Individuals should avoid drinking licorice root tea during pregnancy. This caution stems from a specific compound in the root of the Glycyrrhiza glabra plant, the source of true licorice. While the tea is derived from a natural source, the active chemical components can pose risks to both the pregnant person and the developing fetus.
Glycyrrhizin: The Primary Compound of Concern
The primary bioactive component in licorice root is glycyrrhizin (glycyrrhizic acid), a triterpenoid saponin responsible for the plant’s characteristic sweetness. This substance triggers physiological concerns during pregnancy by inhibiting the enzyme 11-beta-hydroxysteroid dehydrogenase type 2 (11β-HSD2).
This enzyme regulates the body’s stress hormone, cortisol, by converting active cortisol into its inactive form, cortisone. When glycyrrhizin inhibits 11β-HSD2, active cortisol levels increase because the body cannot efficiently deactivate the hormone. In the kidneys, excess cortisol acts on mineralocorticoid receptors, leading to an aldosterone-like effect.
The 11β-HSD2 enzyme is also present in the placenta, forming a protective barrier against high levels of maternal cortisol. Inhibiting this barrier allows a greater amount of maternal cortisol to cross into the fetal circulation. While cortisol is necessary for normal fetal development, excessive exposure is associated with potentially harmful programming effects on the developing fetus.
Documented Health Risks During Gestation
High consumption of licorice products containing glycyrrhizin has been linked to adverse health outcomes for both the mother and the child. For the pregnant individual, the aldosterone-like effect caused by enzyme inhibition can lead to serious cardiovascular concerns. This mechanism results in sodium and water retention, increasing fluid volume and leading to high blood pressure (hypertension).
Another risk is an electrolyte imbalance characterized by low potassium levels (hypokalemia). Hypokalemia can cause symptoms like muscle weakness and, in severe cases, abnormal heart rhythms or congestive heart failure. These maternal risks are concerning during pregnancy, which already involves changes in blood volume and circulation.
Exposure to high doses of glycyrrhizin has also been associated with risks to the fetus and child. Studies suggest a link between high maternal licorice intake (e.g., 250 grams of candy per week) and an increased risk of delivery before 38 weeks of gestation.
Research indicates that children exposed to large amounts of glycyrrhizin in the womb performed less well on cognitive reasoning and memory tests later in life. These findings suggest an impact equivalent to approximately a seven-point drop in IQ scores and a greater likelihood of ADHD-type problems.
Differentiating Licorice Products and Concentrations
Confusion arises because not all licorice-flavored products contain glycyrrhizin. Many candies and flavorings, especially in the United States, use anise oil instead of true licorice root (Glycyrrhiza glabra) for a similar taste profile. Anise oil does not contain glycyrrhizin and does not pose the same health risks. Consumers should check product labels to ensure the flavoring is not derived from Glycyrrhiza glabra root or extract.
The concentration of glycyrrhizin varies significantly across different true licorice products, affecting the level of risk. Standard licorice root tea, a potent infusion of the whole root, can contain a substantial and unregulated amount of the compound. Concentrated extracts, often used in supplements, typically carry the highest risk due to their potency.
Deglycyrrhizinated Licorice (DGL)
A product known as Deglycyrrhizinated Licorice (DGL) is a processed extract where most of the glycyrrhizin has been intentionally removed. This process leaves behind less than three percent of the compound. DGL is a safer alternative for digestive issues, though its use should still be discussed with a healthcare professional during pregnancy.
Safer Herbal Tea Alternatives for Pregnancy
For pregnant individuals seeking a warm beverage or relief from common gestational discomforts, several herbal teas are alternatives to licorice root tea. Ginger tea helps alleviate symptoms of nausea and vomiting, particularly during early pregnancy. It is safe when consumed in moderation and can also aid in digestion.
Peppermint tea is another option that can soothe an upset stomach and relieve digestive issues like flatulence. It is safe for moderate consumption, though it can sometimes exacerbate heartburn, a frequent pregnancy complaint. Raspberry leaf tea is often recommended later in the third trimester to tone the uterus in preparation for labor.