In late 2013, some colleagues and I applied for funding from the University of Minnesota’s Healthy Foods, Healthy Lives Institute. Because of the name of the institute, we thought “People think of local and organic foods as healthy foods, and they think of an illness-free life as a healthy life, so why not look at the relationship between local and organic foods and food safety?”
So we submitted a proposal, and it got funded. It was a pretty small amount of money, as far as these things go–less then $5,000–and our research team eventually split along disciplinary fault lines. But because I could not look at the relationship between local and organic foods on one hand and food safety on the other hand in a way that was methodologically satisfactory to me, I chose to look instead at the relationship between farmers markets and food-borne illness.
Four years (and a New York Times op-ed) later, I am happy to note that my article titled “Farmers Markets and Food-Borne Illness,” coauthored with my former Master’s student Jenny Nguyen, is now published (gated; please email me for a copy) in the American Journal of Agricultural Economics.
A little over a year ago, I published an op-ed in the New York Times titled “Farmers Markets and Food-Borne Illness.”
That op-ed was based on the findings of a similarly titled working paper of mine, which one of the New York Times editors had gotten wind of after I first discussed it on this blog during the summer of 2015.
In my op-ed, however, I mentioned that I would soon post an updated version of our paper. But things got busy, and though I worked quite a bit on it here and there, I did not get to finish it until a few weeks ago.
(And by “finish,” I mean “stop working on it until it is returned to us with reviewer comments about how to improve it before it can get published.”)
Here is the new version. The major innovation is that we now exploit both the longitudinal nature of the data as well as a source of plausibly exogenous variation for the number of farmers markets in a given state in a given year. This obviously makes for much stronger results than we used to have. Here is the abstract of this latest version:
(January 16, 2016 Update: If you came here from the New York Times website, thank you for your visit, and please note that the findings discussed below have changed slightly due to our incorporating two more years of data since this was posted last summer. Our new findings will be presented and discussed in an updated version of the working paper discussed in this post, which I am hoping to release before the end of March 2016. In the meantime, some of those new findings are discussed in the New York Times article.)
When I arrived at the University of Minnesota in the fall of 2013, a few colleagues and I applied for a seed grant from the university’s Healthy Foods, Healthy Lives Institute by submitting a proposal to look at the impact of local and organic foods and food safety.
After working on it for almost two years, I am happy to finally be able to circulate my new paper titled “Farmers Markets and Food-Borne Illness,” coauthored with my colleague Rob King and my student Jenny Nguyen, in which we ask whether farmers markets are associated with food-borne illness in a systematic way. In order to answer that question, we use a US state-level panel data set for the years 2004, 2006, and 2008-2011 (i.e., the years for which we had a full data set).
Here is the abstract:
We study the relationship between farmers markets and food-borne illness in the United States. Using a state-level panel data set for the period 2004-2011, we find a positive relationship between the number of farmers markets per capita on the one hand and, on the other hand, the number of reported (i) outbreaks of food-borne illness, (ii) cases of food-borne illness, (iii) outbreaks of Campylobacter jejuni, and (iv) cases of Campylobacter jejuni. Our estimates indicate that a 1% increase in the number of farmers markets is associated with a 0.7% (3.9%) increase in the total number of reported outbreaks of food-borne illness (Campylobacter jejuni), and a 3.9% (2.1%) increase in the total number of reported cases of food-borne illness (Campylobacter jejuni) in the average state-year. Our estimates also suggest that a doubling of the number of farmers markets in the average state-year would be associated with an economic cost of over $900,000 in additional cases of food-borne illness. When controlling simultaneously for both the number of farmers markets and the number of farmers markets that accept SNAP benefits (i.e., food stamps), we find that they are respectively associated positively and negatively with reported food-borne illness outbreaks and cases. Our results are robust to different specifications and estimators, and falsification and placebo tests indicate that they are unlikely to be spurious.