Loneliness: a silent threat to brain and body

Author: Anouk Geraets, Laure Pauly | Editor: Anja Leist

Did you know that loneliness can increase the risk of premature death as much as smoking 15 cigarettes a day? In fact, its mortality rate may be higher than obesity or physical inactivity¹. Recognizing loneliness as a public health concern has led to policy initiatives at national, European and international levels.

Alone vs. Lonely: What’s the difference?

You can have a partner, children, and an extensive social circle and still feel lonely. Conversely, someone with few social connections may not feel lonely at all. Loneliness is not the same as being alone. Although loneliness is associated with social isolation, the two terms are not substitutable. Isolation is a measurable objective state, determined by the number of social contacts a person has. While different definitions of loneliness exist, it is most commonly defined as a negative subjective experience of lacking meaningful social connections.

The loneliness epidemic – a widespread issue across all ages

The term “loneliness epidemic” refers to the widespread and increasing experience of loneliness and social isolation across populations, recognized as a major public health concern due to its serious impact on physical, mental, and cognitive health. Rapid demographic changes, digitalization, and evolving family structures have intensified isolation across the world. Technology has undoubtedly enhanced communication on a global scale. However, it has also altered the nature of interpersonal relationships. We must ensure technology strengthens and not weakens human connection. Many increasing concerns related to loneliness are about communication technology in which online social connections can not replace physical social connections. In addition, the increase in one-person households means that many people do not benefit from the traditional support networks that often come from living with other people.

Who Feels Lonely? Insights from the EU

Social isolation and loneliness affect people of all regions and ages. A recent report from the World Health Organization (WHO) revealed that 1 in 6 people worldwide is affected by loneliness, with adolescents and young adults disproportionately affected. The first EU-wide survey on loneliness (EU-LS 2022) reported even higher numbers: 13% of respondents felt lonely most or all of the time in the past four weeks and 35% felt lonely at least at one time in their life. According to this EU-wide survey, Luxembourg is the second loneliest country in the EU, with 17% of the respondents reporting to feel lonely most or all of the time. These numbers highlight the growing need to address loneliness as a public health issue.

Can loneliness make us sick? 

Yes, loneliness can have a serious impact on our physical and mental health, and the well-being of our communities and society. According to the WHO, loneliness is linked to an estimated 100 deaths every hour, more than 871,000 deaths annually. Strong social connections can lead to better health and longer life. The list of health conditions linked to loneliness is surprisingly long. Some connections are intuitive, individuals who are lonely often experience depression or anxiety. But other links are less expected: research shows that loneliness is associated with a higher risk of high blood pressure, immune system dysfunction, and even dementia ^{2,3,4, 5,6, 7}. These findings highlight that loneliness is not just an emotional experience, it’s a serious health risk with wide-ranging effects on both body and brain. If you would like to understand HOW loneliness and social isolation affect the brain, read our follow-up post: How Social Isolation Reshapes the Brain – A Dive into the Neuroscience of Connection.

What Can We Do About Loneliness?

1. Remain socially connected. Some remedies for loneliness will come as no surprise. Join a local club, volunteer, invite people for a drink, or visit events.
   
2. Remain physically active. One study found that walking for one hour reversed feelings of low mood associated with loneliness in some people⁸.
   
3. Try to make your time alone enjoyable and meaningful. Study demonstrates that people with negative beliefs about being alone experience a steep increase in loneliness after spending time alone in daily life, whereas those with positive beliefs feel less lonely after spending time alone⁹.

All in all… Loneliness is more than a fleeting feeling, it’s a silent threat to our (brain) health. But it’s also a modifiable one. By recognizing loneliness as a serious public health issue, we can begin to dismantle the stigma around it and take meaningful steps toward prevention and intervention. Whether through policy, community initiatives, or individual actions, fostering genuine human connection must become a collective priority.

The antidote to loneliness isn’t just being around people, it’s feeling seen, heard, and valued. Let’s build a society where human connection is nurtured, where reaching out is a sign of strength, and where no one feels invisible. You can do your part and make a difference already with small gestures: reach out with a nice word to your neighbor or nod a ‘hello’ at the bus stop.  Taking initiative to build deeper, meaningful connections for you and your social circle will ultimately lead to living longer, healthier lives.

If you would like to understand HOW loneliness and social isolation affect the brain, read our follow-up post: How Social Isolation Reshapes the Brain – A Dive into the Neuroscience of Connection.

Feeling lonely, need help, or know someone who does? Please find support through these local services in Luxembourg:

Helplines and Crisis Support

• SOS Détresse – Emotional support via phone
• Kanner-Jugendtelefon (KJT) – For children, youth, and parents
• Fraëntelefon – Support for women in distress
• Elterentelefon – Listening service for parents
• Luxembourg Alzheimer Association (ALA)

Mental Health Services and Therapy

• Réseau Psy – Psychological support centers
• Ligue Santé Mentale – Mental health consultations and prevention
• Stressberodung – Stress counseling
• GesondheetsZentrum Zitha – Health and wellness center

The authors of this post are ambassadors of the LONELY-EU project in Luxembourg, part of Europe’s first coordinated network dedicated to understanding and reducing loneliness. LONELY-EU brings together researchers, policymakers, practitioners, and people with lived experience to share knowledge and develop long-term strategies for a more connected Europe. If you care about connection and want to be part of this growing movement, we invite you to join us.

👉 Learn more and get involved: https://lonelinessineurope.eu

📧 Contact us: anouk.geraets@uni.lu  | laure.pauly@uni.lu

🔗 Follow us on LinkedIn: LONELY-EU

For better readability of the text, the assistance of Microsoft Copilot, an AI language model based on the GPT-4 architecture, secured with UL enterprise data protection, has been used.

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