Becca, who writes Corn Allergy Girl, also gets a lot of her produce from local farms. The rest she grows. She goes to a specific butcher and meat processor who will custom-process whole animals for her without using lactic acid or citric acid. She has two fridges and several freezers to store food for the winter, when fresh vegetables are less abundant. “I go all Little House on the Prairie on the weekend,” she said, “pickling things and shredding them and baking them.” She counts herself lucky to live in the Pacific Northwest, where there are many organic, local farms. It’s harder to find fresh food in many other parts of the country, and it’s much harder to do so on a budget. “Your dollars just don’t go as far as if you’re getting a bunch of Chef Boyardee. It’s very cheap to eat canned, preserved food,” Becca said. She had to run GoFundMe campaigns, for example, for friends who couldn’t afford to buy chicken from a source they can tolerate.

The diet of someone with a severe corn allergy is in some ways the ideal diet for a certain type of foodie: fresh, local, free of preservatives and processed foods, the provenance of every ingredient intensely cataloged. It’s just not exactly by choice.

Knowing how to avoid foods with corn is one thing; knowing how to navigate social situations where danger lurks in every corner is another.

Robinson said that she has two rules when eating out with friends now. First, eat beforehand. Second, order a San Pellegrino and an appetizer for the table to share, which deflects the inevitable concern from the waitstaff. “They’re nice, but people really feel they can find something, and they try. You have to keep saying, ‘No, I can’t, I can’t,’ and everybody feels bad.”

Cassandra Wiselka, whose 5-year-old is allergic to corn, has written about the problem of Halloween. Virtually all mass-produced candy contains high-fructose corn syrup. Her son still goes trick-or-treating, but she switches out the candy he collects with corn-free alternatives: lollipops, gummy bears, and “fancy expensive chocolate that we don’t even buy for ourselves.” She makes and freezes big batches of corn-free cupcakes and pizza to bring to birthday parties. It’s hard, she says. “He still gets upset at birthday parties and things where he has to have his own special food.” They recently had to turn down a birthday party that was moved to a pizza place at the last minute because they didn’t have time to make safe pizza to bring.

Wiselka’s family moved from Germany to California when her son was 18 months old. He seemed to get worse after the move. It’s hard to say exactly why, but Wiselka noticed that “in Germany, things are a lot less processed, food-wise. At least not processed as much with things like corn.”

The one thing Robinson told me she really misses is being able to travel without worry. She did make a trip to Hawaii recently, after much advance planning. She picked Hawaii for the scuba diving. When she dives, she has to watch out for a few specific things—that her wetsuit has not been washed with a corn-containing detergent, that her dive partners have not been eating corn chips. But once she’s in the water, she’s calm. Sure, scuba diving can kill you if you aren’t careful (the most recent data show that 40 to 50 people die while diving in North America every year), but she can be sure there is no corn in water.

“You don’t realize you’re carrying around this extreme sense of alertness,” she said. “That level of hypervigilance that you have for things that you could touch or breathe in is gone. You’re breathing air that you know is safe and you know the actual oxygen content of. It’s just incredibly freeing.”