Scientists from University of Rochester have reported potential health risks associated with consuming excessive amounts of black licorice.
Licorice root contains glycyrrhizin, a natural compound that can cause harmful side effects when consumed in large quantities.
Recent research suggests that glycyrrhizin can mimic the effects of the hormone aldosterone, leading to elevated blood pressure and disturbances in heart rhythm.
The study describes a case involving a woman who developed serious health problems after excessive licorice intake.
Licorice is an herb native to parts of Europe and Asia. Its root contains glycyrrhizin, which can have adverse effects on the body when consumed in excess.
Glycyrrhizin mimics aldosterone, a hormone produced by the adrenal glands that helps regulate sodium retention and potassium excretion. High levels of glycyrrhizin can raise blood pressure and disrupt normal heart rhythm. Other symptoms of excessive licorice consumption may include swelling, muscle pain, numbness, and headaches.
A 50-year-old woman sought medical attention after experiencing muscle aches and dark-colored urine for four days. She was taking a diuretic, commonly known as a “water pill,” to increase urine output and reduce excess fluid in the body.
During the medical evaluation, the patient reported consuming approximately one and a half bags of black licorice bites containing 2% natural licorice over a three-week period. Laboratory tests revealed high blood pressure, elevated markers of muscle injury, and abnormally low levels of potassium, calcium, and phosphorus.
Potassium is essential for normal nerve and muscle cell function, particularly in heart muscle cells. Calcium plays a key role in electrical signal transmission throughout the body, while phosphorus is involved in multiple metabolic processes.
Deficiencies in these minerals can lead to muscle weakness, respiratory or cardiac failure, seizures, or even coma.
Glycyrrhizic acid and cortisol
The researchers found that glycyrrhizic acid—the active compound derived from glycyrrhizin—inhibits an enzyme responsible for converting cortisol, a steroid hormone, into its less active form, cortisone.
As a result, cortisol levels can rise abnormally, producing effects similar to a condition known as apparent mineralocorticoid excess (AME). AME is characterized by high blood pressure and low levels of potassium, calcium, and phosphorus.
In this case, excessive licorice consumption led to severe potassium depletion, triggering a life-threatening condition called rhabdomyolysis, which involves the breakdown of skeletal muscle tissue.
The researchers also suggest that licorice intake may have contributed to the patient’s low phosphorus levels, further worsening her condition. They caution against excessive consumption of black licorice and emphasize the importance of moderation.
The study highlights the serious health risks that can arise from consuming large amounts of black licorice. Glycyrrhizic acid can disrupt hormone balance, raise blood pressure, alter mineral levels, and lead to severe complications.
The researchers stress that individuals should be mindful of their licorice intake and avoid excessive consumption. Awareness of these risks may help people make safer dietary choices.
The research, conducted by Megha Shah and colleagues, was published in Clinical Nephrology.
