A new study highlights the significant role mental wellbeing plays in determining healthy aging, regardless of socioeconomic status. By analyzing genetic data from over 2.3 million Europeans, researchers found that better mental wellbeing leads to healthier aging, characterized by greater resilience, improved self-rated health, and longevity. Interestingly, they also identified certain lifestyle choices, including being active, not smoking, and eating cheese and fruit, as beneficial to mental wellbeing and healthy aging.
The findings have been published in Nature Human Behaviour.
Human life expectancy has increased significantly over recent decades, posing challenges for individuals and society, such as healthcare demands and financial burdens. While physical health and longevity have often been the focus of aging research, the role of mental wellbeing has received less attention. This study aimed to explore the causal relationship between mental wellbeing and healthy aging, and whether this relationship is independent of socioeconomic status.
The study employed a technique known as Mendelian randomization to investigate the causal relationship between mental wellbeing and healthy aging. This method uses genetic data to determine whether an observed association between two traits is causal or merely correlational. By using genetic variants as proxies for exposures, Mendelian randomization helps mitigate biases commonly found in observational studies, such as confounding factors and reverse causality.
The researchers analyzed data from eight genetic datasets encompassing over 2.3 million individuals of European descent. These datasets included information on five key mental wellbeing traits: overall wellbeing, life satisfaction, positive affect, neuroticism, and depressive symptoms. In addition to mental wellbeing, the study considered three socioeconomic indicators: income, education, and occupation.
The study was conducted in two phases. In the first phase, the researchers assessed the causal associations between mental wellbeing traits and various aging phenotypes, which included resilience, self-rated health, healthspan, parental lifespan, and longevity. They also examined whether these associations were independent of socioeconomic status.
In the second phase, they investigated potential mediating factors that could influence the relationship between mental wellbeing and healthy aging. These factors included lifestyle choices (e.g., diet, physical activity, smoking), behaviors (e.g., medication use, cognitive performance), physical functions (e.g., body mass index, cholesterol levels), and diseases (e.g., cardiovascular diseases, diabetes).
The study found a strong causal relationship between better mental wellbeing and healthier aging outcomes. Specifically, individuals with higher levels of mental wellbeing exhibited significantly higher scores on the aging-related genetic influence phenotypes (aging-GIP), as well as greater resilience, improved self-rated health, longer healthspan, and extended parental lifespan.
For example, the study revealed that a genetically determined increase in overall wellbeing was associated with a substantial rise in aging-GIP (1.21 standard deviations), resilience (1.11 standard deviations), self-rated health (0.84 points), healthspan (1.35 odds ratio), and parental lifespan (3.35 years). However, no significant association was found between overall wellbeing and longevity (odds ratio of 1.56).
Importantly, the study demonstrated that the relationship between mental wellbeing and healthy aging persisted regardless of socioeconomic status. While higher income, education, and occupational attainment were each associated with better mental wellbeing, the positive impact of mental wellbeing on aging outcomes remained significant even after adjusting for these socioeconomic factors. This suggests that mental wellbeing exerts a robust and independent influence on healthy aging.
The researchers also identified several lifestyle factors that contribute to mental wellbeing and, consequently, to healthy aging. Among these, being physically active and avoiding smoking were linked to improved mental wellbeing and healthier aging outcomes. Other influential factors included cognitive performance, age at smoking initiation, and the use of certain medications, which also mediated the relationship between mental wellbeing and aging. Additionally, dietary habits such as consuming more cheese and fruit were found to be beneficial.
Interestingly, this is not the first study to find a link between cheese consumption and mental well-being. A study published in the journal Nutrients found a correlation between regular cheese consumption and cognitive health in the elderly population. Analyzing data from 1,516 participants aged 65 and above, those researchers found that individuals who regularly ate cheese tended to have better cognitive function scores.
While the new study provides compelling evidence of the causal relationship between mental wellbeing and healthy aging, it has some limitations. For instance, the study focused on individuals of European descent, so the findings may not be generalizable to other populations. Future research should investigate whether these relationships hold true across different ethnic groups.
Nevertheless, the results suggest that strategies to enhance mental health could significantly improve aging outcomes.
“Our results underscore the imperative to prioritize mental well-being in health policies geared towards fostering healthy aging, and propose that interventions to remediate healthy aging disparities related to suboptimal mental well-being could target promoting healthy lifestyles such as restricting TV watching time and avoiding smoking; monitoring performances and physical functions such as enhancing cognitive function and regulating adiposity; and preventing common chronic diseases,” the researchers concluded.
The study, “Mendelian randomization evidence for the causal effect of mental well-being on healthy aging,” was authored by Chao-Jie Ye, Dong Liu, Ming-Ling Chen, Li-Jie Kong, Chun Dou, Yi-Ying Wang, Min Xu, Yu Xu, Mian Li, Zhi-Yun Zhao, Rui-Zhi Zheng, Jie Zheng, Jie-Li Lu, Yu-Hong Chen, Guang Ning, Wei-Qing Wang, and Yu-Fang Bi.
