To comply with a new sesame allergy law, some businesses add — sesame

Four-year-old Mia McDermott just kept getting sick. Throughout January, she had persistent headaches, vomited frequently and became dehydrated, and every time she got better, she’d get worse again. Even after eating one of her favorite foods, a Wendy’s cheeseburger, Mia became violently ill, said her mother, Jessica McDermott.

McDermott was baffled: Her little girl was allergic to sesame, but she was eating only foods she had always eaten safely.