A new study highlights the important role that mental wellbeing plays in healthy ageing, regardless of socioeconomic status. By analysing genetic data from more than 2.3 million Europeans, researchers found that better mental wellbeing leads to healthier ageing, characterised by greater resilience, better self-rated health and improved longevity. Interestingly, they also identified certain lifestyle choices, including being active, not smoking and eating cheese and fruit, as being beneficial for mental wellbeing and healthy ageing.
The results were published in Nature Human Behavior.
Human life expectancy has increased significantly in recent decades, posing challenges to 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 well-being has received less attention. This study aimed to explore the causal relationship between mental well-being and healthy aging, and to determine whether this relationship is independent of socioeconomic status.
The study used a technique known as Mendelian randomization to study the causal relationship between mental well-being and healthy aging. This method uses genetic data to determine whether an observed association between two traits is causal or simply correlational. By using genetic variants as indicators of exposure, Mendelian randomization helps mitigate biases commonly seen in observational studies, such as confounding and reverse causality.
The researchers analyzed data from eight genetic datasets spanning more than 2.3 million individuals of European descent. These datasets included information on five key characteristics of mental well-being: general well-being, life satisfaction, positive affect, neuroticism, and depressive symptoms. In addition to mental well-being, the study considered three socioeconomic indicators: income, education, and occupation.
The study was conducted in two phases. In the first phase, the researchers assessed causal associations between mental well-being characteristics and various aging phenotypes, including resilience, self-rated health, healthy life span, parental life span, and longevity. They also examined whether these associations were independent of socioeconomic status.
In the second phase, they investigated potential mediating factors that might influence the relationship between mental well-being 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 disease, diabetes).
The study found a strong causal relationship between better mental well-being and healthier aging. Specifically, individuals with higher levels of mental well-being had significantly higher scores on the genetically influenced phenotypes of aging (aging-GIP), as well as greater resilience, better self-rated health, longer healthy lifespan, and longer parental lifespan.
For example, the study found that a genetically determined increase in general well-being was associated with a substantial increase in age-related GIP (1.21 standard deviations), resilience (1.11 standard deviations), self-rated health (0.84 points), healthy life span (odds ratio of 1.35), and parental life span (3.35 years). However, no significant association was found between general well-being and longevity (odds ratio of 1.56).
Importantly, the study demonstrated that the relationship between mental well-being and healthy aging persisted regardless of socioeconomic status. Although higher income, education, and occupational achievement were all associated with better mental well-being, the positive impact of mental well-being on aging outcomes remained significant even after adjusting for these socioeconomic factors. This suggests that mental well-being exerts a robust and independent influence on healthy aging.
The researchers also identified several lifestyle factors that contribute to mental well-being and, therefore, healthy aging. Among these, physical activity and avoiding smoking were associated with better mental well-being and healthier aging. Other influential factors included cognitive performance, age at smoking initiation, and taking certain medications, which also played a role in the relationship between mental well-being and aging. Additionally, dietary habits such as increased cheese and fruit consumption were found to be beneficial.
Interestingly, this study is not the first to link cheese consumption to mental well-being. A study published in the journal Nutrients A study has found a correlation between regular cheese consumption and cognitive health in older adults. Analyzing data from 1,516 participants aged 65 and older, researchers found that people who regularly ate cheese tended to have better cognitive function outcomes.
While the new study provides compelling evidence of a causal relationship between mental well-being and healthy aging, it has some limitations. For example, the study focused on individuals of European descent, so the results may not generalize to other populations. Future research should examine whether these relationships hold true for different ethnic groups.
Nevertheless, the results suggest that strategies aimed at improving mental health could significantly improve aging outcomes.
“Our findings highlight the imperative to prioritize mental well-being in health policies aimed at promoting healthy aging, and suggest that interventions to address disparities in healthy aging related to suboptimal mental well-being could aim to promote healthy lifestyles such as restricting television viewing and avoiding smoking; monitoring physical performance and function such as improving 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.
