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You might have heard at some point that eating poppy seeds could lead to a positive drug test. Turns out, the "poppy seed defense" is no health myth — the tiny black seeds can actually alter toxicology screening results, and a pregnant woman learned this the hard way. Elizabeth Eden was in labor back in April at the University of Maryland St. Joseph Medical Center in Towson, Maryland, when her doctor came in with some surprising news. "I was in labor, I was sitting on the bed. I was having contractions on a Pitocin drip and the doctor came in and said I tested positive for opiates," Eden told NBC affiliate WBAL-TV. Eden, who had eaten a poppy seed bagel that morning for breakfast, said she recalled learning that the seeds could alter drug test results and asked the doctor to test her a second time. According to her account, the doctor refused to do another test and told Eden that she had already been reported to state authorities. The newborn was kept in the hospital for five days and a caseworker was assigned to check up on the mom and baby, named Beatrice, after she went home. "It was traumatizing," Eden told WBAL-TV. How can poppy seeds — a common topping on breakfast pastries — alter drug test results?

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Poppy seeds come from a species of poppy plant called Papaver somniferum (commonly called the opium poppy), which has red and pink flowers. People have been cultivating the poppies for culinary and medicinal purposes for thousands of years. Contrary to popular belief, the poppy seeds themselves do not contain opium. The opium is found in the milky sap that oozes from cuts in an unripe seedpod — which is scraped off and dried, according to the US Drug Enforcement Administration. The rubbery opium resin is used to make opiates like morphine, codeine, and heroin — powerful painkillers that are also used as illicit drugs in many parts of the world. However, the harvesting process can cause opium residue to coat the seeds — the same ones we enjoy on our bagels and muffins. So yes, although poppy seeds are legal to eat, they can contain enough opium to trigger a positive screening for opiates. This is called a "false positive," or a test that incorrectly indicates someone is using drugs. How much do you need to eat? It's hard to say, because the amount of opium coating the seeds varies depending on where the poppy plant is grown and how the seeds are harvested and processed. But it takes more than a few seeds. Previous research has shown that eating a serving of poppy seed cake can cause the morphine concentration in a urine sample to be in "the thousands of nanograms per milliliter (ng/mL)" and a bagel topped with the seeds can cause levels to be in the hundreds, according to F. Leland McClure, director of medical affairs at Quest Diagnostics, a major clinical laboratory in the US. The threshold for a true positive drug screening — or the sensitivity of the drug test — also matters.

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