The WHO never issued a formal “epidemic” declaration. It now treats loneliness as a global public health priority, putting a lack of social connection alongside threats to physical and mental health.1World Health Organization. Report of the WHO Commission on Social Connection The reason is that long-lasting loneliness is linked to serious illness and earlier death, not just unhappiness.2World Health Organization. Report of the WHO Commission on Social Connection The word “epidemic” mostly came from headlines and from the US Surgeon General’s 2023 advisory, while WHO’s own step was to build a global response. The problem reaches every age and every country, and it is often worst among young adults rather than only the elderly.
What WHO Actually Did About Loneliness
In November 2023, WHO set up a Commission on Social Connection to run for three years.3World Health Organization. WHO Commission on Social Connection Its aim is for loneliness to be recognised and funded as a global public health priority.4World Health Organization. WHO Commission on Social Connection The commission’s report found that isolation and loneliness are widespread, with serious but under-recognised effects on health and society.5World Health Organization. Report of the WHO Commission on Social Connection WHO has estimated that roughly 1 in 6 people worldwide feel lonely. The report asks governments, researchers and every sector to treat social health with the same urgency as physical and mental health.6World Health Organization. Report of the WHO Commission on Social Connection
“Epidemic” usually describes a spreading infection, so using it here is a metaphor for something very common and harmful. WHO’s own language centres on “priority” and “social health” rather than an emergency declaration.
A WHO commission is a group of outside experts and officials brought together to study a problem and recommend action. It is not a law or a treaty. Its power lies in agenda-setting: when WHO names a topic, health ministries and funders are more likely to measure it and budget for it.
Two different problems sit under the one word. Social isolation means having few relationships or little contact. Loneliness is the painful feeling that your connections fall short of what you want. So a person can live alone and feel fine, or be surrounded by people and feel lonely.
To tell which one you’re dealing with, ask whether the trouble is how often you see people or how those contacts feel. Few contacts but contentment points to isolation that may not hurt you much. Plenty of contacts but a feeling of being unseen points to loneliness, which needs closer relationships rather than more of them.
How Loneliness Harms Health
People who are socially isolated are about 29% more likely to die over the study period, lonely people about 26%, and people living alone about 32%, even after other factors are accounted for.7PubMed. Loneliness and social isolation as risk factors for mortality: a meta-analytic review A larger pooled analysis of 90 studies found isolation raised the risk of death from any cause by about a third and loneliness by about 14%.8PubMed. A systematic review and meta-analysis of 90 cohort studies of social isolation, loneliness and mortality Isolation was also linked to about a 24% higher risk of dying from cancer.9PubMed. A systematic review and meta-analysis of 90 cohort studies of social isolation, loneliness and mortality
The heart and brain show similar patterns. Lonely or isolated people have about a 29% higher risk of developing heart disease and about a 32% higher risk of stroke.10PubMed Central. Loneliness and social isolation as risk factors for coronary heart disease and stroke: systematic review and meta-analysis of longitudinal observational studies In older adults followed over years, loneliness raised heart risk even after smoking, blood pressure and other usual risk factors were considered.11PubMed. Loneliness, social isolation and risk of cardiovascular disease in the English Longitudinal Study of Ageing Feeling lonely raises the risk of dementia by about 31%,12Nature Mental Health. Loneliness linked to dementia risk in large-scale analysis and it is linked to faster decline in memory and thinking over time.13PubMed Central. The Impact of Loneliness and Social Isolation on Cognitive Aging: A Narrative Review
Mental health takes a hit too. In the general population, loneliness nearly doubles the likelihood of depression.14PubMed Central. Loneliness in the general population: prevalence, determinants and relations to mental health It is also tied to more anxiety and a higher chance of suicidal thoughts.15PubMed Central. Loneliness in the general population: prevalence, determinants and relations to mental health Anyone feeling persistently lonely and low should mention both to a doctor.
These percentages are relative risks. They compare one group’s chance of an outcome with another group’s chance, so “about 29%” does not mean a 29% chance. A relative rise increases whatever your starting risk is. For a healthy 30-year-old the extra risk in absolute terms is small, while for an older person with heart disease the same increase matters much more.
The figures come from following large groups for years and comparing who got ill, so they show links, not proof of cause. Researchers adjust for age, smoking and existing illness, and the links persist, which is why health agencies take them seriously.
The arrow also points both ways. Illness and depression can make people withdraw, so some loneliness is a result of poor health. But studies that follow people forward in time show loneliness also comes before new heart disease and dementia.
What Loneliness Does Inside the Body
Loneliness may work like hunger or pain: an unpleasant signal that pushes us to fix a problem.16PubMed Central. Loneliness Across Phylogeny and a Call for Comparative Studies and Animal Models For social animals, being with a group meant safety and survival.17Quanta Magazine. New Evidence for the Necessity of Loneliness A short bout of loneliness is normal and useful. The harm comes when the alarm never switches off.
In lonely people, white blood cells seem more active in ways that raise inflammation.18NPR. Loneliness May Warp Our Genes, And Our Immune Systems But they appear to make less of the body’s antiviral defences.19NPR. Loneliness May Warp Our Genes, And Our Immune Systems Their bodies also seem to become less responsive to cortisol, a stress hormone that normally calms inflammation.20NPR. Loneliness May Warp Our Genes, And Our Immune Systems People who are often lonely tend to have a flatter daily cortisol pattern, without the usual morning high and evening drop.21PubMed Central. Loneliness and Cortisol: Momentary, Day-to-day, and Trait Associations In healthy older adults, loneliness was linked to higher cortisol at bedtime.22PubMed. The relationship between loneliness and cognition in healthy older men and women: The role of cortisol Ongoing inflammation and stress hormones are known contributors to heart disease and brain ageing, which may help explain the risks above. Lonely people often become more watchful for rejection, which makes reaching out feel harder.
The evening matters because cortisol should fall by bedtime so the body can rest and repair. When it stays high, sleep and recovery suffer. Calm evening contact, like a call with a friend, is one practical way to break that pattern. The body changes described here are linked to persistent loneliness, not occasional lonely moments.
Who Is Most Likely to Be Lonely
Across eight countries, nearly 4 in 10 adults said they felt lonely.23The Source. Nearly half of young adults report loneliness in eight-country study Among 18- to 24-year-olds it was nearly 1 in 2, compared with about 30% of those 55 and older.24The Source. Nearly half of young adults report loneliness in eight-country study About 40% of US teenagers report at least some loneliness, and about 9% say they are often lonely.25PubMed Central. Adolescent loneliness in the United States: Prevalence, sociodemographic correlates, and psychological health over time
Old age is not the peak of reported loneliness, though older people can still be severely affected. Early adulthood brings moves for school or work that break old friendships. Expectations of a busy social life can make ordinary quiet stretches feel like failure. Older adults often have long-standing ties and lower expectations of constant company.
In later life, loneliness is most consistently linked to not having a partner or losing one, a small social circle, little social activity, poor health, and depression.26PubMed. A systematic review of longitudinal risk factors for loneliness in older adults Big transitions like widowhood, retirement or illness are times to watch for it.
In a parent or friend, signs worth noticing include fewer mentions of friends or plans, and losing interest in activities they used to enjoy. More doctor visits or complaints of feeling unwell can also be a clue, as can a recent loss, move or retirement.
Most research comes from wealthy countries.27PubMed. Experiences of loneliness in lower- and middle-income countries: A systematic review of qualitative studies In lower-income countries, poverty and stigma often stand in the way of the relationships people expect.28PubMed. Experiences of loneliness in lower- and middle-income countries: A systematic review of qualitative studies What counts as lonely also varies by culture, so solutions have to fit local life.29PubMed. Experiences of loneliness in lower- and middle-income countries: A systematic review of qualitative studies
What in Modern Life Feeds Loneliness
Both scrolling and actively posting on social media were linked to rising loneliness over time.30Baylor University. Social Media’s Double-Edged Sword: Study Links Both Active and Passive Use to Rising Loneliness Online interaction may not meet the needs that face-to-face contact does.31Baylor University. Social Media’s Double-Edged Sword: Study Links Both Active and Passive Use to Rising Loneliness Being reachable at any moment is different from being known by someone, and the feeling of loneliness tracks the second. Online contact often skips the cues of tone, touch and shared time that make company satisfying, and scrolling can invite comparison with other people’s apparent social lives.
To use your phone without making things worse, use apps to set up in-person plans rather than replace them. Notice whether a scrolling session leaves you feeling more left out. A voice or video call with one person usually beats broadcasting to many.
Where we live matters too. Green space, parks, community gardens and open areas are linked to better social health.32Social Connection Guidelines. How the built environment shapes loneliness Libraries, cafes, clubs and other easy-to-enter spaces help people connect, but people need walkable streets and affordable transport to reach them.33Social Connection Guidelines. How the built environment shapes loneliness Front porches can encourage chats with neighbours more than backyards do.34PubMed Central. How Built Environment Characteristics Influence Social Interactions During Neighbourhood Walks Among Urban Inhabitants Friendly encounters on neighbourhood walks make people feel safer.35PubMed Central. How Built Environment Characteristics Influence Social Interactions During Neighbourhood Walks Among Urban Inhabitants
Walk the same route at the same time to become a familiar face. Sit out front rather than out back when weather allows. Make the library, a cafe or a park a regular stop.
What Actually Helps With Loneliness
People who joined more groups felt a stronger sense of belonging, which in turn lowered loneliness.36PubMed Central. The social cure of social prescribing: a mixed-methods study on the benefits of social connectedness on quality and effectiveness of care provision Adding contacts that feel shallow may not change loneliness. Regular contact with the same people around something shared lets a sense of being part of something grow. That is why joining one group you keep attending tends to do more than meeting many people once.
In some countries, doctors can refer patients to a service known as social prescribing, which connects them to local clubs, volunteering or classes. A doctor or link worker talks with you about what matters to you, not just what is wrong with you. They then point you to something local that fits, such as a walking group, a gardening project or a class, and may check in afterwards. Patients in one English program reported less anxiety and better wellbeing and daily functioning than those with usual care.37Center for Health Care Strategies. Reducing Social Isolation and Loneliness Among Older Adults Through Social Prescribing In one scheme, 66% of participants went to their GP less often,38Campaign to End Loneliness. Social prescribing offers connection for loneliness though its long-term effects still need more study.39Campaign to End Loneliness. Social prescribing offers connection for loneliness Ask your doctor or a local council whether such services exist where you live.
Cognitive behavioural therapy, a talking therapy that works on unhelpful thoughts, reduced loneliness substantially in older adults, though study quality was low and results varied widely.40PubMed. The effectiveness of cognitive behavioral therapy on loneliness among older adults: A systematic review and meta-analysis A small early trial of a version for young people with chronic loneliness found scores fell by about two thirds.41Behavioural and Cognitive Psychotherapy. The development and preliminary evaluation of Cognitive Behavioural Therapy (CBT) for Chronic Loneliness in Young People It works on a social problem because long loneliness trains the mind to expect rejection. That expectation leads people to hold back, which confirms the fear. Therapy helps test those predictions and practise small steps of contact. If loneliness persists despite efforts to connect, a therapist is a reasonable next step.
A first week of reconnecting could look like this: message or call one person you’ve lost touch with, and pick one recurring activity, such as a class or volunteering, so you see the same faces. Expect early awkwardness, since belonging builds with repetition, not a single visit. If a relative is lonely, check in on a set day each week.
Why Governments Treat Loneliness as Their Problem
Loneliness and isolation are estimated to cost between US$2 billion and US$25.2 billion a year in the economies studied, mostly through health care and lost productivity.42PubMed Central. An Updated Systematic Literature Review of the Economic Costs of Loneliness and Social Isolation and the Cost Effectiveness of Interventions Those figures leave out long-term care, even though loneliness is a risk for moving into a care home.43McKnight’s Senior Living. Loneliness and social isolation can cost society more than $25 billion annually
Some programs appear to pay back. A social prescribing pilot in Wales saved about £78 per patient through fewer appointments and prescriptions.44Center for Health Care Strategies. Reducing Social Isolation and Loneliness Among Older Adults Through Social Prescribing The UK launched a national loneliness strategy in 2018 and reports on it every year.45GOV.UK. Joint message from the UK and Japanese Loneliness Ministers Japan has appointed a minister for loneliness and isolation.46GOV.UK. Joint message from the UK and Japanese Loneliness Ministers
Locally, public action can mean funding community spaces like libraries and parks, training doctors to ask about loneliness, and providing transport that lets older and disabled people get out. These changes help people who would never seek help themselves.