13 sources: 10 meta-analyses, 1 narrative review, 1 other design, 1 systematic review
Social · Concept
Understanding Loneliness and Its Effects on Health
Loneliness, the gap between the connection you want and what you have, is linked to depression and worse mental health.
Beta content: this dimension's review set is version 0.9-beta and upgrades in place after the Round-2 internal reviews.
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Before you start
People in acute distress may find the topic activating
When to seek a professional
- Persistent loneliness or isolation accompanied by low mood, hopelessness, loss of interest, or withdrawal lasting 2+ weeks: encourage contact with a primary care provider or mental health professional
- Thoughts of self-harm or that life is not worth living: direct to crisis line / emergency services immediately
Conceptual, no dose
For most adultsOlder adultsYoung adults
What the evidence says
What the sources say
The association between loneliness and poorer mental health is consistent across many reviews. One honest caveat: loneliness is subjective (a person can feel lonely in a crowd or content alone). Loneliness is a normal human signal, not a diagnosis.
Common misconceptions
- Myth: loneliness means being alone. Reality: it is the felt gap between desired and actual connection.
What we won't claim
- Do not treat loneliness as a clinical condition to be diagnosed or treated
- Do not imply loneliness is a personal failing
13 sources: 10 meta-analyses, 1 narrative review, 1 other design, 1 systematic review
- Agreement
- Direction recorded for 0 of 13 sources; not yet recorded for the rest.
- The claim's outcome
- Outcome not yet recorded
- Certainty
- No source states a certainty rating.
- Authors
- Sources share authors: Zhifei Wen (first author of 2 sources); Brea Perry (senior author of 2 sources); Xiangeng Zhang (senior author of 2 sources).
What each source measured and concluded (13)
meta-analysis · 2025
J et al. (2025) — The relationship between social support and mental health in athletes: a systematic review and meta-analysis.
- What it measured
- Association between social support and mental health outcomes
- How it was read
- screened only, not extracted
- What the review says it includes
- Systematic review and meta-analysis
- Studies and participants, as stated
- 40 studies encompassing 14,462 athletes
meta-analysis · 2023
Bryan et al. (2023) — Loneliness in the workplace: a mixed-method systematic review and meta-analysis
- What it measured
- Workplace, health, and personal factors associated with workplace loneliness
- How it was read
- screened only, not extracted
- What the review says it includes
- Mixed-method systematic review and meta-analysis
- Studies and participants, as stated
- 49 articles
meta-analysis · 2022
Lee et al. (2022) — Effectiveness of Social Support for Community-Dwelling Elderly with Depression: A Systematic Review and Meta-Analysis
- What it measured
- Depression
- How it was read
- screened only, not extracted
- What the review says it includes
- Systematic review and meta-analysis
- Studies and participants, as stated
- 52 studies (of 3449 screened)
meta-analysis · 2024
Wen et al. (2024) — Mediating effect of social support and resilience between loneliness and depression in older adults: A systematic review and meta-analytic structural equation modeling.
- What it measured
- Mediating role of social support and resilience between loneliness and depression
- How it was read
- screened only, not extracted
- What the review says it includes
- Systematic review and meta-analytic structural equation modeling (MASEM)
- Studies and participants, as stated
- 53 studies; 40,929 older adults
meta-analysis · 2022
Wen et al. (2022) — Factors Associated With Social Isolation in Older Adults: A Systematic Review and Meta-Analysis.
- What it measured
- Factors associated with social isolation
- How it was read
- screened only, not extracted
meta-analysis · 2022
Mann et al. (2022) — Loneliness and the onset of new mental health problems in the general population
- What it measured
- Relationship between loneliness and new onset of mental health problems
- How it was read
- screened only, not extracted
- What the review says it includes
- Systematic review and meta-analysis of longitudinal studies (with narrative synthesis)
- Studies and participants, as stated
- 32 studies (8 cohorts in meta-analysis)
meta-analysis · 2024
S et al. (2024) — A Systematic Review and Meta-Analysis of the Association Between Physical Capability, Social Support, Loneliness, Depression, Anxiety, and Life Satisfaction in Older Adults.
- What it measured
- Association of physical capability, social support, loneliness, depression, anxiety with life satisfaction
- How it was read
- screened only, not extracted
- What the review says it includes
- Systematic review and meta-analysis of observational studies
- Studies and participants, as stated
- 78 studies (57 in meta-analysis); 164,478 participants
meta-analysis · 2020
Henssler et al. (2020) — Mental health effects of infection containment strategies: quarantine and isolation—a systematic review and meta-analysis
- What it measured
- Depression, anxiety, and stress-related disorders
- How it was read
- screened only, not extracted
- What the review says it includes
- Systematic review and meta-analysis (random-effects)
- Studies and participants, as stated
- 25 studies (6807 screened)
meta-analysis · 2020
Park et al. (2020) — The Effect of Loneliness on Distinct Health Outcomes: A Comprehensive Review and Meta-Analysis.
- What it measured
- Distinct health outcomes (mental, general, well-being, physical, sleep, cognition)
- How it was read
- screened only, not extracted
- What the review says it includes
- Systematic review and meta-analysis
- Studies and participants, as stated
- 114 studies
other design · 2025
Dodge et al. (2025) — Social Connection and Brain Function: From Measurement to Clinical Trials
- What it measured
- Social connection measurement and links to brain/cognitive health
- How it was read
- screened only, not extracted
narrative review · 2026
DeAngelis et al. (2026) — Social connection and cognitive health: A review of concepts, measures, and research priorities
- What it measured
- Conceptual model and measures linking social connection to cognitive health
- How it was read
- screened only, not extracted
systematic review · 2023
Joshi et al. (2023) — Social connections as determinants of cognitive health and as targets for social interventions in persons with or at risk of Alzheimer’s disease and related disorders: a scoping review
- What it measured
- Association of social connections with cognitive decline and effect of social interventions
- How it was read
- screened only, not extracted
- What the review says it includes
- Scoping review of meta-analyses and systematic reviews
- Studies and participants, as stated
- 11 meta-analyses/systematic reviews (social connections and cognitive decline) plus 8 systematic reviews of interventions
meta-analysis · 2026
Genecov et al. (2026) — A systematic review and meta-analysis finds that psychological well-being predicts all-cause mortality independently of psychological ill-being
- What it measured
- All-cause mortality
- How it was read
- screened only, not extracted
- What the review says it includes
- Systematic review and random-effects meta-analysis of prospective longitudinal studies
- Studies and participants, as stated
- 99 prospective longitudinal studies
- Heterogeneity, as stated
- Well-being predicted lower mortality when controlling for ill-being (HR 0.86, 95% CI 0.84-0.88); consistent across constructs; highly heterogeneous (I2~0.75)
Key sources (13)
Every source below is shown with its study design and links to the original study. This is the audit trail.
meta-analysisThe relationship between social support and mental health in athletes: a systematic review and meta-analysis.
meta-analysisLoneliness in the workplace: a mixed-method systematic review and meta-analysis
meta-analysisEffectiveness of Social Support for Community-Dwelling Elderly with Depression: A Systematic Review and Meta-Analysis
meta-analysisMediating effect of social support and resilience between loneliness and depression in older adults: A systematic review and meta-analytic structural equation modeling.
meta-analysisFactors Associated With Social Isolation in Older Adults: A Systematic Review and Meta-Analysis.
meta-analysisLoneliness and the onset of new mental health problems in the general population
meta-analysisA Systematic Review and Meta-Analysis of the Association Between Physical Capability, Social Support, Loneliness, Depression, Anxiety, and Life Satisfaction in Older Adults.
meta-analysisMental health effects of infection containment strategies: quarantine and isolation—a systematic review and meta-analysis
meta-analysisThe Effect of Loneliness on Distinct Health Outcomes: A Comprehensive Review and Meta-Analysis.
other designSocial Connection and Brain Function: From Measurement to Clinical Trials
narrative reviewSocial connection and cognitive health: A review of concepts, measures, and research priorities
systematic reviewSocial connections as determinants of cognitive health and as targets for social interventions in persons with or at risk of Alzheimer’s disease and related disorders: a scoping review
meta-analysisA systematic review and meta-analysis finds that psychological well-being predicts all-cause mortality independently of psychological ill-being
Explore all 367 studies in Social →
The full evidence base this focus area draws on, every study with its design and DOI.What it is for
Feel less lonelyUnderstand myself better