Wine, sushi, deli meat ... licorice? Perhaps. A new study suggests that licorice consumed during pregnancy could detrimentally affect a woman's offspring. Researchers in Finland say the culprit is glycyrrhizin, a tongue-twister of a sweetener that naturally occurs in the licorice plant and is also added to teas and herbal supplements, among other things. Eat it, and your levels of the stress hormone cortisol take a jump, reports the New York Times; for pregnant women, that bump could tamper with a fetus's developing nervous system. Licorice is often touted as a remedy for ills as varied as asthma and body odor, but for pregnant women, the potential negative effects outweigh any benefits, lead author Katri Raikkonen tells the Times. "Insofar as you can avoid it during pregnancy, you should do so."
Raikkonen's team reports in the American Journal of Epidemology that almost half of the 1,049 mothers studied ate licorice before giving birth in 1998. The 11% who consumed the most—more than 500mg of glycyrrhizin per week, or about 8.8 ounces of pure licorice—had offspring who, by age 13, scored an average of seven points lower on IQ tests and had three times the risk of ADHD as compared to the lowest exposure group. Daughters tended to reach puberty earlier, which the researchers say is associated with physical and mental disorders. Live Science reports that the FDA and the WHO have no warnings against licorice or glycyrrhizin during pregnancy, though Finland's national health institute last year added it to its list of foods best skipped while expecting. Red Twizzlers, however, are safe. (Potatoes may be another no-no for prospective mothers.)