The long list of foods to avoid during pregnancy seems to keep growing, and a new study suggests licorice is now included.
Research shows that children born to mothers who consumed large amounts of licorice while pregnant may be more likely to develop behavioral problems such as attention deficit hyperactivity disorder (ADHD).
The study, published in the American Journal of Epidemiology, comes from a team of Finnish researchers from the University of Helsinki in Finland who analyzed 378 children born in 1998. They evaluated the impact of glycyrrhizin — the active ingredient in licorice — against psychiatric and developmental issues during childhood to reach their findings.
The team started by gathering data on the glycyrrhizin intake of the children’s mothers during pregnancy. Under 249 milligrams per week was defined as low intake while 500 milligrams of glycyrrhizin was defined as high intake. In other words, 250 grams of licorice.
The results revealed that children born to mothers with a high glycyrrhizin intake were more likely to show symptoms of ADHD and did not perform well on intelligence and memory tests compared to children whose mothers had a low glycyrrhizin intake.
Additionally, girls were more likely to begin puberty earlier if their mothers consumed high amounts of glycyrrhizin while pregnant.
In a comment on their findings, the researchers say licorice consumption during pregnancy may be associated with harm for the developing offspring. While more research is needed, their findings suggest expectant mothers should be careful when consuming products containing glycyrrhizin, and be aware of the possible outcomes.
Though licorice has long been praised for medicinal benefits like peptic ulcer and canker sore relief, this is not the first instance where licorice has been linked to health issues. A previous study found that glycyrrhizin impacted fetal brain development by inhibiting the enzyme that disables cortisol. Results showed mothers who consumed large amounts of licorice while pregnant were more likely to have children with behavioral issues, such as aggression.
Other recent studies also indicate the candy has negative effects on fertility and fetal development.
For example, a study reported by Medical News Today in 2016 links licorice consumption to reduced fertility in women. Other studies have also suggested that eating licorice during pregnancy can lead to undesirable birth outcomes like low birth weight.
While licorice is not as popular in the United States as it is in Finland, it’s not difficult to unknowingly consume large amounts of glycyrrhizin. It is commonly used as a low-calorie sweetener and a flavor agent in products such as gum, alcoholic and non-alcoholic beverages, and herbal teas and remedies. Daily intake could easily exceed 215 milligrams — even without consuming candy.