But this raises an important, policy-related question. Why do some people invest more in a healthy lifestyle than others?
Health economists argue that better educated people are more likely to choose healthier lifestyles. This is in part because future returns for healthy behaviour (in terms of both health and lifetime earnings) are higher for the better educated, thus leading them to invest more in a healthy lifestyle.
People of higher educational background are on average less likely to smoke, abuse alcohol, and will exercise more, eat healthier foods, and have more frequent health checks than the average population.
This can be explained by a variety of different reasons. For instance, students with healthier lifestyles may be more efficient in acquiring knowledge so they tend to perform well in their education. One could also imagine that people who value future consumptions more than current consumption will stay in school for longer, work more at younger ages and invest more in positive health-related behaviours.
New research in the area
Most of the existing evidence cannot truly separate the true effect of education itself on health habits from other confounding factors as mentioned above.
My colleague and I have recently conducted research to address this important question. We used an econometric technique to empirically identify the causal effect of education on a range of health behaviours among Australian adults aged 22 to 65. We rely on school reforms in Australia on minimum compulsory school-leaving age as a natural experiment to identify this causal relationship.
This research shows that among Australians, there is a sizable effect of staying an additional year in school on later health habits, including diet, exercise, and the decision to engage in risky health behaviours.
Results also show that the positive effect of staying an additional year in school on health behaviours is larger for Australian women than for Australian men. Interestingly, previous studies from UK and Germany have found the opposite, that is that the health benefits from staying an additional year in school are larger for men than for women in these two countries.
Does context matter?
While we found a positive effect of education on health among Australians, previous studies from other countries indicate this is not necessarily true in different countries.
Studies in Denmark and South Korea found similar evidence as ours, but no such evidence has been found in the US, the UK and Germany. This might be a reflection of the differences in the education and health care systems, or an interaction between these two systems, across different countries.
Not only the context of the residing country but also the context in terms of early-life family circumstances may moderate the causal effect of education on health behaviours. Our study demonstrates that the magnitude of the education effect is larger for people from a poorer background when they were about 14 years old.
There are many theories to why more education will lead to better health behaviours. We provide evidence that one of the reasons is because more education raises the individual’s conscientiousness levels and the perceived sense of control over one’s life, which in turn contributes to adopting healthier lifestyles.
The intuition is that individual with different education levels may differ in their psychological capacity to make behaviour changes. This echoes some psychological theories which claim that in order to adopt certain behaviour or change certain lifestyles, individuals need to be “ready” to change and feel able to do so.
This new finding may also explain why in previous studies other important individual attributes such as cognition function and knowledge can only explain some, but not all, of the causal effect of education on health behaviours.
The direct implication of these findings is that an increase in spending on education can lead to the overall improvement of the nation’s health. This provides a way of saving money for our health system, given that preventable diseases are often directly related to health habits.
While we have found an important effect of education on later health behaviours for people who were directly affected by changes in the compulsory schooling laws in Australia, we have also demonstrated that there is a considerable difference in the education effect across different groups of individuals.
Future research – especially qualitative research – should come back to investigate how different predetermined characteristics and early home environments can moderate the causal effect of education on health behaviours.
Given that an additional year of schooling also caused a change in psychological traits that are known to govern healthy behaviour, there is scope for later policy interventions to try to improve personality traits that are related to healthy habits.