Childhood health and family ties boost adult optimism, study finds

By Dr. Liji Thomas, MDMay 1 2025

The largest global study of its kind reveals how childhood health, family belonging, and even attending religious services influence adult optimism, offering new insight into how early environments shape our mental outlook for life.

Study: When the glass is half full: early life experiences and adult optimism in 22 countries. Image Credit: Ollyy / Shutterstock

Optimism is a key trait to approaching life with resilience and experiencing happiness in daily life. However, its childhood correlates have not been studied in detail. A recent study in the journal npj Mental Health Research examined the relationship between early life experiences and optimism in adulthood.

Introduction

Wellbeing is increasingly a target of health policies as an important parameter of social development. One factor that promotes wellbeing and health is dispositional optimism—“a generalized expectation that good things will happen.” Optimists have lower mortality and cardiovascular risk and lower rates of mental illness. They also tend to follow healthier lifestyles.

This trait can be influenced by environmental factors, with heritability estimated at approximately 25%. Since it tends to be stable by adulthood, factors that can be modified to promote its development in childhood should be identified. These include family relationships, adverse childhood experiences, parental divorce, and religious upbringing. These interact with the regional culture, as suggested by the Ecological Systems Theory.

Earlier research in this area mostly came from the US and Europe, leaving a significant knowledge gap. The current study sought to fill this gap by a multinational assessment of childhood factors in relation to regional differences in culture that shape adult optimism levels.

Study findings

The data for this study were obtained from the Global Flourishing Study (GFS), which covers 22 countries. It included nearly 203,000 participants.

Most participants (89% and 80%, respectively) had good or somewhat good relationships with their mother and father, respectively. Most had married parents and reported that they either “lived comfortably” or “got by” financially in childhood (~75%). Over 80% had no history of abuse and felt they belonged in their families.

Only 64% reported being in excellent or very good health as children, and 41% attended religious services at least once a week.

Overall analysis

Each of these factors was significantly associated with adult optimism in one or more of the countries studied. For instance, children who had good (vs bad) relationships with their mothers had adult optimism scores that were, on average, 0.17 points higher (on a 0–10 scale), and those with good relationships with their fathers had scores 0.07 points higher.

The greatest and most widespread negative impact on adult optimism of any single factor was a reduction of 0.26 points on the 0–10 scale associated with “feeling like an outsider.” Indeed, Attachment Theory predicts that responsive and loving caregivers promote secure attachment, thereby fostering trust and self-worth in children.

Childhood abuse was also linked to a reduction of 0.24 points in optimism. Moreover, in most countries, optimism was lower if parents were divorced or single. Both childhood abuse and divorce may promote a negative or hopeless mindset in children, reducing their will and ability to try to create positive outcomes.

However, the impact of parental divorce may be influenced by the national culture in which it occurs. For instance, having divorced parents in Japan or Sweden, as well as single parenthood in Australia or Egypt, predicted higher adult optimism, perhaps because of the cultural acceptance of these family structures.

The greatest positive impact on adult optimism was produced by health. Excellent vs. good health was associated with a 0.43-point increase in the optimism score, and attending religious services at least weekly (vs. never) was associated with a 0.26-point increase. Interestingly, children born in earlier years (1953–1963) had scores 0.20 points higher than those born later (1998–2005). The pooled results also showed that females reported higher optimism than males on average, with a 0.18-point difference. Regarding immigration status, while being native-born versus non-native born was not significantly associated with optimism on average across all countries, the data suggested it was a relevant factor in at least some national contexts.

Country-specific analyses

Country-specific analyses revealed significant differences from the meta-analysis. In this case, the most relevant factors were self-rated health in childhood, birth year, sex, and religious affiliation, which affected adult optimism scores in over 50% of the countries assessed, albeit to widely differing extents.

Health in childhood was linked to increased adult optimism across many countries with diverse cultures and lifestyles, especially in wealthy countries. Feeling financially secure also predicted optimism in some wealthy countries but not in most low- or middle-income countries.

In high-income countries, national wealth and stability enhance the positive effects of household-level financial wellbeing and childhood health. Children with material security and good health in highly industrialized countries not only have better resources (money, social status, networks, power, and knowledge) but are more likely to use them to overcome obstacles more effectively.

In politically unstable, conflict-torn, or developing countries, such as Israel, India, or Nigeria, having material resources might be less critical, as the children still cannot use them to forge their way ahead.

Relationship with parents was relatively unimportant as a predictor of optimism when analyzed by country. Individuals reporting a poor relationship with their parents made up less than 5% and less than 10%, respectively, of the sample in many countries, which could affect the analysis. The large population of countries like India, where few children report having a poor relationship with their parents, could skew the population-weighted analysis.

Interestingly, adult optimism in some of the most secular countries, such as Japan, Hong Kong, Germany, and the United Kingdom, was higher among those who had regularly attended religious services during childhood. This novel finding reports direct and dose-dependent associations between these factors for the first time. This might imply that people with a strong sense of hope, faith, and meaning in life are more likely to become part of religious congregations, even in such settings.

Study limitations

It is important to note several limitations mentioned by the study authors. Optimism was measured using a single item from the Revised Life Orientation Test (LOT-R), which might be subject to measurement error or interpretation issues across cultures. All childhood experiences were reported retrospectively by adults, raising concerns about recall bias – current optimism levels could influence how people remember their childhood. Furthermore, this was an observational study, meaning it can show associations but cannot prove that these childhood factors directly cause changes in adult optimism. There may be other unmeasured factors (confounders) that influence both childhood experiences and adult optimism. The researchers also noted potential statistical issues, such as collinearity between certain related childhood factors (e.g., parental relationships and feeling like an outsider).

Conclusions

"This is the first study that examines a wide range of childhood correlates of adult optimism simultaneously across multiple countries." Its findings align with prior research, indicating the impact of multiple childhood factors on the development of optimism and the potential for deliberately cultivating this trait.

Earlier approaches to targeting these factors have shown small and transient benefits, such as mindfulness techniques or the Best Possible Self program. A more effective way to foster adult optimism might be to identify and specifically work on equitably improving childhood conditions associated with lower optimism outcomes in the population. This, in turn, will improve their chances of doing well and enjoying better health, both physically and mentally, throughout life.