New research from Finland has confirmed that women should avoid consuming large quantities of licorice during pregnancy, however, the limit for safe consumption is still unknown.
The study defined a large amount as exceeding 500 mg of glycyrrhizin per week, the main constituent of licorice, and little or no licorice as being less than 249 mg glycyrrhizin per week. A total of 500 mg of glycyrrhizin corresponds on average to 250 g of licorice.
Glycyrrhizin is already known to cause higher blood pressure and shorter pregnancies, however previous studies have not shown long-term effects on the fetus so far. To examine these long-term effects, participants were asked to complete cognitive reasoning tests done by a psychologist.

The team found that children who were exposed to large amounts of licorice in the womb had lower results than those exposed to smaller amounts or no licorice – a difference equivalent to about seven points of IQ. Children exposed to high levels of licorice also showed lower test results in the tasks of measuring memory capacity. Parents reported that these children showed more ADHD-like problems than others, and during teenage adolescence, there were early signs of puberty.

Find out what the results of this research already imply in Finland and all its explanations:

In Finland, the National Institute for Health and Welfare already places licorice in the “not recommended” category for pregnant women, but at the same time asserts that the occasional consumption of small quantities of licorice, in the form of liquorice ice cream or some liquorice candy, does not pose any danger.

Researchers now advise that pregnant women and those planning to become pregnant should be made aware of the harmful effects that products containing glycyrrhizin, such as licorice and salty licorice, can have on their future children.

GLYCYRRHIZINE, DANGEROUS DURING PREGNANCY:
In the body, glycyrrhizin blocks the activity of an enzyme that helps protect the fetus from high levels of cortisol, which is sometimes called the stress hormone. High levels of cortisol can affect the neurological development of a fetus, as described by Finnish researchers.

Normally, this enzyme works by converting cortisol to its inactive form, called cortisone, before passing through the placenta to the fetus. In a previous laboratory study, the same group of researchers found that very low doses of glycyrrhizin effectively blocked this enzyme, allowing cortisol to cross the placenta.

The researchers noted, however, that they could not determine in the study a specific threshold for safe licorice, or whether there was a specific time during pregnancy that women should avoid these candies.

The study warns, however, that licorice may not be the only factor in the study that affected development. It is possible that other unmeasured factors also played a determining role.