Skip to content

How Can Population Health Science Improve Health?


Population health science can improve health by providing an integrated, cells-to-society understanding of what causes health problems and what helps to solve them. Below are four important examples (Improving children’s lives to create healthy adults, Creating healthier environments, Helping us all make healthier choices, Changing discriminatory policies) of how population health science matters:

Improving children’s lives to create healthy adults

Decades of work by developmental psychologists, epidemiologists, and neuroscientists has shown that the experience of abuse, neglect, and other traumatic stressors have a profound effect on a child’s developing brain and body.

Childhood abuse and neglect have been linked to poor school performance, smoking and drug use, suicide attempts, and a host of health problems including heart, liver and lung diseases. Interdisciplinary scientists have traced out the social, psychological, and biological pathways that connect experience in the family and neighborhood to these health outcomes.

State governments have now begun to look for research-informed approaches to reducing abuse and neglect. Both Washington and California have passed legislation to promote polices to combat these problems, and other states have considered or passed related measures. In part, these efforts were spurred by population health research showing high rates of abuse and neglect among children – for example, one study showed that one in eight American kids experience this by the time they are 18. Research is currently underway to find out what combination of services works best to reduce this or mitigate its effects: parenting programs, mental health services, community supports for at-risk families, making school environments more compassionate, strengthening youth development and prevention programs, and other approaches.

Creating healthier environments

What draws you to go outside to exercise? Maybe green spaces, sidewalks, a neighborhood with interesting places to go and a low crime rate?

Population health research has shown that all of these are important for increasing physical activity among neighborhood residents.  However, the decisions that shape neighborhood characteristics are seldom made with health in mind. The city planners and elected officials who make the zoning rules consider many other things – why not health?

Population health science contributes to a widespread movement for “health in all policy”.  Here’s a recent example: A team at Johns Hopkins University measured the health impact of a rezoning effort in Baltimore, Maryland to determine how the existing plans could be modified to improve health. The team assembled expertise and research from medicine, behavioral science, epidemiology, environmental health science, law, sociology and criminology to estimate the health impact of the proposed changes. Their results showed that planned changes to the code – promoting more mixed-use development and making public transportation more accessible – would have important health benefits.  However, they also showed that mixed-use development could have negative effects on health: by making alcohol outlets more disproportionately concentrated  in disadvantaged neighborhoods, it could increase crime, deter physical exercise, and increase stress.  Because of this work, the code was revised to include a new provision prohibiting the location of new alcohol outlets within 300 feet of an existing one.

Helping us all make healthier choices

You’ve been there – in a restaurant or grocery store, struggling over whether to go for the rockfish or the ribs, the croutons or the kale.

For many customers trying to make healthy choices, nutrition information isn’t useful unless it’s meaningfully framed.  Simply seeing the number of calories next to a favorite burger may not compel us to change our order – we need to know what those calories mean.

Research that integrates insights from psychology and behavioral economics with nutrition and food science shows that simple, meaningful symbols can encourage healthier choices.  For example, traffic light labels signaling red (for stop) and green (for go) helped hospital workers make healthier choices in their cafeteria, and patrons with low education levels benefited as much as others.   Similarly, adolescents purchase fewer sugary drinks when labels highlight the amount of exercise needed to burn off the calories in the drink. And when calorie labels on restaurant menus are placed in the context of recommended daily caloric requirements, it can help increase their benefit. These studies have informed parts of the Patient Protection and Affordable Care Act, policy discussions on front-of-package labeling in the United States, and industry efforts to promote healthier products. You may already see some of these new labels at a restaurant or grocery store near you!

Changing discriminatory policies

Evidence that discriminatory policies undermine minority populations’ health are a powerful lever for policy change. Mark Hatzenbuehler knows this.

Mark is a psychologist who set out to understand the ways in which society embeds and perpetuates stigma in institutions and policies and the ways in which these institutions and policy harm the health of stigmatized populations.  His work led to key insights that helped gain rights and protections for lesbian, gay, bisexual, and transgender (LGBT) populations.

Mark found that there are many ways in which cultural norms, practices, and policies create and reinforce stigma for sexual minorities in the social environment – examples include state-level bans on gay marriage, local prevalence of hate crimes against sexual minorities, and local views on the acceptability of homosexuality.  His research showed that these types of “structural stigma” have robust and far-reaching impacts on the health of LGBTs, but not heterosexuals.  Adverse health outcomes linked to structural stigma included maladaptive physiological stress responses in a laboratory setting; psychiatric disorders and substance abuse; and suicide and premature mortality.  He even found that eliminating anti-gay policies in one state lead to savings in health care costs – a 15% reduction in mental and medical health care utilization and costs, during a period in which health care costs increased for other groups state-wide. Mark’s work was used in amicus curiae briefs for cases related to state-based discrimination, including, in one exemplary case, a federal court ruling striking down California’s ban on same-sex marriage (Proposition 8).