A new systematic review and meta‑analysis finds that people who experienced adversity in childhood—such as abuse, neglect or serious family disruption—are more likely to feel lonely later in life. Pooling the best available data, the authors report a moderate link between the total amount of childhood adversity and loneliness in adulthood.  

What the study did

Researchers combed eight major databases and screened 3,689 unique papers. Twenty studies met the inclusion criteria for the review, and seven of those (3,255 participants in total) provided enough numbers to combine statistically. The team preregistered its protocol and followed standard systematic‑review methods (see the PRISMA flow diagram on page 3 of the paper).  The review covered common “adverse childhood experiences” (ACEs)—physical, sexual and emotional abuse; physical and emotional neglect; parental separation/divorce; family conflict; and witnessing domestic violence—and required that studies measured loneliness using validated tools.  

Key findings

• Overall link: Across studies, more childhood adversity was associated with more loneliness in adulthood (correlation r = 0.30; 95% CI 0.22–0.37). In plain terms, that’s a moderate relationship. The authors also estimated a prediction interval (0.04–0.52), indicating the direction of the effect is likely to be the same in future studies, even if the size varies.  
• Which experiences matter: Significant associations with adult loneliness were seen for sexual abuse, physical abuse, physical neglect, emotional abuse, and emotional neglect. Family conflict and parental separation/divorce were also linked to later loneliness, while witnessing domestic violence was not significantly associated in the limited data available.  
• Who is most affected: Subgroup analyses found no meaningful differences by age, gender, age group, continent, or by which standard questionnaires were used—suggesting the link shows up broadly across populations and measures.  

Caveats

The authors note high variation between studies and that only seven contributed data to the meta‑analysis, so estimates should be interpreted with caution. Tests for publication bias were not significant, but the small number of studies limits confidence in those tests. The field also lacks consensus on how to define and measure specific ACE types, which makes comparisons harder.  

Why it matters

Loneliness is more than “feeling alone”—it’s the distress that arises when our relationships fall short of what we need. This review suggests that preventing and responding to childhood adversity may also help reduce loneliness decades later. For clinicians, the authors recommend asking about loneliness during assessments of people with a history of ACEs and offering supports that build social skills and connections.  

The bottom line

Adverse experiences in childhood can echo into adulthood as loneliness. The signal is clear across different groups and measures, but the evidence base is still small. Larger, well‑designed studies using consistent definitions of adversity are needed to refine who is at greatest risk and which interventions work best.  

Source: Curtis A, Luchetti M, Prendergast C, et al. “Adverse childhood experiences and loneliness: A systematic review and meta‑analysis,” Social Science & Medicine 370 (2025) 117860 (open‑access, preregistered on PROSPERO).  

Editor’s note: This article is for information only and is not a substitute for professional medical advice.