Global trends in healthy life expectancy

Research indicates that while global life expectancy has increased since 1990, the number of years lived in good health has not kept pace. On average, people globally spend 10.7 years living with health limitations, an increase of roughly two years since 1990. Major contributors to this trend include depression, hearing loss, and back pain.

Specific studies from Tulane University highlight that loneliness and social isolation significantly reduce healthy life expectancy. Analyzing data from over 277,000 adults, researchers found that women lose approximately 2.4 years of healthy physical life and 3.7 years of mental health due to these factors, while men lose 1.7 years of physical health and 5.8 years of mental health. The research distinguishes between social isolation, defined as limited social interaction, and loneliness, which is the subjective dissatisfaction with relationship quality. Both are linked to higher risks of cognitive decline, diabetes, and cardiovascular disease.

Recent findings suggest that chronic loneliness and social isolation are significant public health concerns that could potentially reduce healthy life expectancy by nearly six years. In the United States, approximately half of adults experience loneliness, with a similar percentage facing social isolation.

Biological impacts include a continuous state of physiological alert that can dysregulate cortisol production, trigger systemic inflammation, and weaken the immune system, increasing risks for cardiovascular and metabolic diseases. Behavioral consequences also contribute, as isolated individuals may experience chronic insomnia, decreased physical activity, poor dietary habits, and reduced engagement with medical self-care.