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I Will Die of Listeriosis Before I Wash The Outside of My Avocado

I refuse to worry about one more thing.
Cut open avocado
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I have actual, clinical, anxiety that manifests as nagging fears about elaborate, highly specific scenarios that will maim or murder me (a.k.a. I read the news today, oh boy). To make matters even more fun, my brain interprets these fears as premonitions, which become increasingly real the more I worry about them. (This isn't funny, per se, but it is a little ridiculous. During a particularly dark stretch, I trashed a pound of pasta because I became convinced that I had insufficiently rinsed the pasta pot and now was going to be poisoned by chemicals from the soap residue.) I don't say this to make light of a very real mental health problem—for which, I assure you, I'm receiving adequate professional care—but it does serve as useful context for me to (hopefully not literally) die on the hill of refusing to wash the outer skin of my avocados.


Earlier this month, the Food and Drug Administration published the results of a 14-month study from 2014 designed to measure the prevalence of Listeria monocytogenes in avocados (70 percent of the sample lot was imported, 30 percent domestic). Initial findings showed traces of L. monocytogenes on over 17 percent of avocado skins, which sounds bad. But: "Three months into the assignment, the FDA updated its approach to its Listeria monocytogenes testing to focus on the avocado pulp (i.e., the fruit’s edible portion), as opposed to its exterior, to better evaluate public health concerns associated with the pathogen, namely the extent to which it may be present in the part of the fruit that people eat."

The rate of contamination in the "part of the fruit that people eat"? About 0.2 percent—along with a slight added concern that the edge of the knife blade could potentially drag bacteria from the skin into the flesh.

So, how worried should we be about this? Cooking Light covered the study by writing "Why You Really Do Need to Wash Avocados Before Eating Them," and Quartz insisted, "Seriously, Wash Your Avocados Every Time" (despite stipulating that these stats have never manifested in a listeria outbreak tied to avocados). But personally—and please know I'm neither a doctor nor claiming that I talked to one for this piece, which is an act of openly biased opinion—I'm not going to worry about it at all.

For context: A 1996 study showed that about 5 percent of soft cheeses purchased in Italian grocery stores tested positive for L. monocytogenes—and I would love to eat soft cheeses from Italy. We've written about how caramel apples with sticks are prone to listeria contamination—and I ate a caramel apple on stick right here in the MUNCHIES office recently. A 2015 study found that 9.5 percent of deli meat samples here in the States tested positive for listeriaand I would never turn down a supermarket sample. And a 2017 overview of listeria studies regarding produce from grocery stores around the world showed a prevalence between 2 and 25 percent on unwashed vegetables in places like Korea, Brazil, and Greece—which is, of course, why you're supposed to wash them… but I've definitely chopped parsley (contamination rate: 5 percent) without a thorough cleaning first.

Listeria is dangerous—especially for people with weakened immune systems, the elderly, infants, and pregnant women. In fact, the higher rates of contamination in those items is precisely why women who are pregnant are told to avoid things like soft cheeses, deli meats, and unpasteurized milk. Approximately 260 people die annually from listeriosis, primarily members of those at-risks groups. That's more than the number of people who die from getting struck by lightning (a record low of 16 in 2017) but much closer to that statistic than, say, the number of people killed annually in cars (which topped 40,000 last year). You can play this game for everything and anything, but there's only so many ways you can mitigate your exposure to risk before you run into a balloon-boy scenario.

Thankfully, I don't fall into any of those listeriosis-prone populations right now. And as soon as I finish writing this blog, I will forget all about the bacteria on the skin of my avocado. Not because the task of washing it would be so onerous (according to the FDA, " also recommends that consumers scrub firm produce [which includes avocados] with a clean produce brush, and then dry it with a clean cloth towel or paper towel to further reduce bacteria that may be present," which is a little much), but out of an unwillingness to live in fear of the zero-point-two-percent-chance that my produce might contain harmful bacteria. Because qualifying food by the potential threat it poses is a slippery slope towards catastrophizing everything, truly everything, that makes life worth living.

I will, however, abstain from licking the outside of avocados to claim them as my own from now on.