America spends an astonishing amount — at least $2.5 trillion — on health care each year, yet we aren’t as healthy as we could or should be. For every dollar we spend on health care, less than a nickel goes toward policies and programs aimed at public health and prevention, such as community farmers’ markets and wellness initiatives that encourage healthy living for all ages. We need to shift the focus of the U.S. health care system from treating illness to creating an environment that is conducive to better health.