Overall, emotional and social loneliness and their associated factors: a large-scale cross-sectional study of young and middle-aged adults in Germany

Background Loneliness is increasingly recognized as a major public health concern, yet little is known about the distinct patterns and associated factors of emotional and social loneliness during young and middle adulthood. This study examined age-related differences in overall, emotional, and social loneliness and associated sociodemographic, social, health-related, and personality factors among adults in Germany. Methods We analysed nationally representative data from the German Family Demography Panel Study (FReDA), including 14,443 adults aged 18 to 51 years. Loneliness was assessed using the validated De Jong Gierveld Loneliness Short Scale, distinguishing overall, emotional, and social loneliness. Multivariable regression models examined associations with sociodemographic, social, health-related, and personality factors. Analyses were stratified by age and gender. Results High levels of loneliness were common, with 24.3% of participants reporting intense emotional loneliness, 29.6% intense overall loneliness, and 35.8% intense social loneliness. Overall loneliness remained relatively stable across age groups. In contrast, emotional loneliness was lower in older age groups, while social loneliness was higher. Social relationships showed some of the strongest associations with loneliness, particularly social loneliness: discussing personal matters within one’s social network (β = -0.32, 95% CI -0.37 to -0.28) and having a partner (β = -0.21, 95% CI -0.26 to -0.16) were associated with lower social loneliness, while first-generation migration background was associated with higher social loneliness (β = 0.31, 95% CI 0.24 to 0.38). Mental health burdens were consistently associated with higher loneliness, especially emotional loneliness, with depressed mood showing the strongest association (β = 0.22, 95% CI 0.17 to 0.27). Among personality traits, agreeableness was associated with lower social loneliness (β = -0.19, 95% CI -0.22 to -0.17), whereas neuroticism was associated with higher emotional loneliness (β = 0.17, 95% CI 0.14 to 0.20). Gender differences were generally small, as were associations with physical health conditions. Conclusions Loneliness in young and middle adulthood is multidimensional, with emotional and social loneliness showing distinct age-related patterns and associated factors. Social relationships showed some of the strongest associations with lower loneliness, while mental health burdens and first-generation migration background were associated with higher loneliness. Public health strategies may benefit from considering different loneliness dimensions and psychosocial contexts.