Licorice Root

Safety Status: Avoid Entirely

Licorice root (Glycyrrhiza glabra), black licorice candies containing real licorice extract, and herbal supplements or teas featuring licorice root must be strictly avoided during pregnancy.

While many herbal remedies are assumed to be benign, licorice root contains an active chemical compound called glycyrrhizin that has documented adverse effects on fetal development. Long-term study cohorts have linked high maternal intake of glycyrrhizin to cognitive impairments, behavioral problems in children, and an elevated risk of preterm birth, making this a critical YMYL concern.

The Mechanism of Toxicity: Glycyrrhizin & Cortisol

The toxicity of licorice root on a developing fetus occurs through a specific biological mechanism:

• Inhibition of 11-beta-HSD2: The placenta naturally produces a protective enzyme called 11-beta-hydroxysteroid dehydrogenase type 2 (11-beta-HSD2). Under normal circumstances, this enzyme acts as a barrier, breaking down maternal stress hormones (specifically cortisol) so they do not flood the fetus.
• Maternal Cortisol Exposure: Glycyrrhizin inhibits the activity of the 11-beta-HSD2 enzyme. When this barrier is compromised, high levels of maternal cortisol cross the placenta freely, entering the fetal circulation.
• Fetal Implications: Chronic exposure to excess cortisol during key stages of embryogenesis can disrupt fetal brain development. Long-term studies show that children exposed to high levels of glycyrrhizin in utero have lower cognitive scores, memory deficits, and higher rates of Attention Deficit Hyperactivity Disorder (ADHD) and behavioral issues.
• Preterm Birth: High cortisol levels and the systemic effects of glycyrrhizin (which causes sodium retention and potassium loss in the mother) can trigger maternal hypertension (high blood pressure) and stimulate early labor, increasing the risk of preterm delivery.

Safe Selection and Ingredients Check

To navigate licorice safely:

• Check the Label: Many popular “black licorice” candies sold in supermarkets are actually flavored with anise oil (a plant with a similar sweet, aromatic flavor profile but a different chemical makeup) rather than real licorice extract. If the package lists “anise oil” or “artificial flavor” and contains no “licorice extract” or “glycyrrhizin,” it is safe.
• Avoid Herbal Blends: Carefully inspect the ingredient lists of herbal tea bags (especially those labeled for throat coating, digestion, or detox) and cough remedies. Licorice root is a common ingredient added for sweetness and throat coating, but it should be avoided.
• Avoid DGL Supplements: Deglycyrrhizinated licorice (DGL) is a supplement where glycyrrhizin is removed, often used to treat heartburn. However, because supplement regulation is limited, pregnant individuals should avoid DGL and use standard FDA-approved antacids (like calcium carbonate) for acid reflux.