Two important, but quite different, events over the past few weeks made me reflect on what it means to adopt a true “public health” approach to improving population health, and reminded me of the often cited quote from Rudolf Virchow, famous physician, anthropologist, pathologist and politician that “mass diseases require mass solutions”.

A few weeks ago Philadelphia became the first major city in the United States to adopt a “soda” tax. The 1.5-cent per ounce tax on beverages (including not only sugar-sweetened beverages but also diet sodas) was argued for on the basis of its revenue-generating potential, and not on the basis of its health impact. The revenue generated by the tax will primarily be dedicated to provide much needed funds for universal pre-kindergarten (pre-K) education in Philadelphia. It is interesting to consider the long-term health consequences of strengthening pre-K education given the established relationship between childhood conditions possibly affected by pre-K (such as subsequent educational attainment and exposure to adversity) and health much later in life.

Research has also documented links between intake of sugar-sweetened beverages and obesity and diabetes, although clearly it will be difficult to detect short-term effects of the tax on these conditions, given the magnitude of the tax and the many other contributing factors. Few would disagree however, that in the long term, anything that shifts the distribution of the consumption of sugar sweetened beverages to lower levels for the population as a whole is likely to have beneficial impacts on population health down the road. There are of course a number of unknowns, and evaluation of the impact of the tax will be important (especially given its explicit link to pre-K education and the fact that it encompasses other beverages as well).

The second event, much more worrisome and disturbing of course, was the emergence yet again of new instances of gun–related deaths, a sadly common occurrence in the United States in recent months (and years): most recently the senseless shooting deaths of two young black men in encounters with white police officers and two mass shootings of police officers by well-armed lone shooters, in Dallas and in Baton Rouge. Although it is tempting to seek the causes of these deaths in immediate prior events (the policemen feared for their lives, the lone shooters were “disturbed”), the constant and regular repetition of these events makes them the “mass diseases” that Virchow so eloquently alluded to. The “mass causes” are not difficult to identify: they are the pervasive (sometimes subtle often structural) racism that is a persistent characteristic of our society, and the broad availability of guns in the United States. (All the events were suffused with guns: the two men were killed by guns and were themselves carrying guns, and in Dallas even protesters were carrying AR-15 rifles).

There are things that we can do, indeed that other societies do quite effectively, to reduce levels of gun violence, by simply restricting access to guns. Pervasive racism is of course much more difficult to address and first will require first open recognition of the problem by society as a whole, giving it the importance that it deserves in public discourse and policy, and then implementing a concerted set of strategies at multiple levels and in many domains.

In his seminal paper “Sick individuals and sick populations”, Geoffrey Rose, another public health giant, argued for population approaches to disease prevention, approaches that involve broad social and environmental change. Rose recognized the importance of focusing on individuals at “high-risk” within a population, but noted the critical importance of the population approach and the focus on “mass causes”. The consumption of sugar-sweetened beverages is one example of a behavior that is driven largely by population-level factors such as availability, cost, and marketing of beverages, as well as the social norms closely linked to these factors. Soda consumption is a behavior that can be modified and intervened on by policy.

Gun violence and the senseless deaths of African Americans in police encounters are two other major public health problems driven by population-level factors – gun availability and racism. Both issues scream out for Virchow’s mass solutions and for Rose’s population approach.