Public health and population health interventions use logic models to identify evidence-based approaches to produce measurable improvements. The use of a logic model implies that a logical sequence of actions will inevitably lead to a desired outcome. If this, then that. If we do X intervention, we will affect people’s knowledge, attitudes, and beliefs which will lead them to change Y behavior. If we create a law that people have to wear seat belts, more people will wear seat belts. This theory of change can work, as in the case of the seat belt law. The sad fact is that, now, a lot of people wearing seat belts are also texting while driving. It’s a constant process to stay ahead of problematic human behavior patterns.

Despite our logic models, the reality is that people behave in illogical ways. The reasons people think, act and behave in the ways they do often in no way resemble anything logical. This begs the question why we rely on logic models to develop our strategies. And it explains why our strategies often do not work. Consider our country’s battle against the epidemic of obesity. Only a small fraction of the population meets the CDC’s exercise guidelines and even fewer consume the USDA recommendation for fruit and vegetable intake, despite pervasive advertising campaigns to the contrary. Yet, when the new iPhone comes out, everyone knows about it and a significant portion of the population reprioritizes their finances to acquire one. In other words, if people see enough value in something, they do make the effort.

We need to integrate behavioral economics into our models, where we look at the underlying reasons people do not make “logical” decisions and deploy interventions that address underlying drivers for those patterns of behavior. We know the reasons people do not eat as healthy as they should. Cost, convenience, and cultural norms drive behavior. If I have a SNAP card, and I can buy a Starbucks Frappuccino with that card, and one for my five-year-old to keep her content while I shop for groceries, why wouldn’t I? They are delicious and satisfying. Buying broccoli is a less appealing alternative, requiring more effort to prepare, not to mention the effort it takes to get my daughter to eat it. The same goes for exercise. If I have a choice between going for a run or binge watching my favorite Netflix series, the odds are I will do the latter. Telling me that running is a healthier alternative is not enough to motivate me to change my behavior.

While we cannot legislate people’s activity choices, there are things we can do. We can create universal childcare and require that a nutrient dense menu and physical activity guidelines be met within that setting. In that way, we could ensure that significantly more children will be exposed to healthier habits, earlier in life. The SNAP program could be amended to only include nutrient-dense food options. Calories are not nutrients. In the U.S., we have a population that is overfed and undernourished. Policy makers must begin to take some responsibility for this, given the fact that the Center for Medicare and Medicaid bears the lion’s share of the healthcare costs associated with preventable chronic health diseases. While logic models and evidence-based interventions have their place in public health policy, they often fall short due to the complexity of human behavior. Applying behavioral economics into policy making can provide valuable insights into why individuals make seemingly illogical choices and guide the development of interventions that address root causes. Integrating behavioral considerations into programs like SNAP and the U.S. physical activity guidelines can create environments that promote better health outcomes. Without these adjustments, achieving meaningful improvements in public health will remain elusive.