Springmann et al. (2018) on Health-Motivated Meat Taxes

 Springmann M, Mason-D'Croz D, Robinson S, et al. Health-motivated taxes on red and processed meat: A modelling study on optimal tax levels and associated health impacts. PLoS One. 2018;13(11):e0204139. Published 2018 Nov 6. doi:10.1371/journal.pone.0204139

The authors look at the health impacts of an increase of one serving per day in the consumption of red and processed meat. (Red meat here is beef, pork, and lamb, despite what the ads have told us; processed meats include sausage, hot dogs, and many deli-style lunchmeats.) They monetize these health impacts, and then examine taxes that would internalize the incremental health costs; here's a schematic representation of their analytic approach.

Red and processed meats come out of the study as fairly lethal, accounting for something like 4.4% of deaths. In high-income countries, "internalizing" the mortality and morbidity effects would raise prices of red meat by about one-fifth, and more than double the prices of processed meat. These price changes would result in lots of substitutions in terms of food consumption, and meat-related deaths worldwide would decline by some 9%. The remaining meat-related health care costs would exceed meat tax revenues.

While I learned a lot from the useful exercise presented in Springmann et al. (2018), I don't think that it sheds much light on "optimal" meat taxes, at least when that term is used in the Pigovian sense (which the authors reference). Their approach treats all incremental meat-related health care costs as external, that is, as if they are ignored entirely by the consumer. But people engage in lots of risky activities even when they know the risks and even know that they will bear the costs if the risks materialize. Is the additional utility that people get from that incremental serving of meat more valuable than the additonal (expected) health care costs? We can't know the answer to this question from the approach taken in the article. We don't know benefits, we don't know what portion of costs are truly external, and we don't know the extent of underweighting of non-externalized costs, so-called internalities. Hence, this approach does not possess the building blocks required to provide reliable estimates of Pigovian meat taxes -- a point similar to one I raised concerning the analysis in Meatonomics. I suspect the underlying issue (with Springmann et al. (2018)) is a reliance on a cost-of-illness approach, which is inadequate for capturing economic optimality.