Happiness
Self-Rated Happiness and Mortality Risk: Quantifying the Longevity Benefits of Subjective Well-Being
Recent longitudinal research has revealed compelling associations between subjective well-being—including happiness and life satisfaction—and reduced mortality risk. This report synthesizes current evidence on how self-rated happiness levels impact longevity, examining both the magnitude of effect and factors that modify this relationship.
Life Expectancy Benefits Associated with Happiness
Multiple large-scale studies demonstrate that high levels of self-reported happiness and life satisfaction are associated with substantial longevity benefits, though the magnitude varies across populations.
Quantifiable Years of Life Extension
A comprehensive analysis of the National Health Interview Survey (NHIS) linked to 14 years of mortality data revealed striking differences in life expectancy based on happiness levels. At age 18, adults reporting high levels of happiness had a 7.5-year greater life expectancy compared to those with low happiness levels. The gap was even larger for life satisfaction, with highly satisfied individuals living 8.9 years longer than those who were dissatisfied1.
These life expectancy advantages persisted across the lifespan. At age 45, individuals with low happiness had 6.4 fewer years of life expectancy than their happy counterparts, while at age 65, the difference was still a substantial 3.7 years1. These findings indicate that happiness advantages accumulate throughout life but may diminish somewhat at more advanced ages.
The English Longitudinal Study of Ageing similarly found that individuals with high affective well-being lived significantly longer. A 50-year-old woman with high well-being could expect to live approximately 6 years longer than a woman of similar age with low well-being2.
Gender Differences in Longevity Benefits
The relationship between happiness and longevity demonstrates notable gender differences. The impact of happiness on life expectancy appears greater for women than men, particularly at older ages. At age 45, women with low happiness had 7 years shorter life expectancy than their happy counterparts, while men with low happiness had 6 years shorter life expectancy than happy men1.
Conversely, life satisfaction had a stronger impact on men's longevity. Men with low life satisfaction had 10 years shorter life expectancy compared to highly satisfied men, whereas women with low satisfaction had 8 years shorter life expectancy than highly satisfied women1.
A Finnish cohort study examining life satisfaction found significant mortality effects in men but not women. Among men, dissatisfaction was linearly associated with increased mortality, with age-adjusted hazard ratios of 2.11 for all-cause mortality in dissatisfied versus satisfied men3.
Mortality Risk Associated with Happiness Levels
Multiple studies have quantified the mortality risk associated with different levels of happiness and life satisfaction.
All-Cause Mortality Risk
The NHIS study found that adults reporting little or no happiness had an 82% higher risk of all-cause mortality (HR=1.82; 95% CI=1.59,2.08) compared to those reporting happiness all of the time, after controlling for age. When additionally controlling for sociodemographic, behavioral, and health characteristics, the mortality risk remained 36% higher (HR=1.36; 95% CI=1.17,1.57) in adults with little/no happiness1.
For life satisfaction, the contrast was even more pronounced. Mortality risk was 107% higher (HR=2.07; 95% CI=1.80,2.38) in adults who were very dissatisfied with their life after controlling for age, and remained 39% higher (HR=1.39; 95% CI=1.20,1.60) after controlling for all covariates1.
A meta-analysis of 62 studies published up to 2016 reported a pooled mortality hazard ratio of 0.920 (95% CI, 0.905-0.934) for individuals reporting high versus lower subjective well-being, indicating an approximately 8% reduction in mortality risk associated with higher well-being2.
Quality of Life and Health-Related Benefits
The longevity advantages of happiness extend beyond simply living longer to include more years of healthy, disability-free life.
Disease-Free and Disability-Free Years
The English Longitudinal Study of Ageing found that happiness was associated with both longer life and healthier years. A 50-year-old woman with high well-being could expect 31.4 years (95% CI, 30.5-31.9) free of disability, compared with only 20.8 years (95% CI, 20.1-22.1) for a woman with low well-being—representing an additional 10.6 years of disability-free life2.
Similarly, a 50-year-old man with high affective well-being could expect to live 20.8 years (95% CI, 18.7-22.4) without chronic disease, compared with just 11.4 years (95% CI, 8.5-14.6) for a man reporting low well-being—an additional 9.4 years free from chronic disease2.
These findings suggest that happiness and life satisfaction not only extend life but also compress morbidity, resulting in a greater proportion of life spent in good health.
Factors Modifying the Happiness-Mortality Relationship
Several factors influence the relationship between happiness and mortality, potentially explaining some inconsistencies across studies.
Self-Rated Health as a Mediator
Evidence suggests that physical health status may partially mediate the relationship between happiness and mortality. A representative sample of US adults found that the association between well-being and mortality was strongly attenuated by self-rated health. Age-adjusted unhappiness was associated with mortality (HR 1.27; 95% CI 1.11 to 1.45), but this association largely disappeared after adjusting for self-rated health (HR 1.01; 95% CI 0.88 to 1.16)4.
A German study found that poor self-rated physical health, but not mental health, was predictive of mortality when adjusting for objective risk factors. The meta-analysis by DeSalvo reported a two-fold higher mortality risk for persons with poor compared to excellent self-rated health5.
Socioeconomic and Behavioral Factors
Socioeconomic status and health behaviors also modify the relationship between happiness and mortality. In the Finnish Twin Cohort study, adjusting for marital status, social class, smoking, alcohol use, and physical activity reduced the mortality risks associated with dissatisfaction from 2.11 to 1.49 in men3.
Unhappy individuals who engage in poor health behaviors face compounded risks. Dissatisfaction was particularly associated with increased disease mortality in men with heavy alcohol use (HR = 3.76, 95% CI: 1.61, 8.80)3.
Conclusion
The evidence strongly supports a relationship between self-rated happiness/life satisfaction and reduced mortality risk, with substantial longevity benefits for happier individuals. People reporting high levels of subjective well-being live approximately 6-9 years longer than those with low well-being, with benefits persisting across age groups but varying by gender.
The mortality risk associated with unhappiness or dissatisfaction ranges from 36-107% higher depending on the specific measure and covariates included. These effects are partially mediated by self-rated health and health behaviors but remain significant in most comprehensive analyses.
Beyond simply extending life, happiness appears to improve health-related quality of life, with individuals reporting high well-being gaining approximately 9-11 additional years of disability-free and disease-free life compared to those with low well-being.
These findings highlight the importance of psychological well-being as a public health priority and suggest that interventions to enhance happiness and life satisfaction could potentially extend both lifespan and healthspan.