How Does a Poppy Seed Bagel Trigger a Positive Drug Test?

A mother in Maryland said that eating a poppy seed bagel caused her to test positive for opiates while she was giving birth, according to news reports. But how does this happen?

The woman, Elizabeth Eden, ate a poppy seed bagel the morning she gave birth to her daughter in April, according to local news station WBAL. Eden was in labor when her doctor told her she had tested positive for opiates.

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