Why Lonely, Single People May Die of Depression, Cardiovascular Diseases – Doctors Warn

Health professionals have issued strong warnings that prolonged loneliness, especially among people who live alone or remain socially isolated, is increasingly linked to fatal health conditions, including cardiovascular diseases, depression, weakened immunity, and premature death.

Experts who spoke with PUNCH Healthwise said loneliness triggers excessive production of stress hormones like cortisol, which in turn elevate heart rate, blood pressure, and blood sugar levels, critical factors for diseases such as stroke, hypertension, type 2 diabetes, and heart attacks.

A recent report by the World Health Organisation (WHO) highlights the global scale of the crisis. According to the report, no fewer than 871,000 people die annually due to loneliness-related complications, and one in six people globally is affected by loneliness or social isolation. The WHO also revealed that one in three older people and one in four adolescents are currently estimated to be socially isolated.

“Loneliness is not just an emotional burden. It is now a global public health concern,” the report noted.

Physicians say loneliness doesn’t just affect mental health; it significantly compromises physical well-being as well. Those who are socially isolated reportedly suffer from a 30% higher risk of early mortality.

Professor Tanimola Akande, a public health expert at the University of Ilorin, explained that isolation leads to inactivity, poor mental stimulation, and weakened metabolic functions.

“Loneliness means such a person stays long without interacting with other people, and this gives room for inactivity, little or no social engagements, and diseases that particularly affect the mental and physical health of such individuals,” he said.

According to him, a lonely person tends to burn fewer calories, becomes sedentary, and often overeats, setting the stage for obesity, diabetes, and cardiovascular problems.

“The lack of social engagement often leads to depression, anxiety, drug addiction, suicidal tendencies, and even dementia,” Prof. Akande warned.

Echoing similar concerns, Dr. Timothy Olusegun, another public health physician, warned that people who live alone or feel chronically lonely tend to release more cortisol. When this stress hormone floods the body for too long, it causes inflammation, which increases the risk of cardiovascular illnesses.

“This is a serious health concern because loneliness affects every aspect of health and well-being,” he said.

“People who are lonely tend to eat more, exercise less, sleep poorly, and adopt other unhealthy behaviours that increase their risk of early death.”

Dr. Olusegun also pointed out that loneliness has been shown to weaken the immune system, making people more vulnerable to infections and chronic illnesses.

Loneliness has also been linked to neurodegenerative disorders. Studies show that adults who are chronically lonely are 40% more likely to develop dementia or Alzheimer’s disease.

“Chronic inflammation caused by social isolation contributes to cognitive decline,” Dr. Olusegun said.

“And inflammation is often the result of cortisol overload, poor lifestyle choices, and lack of physical and emotional support.”
Global Research Confirms the Risks

A study published in the Proceedings of the National Academy of Sciences found that loneliness alters gene expression in the immune system, which increases vulnerability to disease. The study, which tracked 141 adults over time, found that lonely individuals showed elevated expression of the CTRA gene, which promotes inflammation and reduces antiviral immunity.

The researchers, led by psychology professor John Cacioppo of the University of Chicago, discovered that loneliness and immune dysfunction often reinforce each other. This same pattern was confirmed in rhesus macaque monkeys at the California National Primate Research Centre, which also showed heightened stress and weakened immunity linked to isolation.

WHO’s report also warned that teenagers and adolescents are not spared from the dangers of loneliness. According to the organisation, lonely teenagers are 22% more likely to perform poorly academically and struggle with long-term emotional and psychological stability.

Adults facing loneliness were also found to have difficulty finding or retaining employment, further deepening social isolation and poor health outcomes.

Experts argue that addressing loneliness goes beyond prescribing antidepressants or heart medications. What is needed, they say, is the creation of inclusive, supportive, face-to-face social spaces—especially in urban centres.

“We need to prioritise community engagement and mental wellness as part of our public health strategy,” Prof. Akande advised.
Loneliness, a Silent Killer

In many cases, people suffering from loneliness do not present typical medical symptoms until their condition deteriorates severely. Experts call this the “silent progression” of chronic illnesses linked to isolation.

“People don’t realise that mental and emotional wellbeing are just as important as diet or exercise,” Dr. Olusegun added.
“If we don’t take loneliness seriously, we will keep seeing avoidable deaths.”
Final Word

As Nigeria and other nations grapple with the increasing burden of non-communicable diseases, physicians are urging individuals, communities, and governments to begin treating loneliness as a health risk factor, just like high blood pressure or smoking.

They recommend promoting strong community ties and peer support groups, encouraging family connections, especially for older adults, Integrating social support into healthcare for single or elderly patients
National campaigns to destigmatise talking about isolation and depression

“Loneliness may not show on the body, but it eats deep into the heart, the brain, and the immune system,” Prof. Akande concluded.