qualitative study.

Social exclusion refers to the negative interpersonal experience in which an individual is rejected, ignored, or ostracized by other individuals or groups (). In the unique and critical developmental stage of college, peer acceptance plays a vital role in students’ psychological adjustment and personality formation. However, college students are precisely a high-risk group for social exclusion, as they have left their original family and friendship support systems and need to rebuild social relationships in an entirely new environment. Research has shown that social exclusion exerts a broad range of detrimental effects on college students’ mental health and development. It not only triggers intense negative emotions, such as depression (Lui et al., 2020), but also leads to decreased self-esteem (). In the long term, persistent social exclusion significantly elevates college students’ levels of anxiety and negative affect (), and may impair academic performance through damage to executive functions (). Given the multiple adverse impacts of social exclusion on college students’ development, a thorough investigation of its underlying mechanisms is of critical theoretical and practical significance for safeguarding college students’ mental health and designing effective psychological interventions. Meaning in life refers to the extent to which individuals perceive their lives as meaningful, including their sense of life purpose and primary goals (). Research indicates that social relationships serve as a crucial foundation for meaning in life (; ), and social support can enhance individuals’ existential experience by increasing feelings of happiness and satisfaction (). However, social exclusion poses a serious threat to this process, as it can trigger cognitive deconstruction in individuals, leading them to fall into a state of meaninglessness (). Such exclusion experiences impair individuals’ sense of control over their lives and their self-worth, thereby directly reducing their level of meaning in life (). Further studies have shown that the loss of meaning resulting from social exclusion may escalate into extreme consequences such as suicidal ideation (). Based on the above, the present study hypothesizes that social exclusion is negatively correlated with meaning in life among college students. The mechanism by which social exclusion affects college students’ meaning in life remains to be further explored, and loneliness may serve as a mediating factor. Loneliness refers to an individual’s subjective perception of being isolated, accompanied by a sense of separation from others and negative emotional experiences arising from unmet needs for interpersonal connection (). According to the need-to-belong theory (), establishing and maintaining stable, positive interpersonal relationships is a fundamental human need. When college students experience social exclusion, their need for belonging is thwarted, making it difficult for them to perceive a sense of purpose and significance from social connections (; ), thereby increasing their level of loneliness (). From an existential perspective, constructing and maintaining meaningful connections is a fundamental drive that enables individuals to transcend personal loneliness and affirm their own worth (). For this reason, interpersonal relationships serve as a crucial source of meaning in life for college students. Without such positive connections, persistent loneliness may lead students into existential anxiety, causing them to feel unwanted and misunderstood, and consequently leading them to deeply question the value of their existence and the purpose of their lives, which directly reduces their sense of meaning in life (). In summary, the present study hypothesizes that loneliness mediates the relationship between social exclusion and meaning in life among college students.