Because 2020 hasn’t provided enough extraordinary ways to die, the universe is offering a grim reminder that eating too much licorice candy can be deadly.
A 54-year-old construction worker recently died in Massachusetts after eating an excessive amount of black licorice, which naturally contains a toxin called glycyrrhizin, also called glycyrrhizic acid. Doctors published a case study of his poisoning in the New England Journal of Medicine this week.
According to the study, the poor guy was at a fast-food restaurant when he went into sudden cardiac arrest. He “suddenly gasped, with whole body trembling and loss of consciousness,” the doctors report. Paramedics arrived within minutes and resuscitated him with four shocks and CPR. But when he was hospitalized about 30 minutes later, doctors found he had multi-organ failure, “deep metabolic disturbances,” dangerously low levels of potassium in his blood, and cardiac arrest associated with ventricular fibrillation, which is when the lower chambers of the heart vibrate irregularly without to pump blood. All of these conditions are consistent with licorice poisoning.
A thorough medical examination revealed that he appeared to have no history of heart problems, and doctors pinned his condition on the candy. Conversations with his family revealed that he had eaten one to two “large” bags of black licorice every day for about three weeks before his heart stopped. By the time he got to the hospital, too much damage had already been done. He died about 32 hours later, with his family at his bedside.
Medical researchers have long known about the complex and toxic effects of the licorice plant on the human body. Licorice has a storied and tortuous history in Eastern and Western cultures, dating back to the Babylonian and Egyptian empires. Hippocrates prescribed it in the treatment of asthma and dry cough. Chinese traditional medicine has used licorice root to treat ailments from tuberculosis to stomach ulcers.
But these applications were not without side effects. In the 1950s, Dutch physician-scientist FE Revers conducted one of the first systematic studies of the anti-ulcer effects of licorice extract and noted that patients experienced swelling, “severe headaches,” high blood pressure, and chest pain and pressure. .
Over the following decades, researchers discovered that the glycyrrhizin in licorice is taken up by microbes in the gut and converted into glycyrrhetinic acid (also called glycyrrhetinic acid). This metabolized version is then absorbed by the body. In the kidneys, glycyrrhetinic acid derivatives inhibit a critical enzyme called 11-hydroxysteroid dehydrogenase type 2, or 11-HSD2, which converts the steroid hormone cortisol to cortisone. Cortisol has many important functions, including a critical regulator of ion, salt and water balance. This, in turn, has a significant impact on blood volume, blood pressure and the overall functioning of the cardiovascular system.
With 11βHSD2 blocked by glycyrrhetinic acid, cortisol levels build up in the kidney. This leads to higher sodium levels, water retention, a drop in potassium levels and a subsequent cascade of life-threatening problems in the body, including kidney failure. The increase in sodium and water retention leads to swelling and high blood pressure. The extreme drop in potassium levels (hypokalemia) disrupts the ionic balance that is critical to the cardiac conduction system — a specialized group of heart muscle cells that use electrical signals to cause the heart muscles to contract and pump blood. As such, drops in potassium levels can lead to fatal irregular heart rhythms, such as ventricular fibrillation.
Scary but rare
To make matters worse, glycyrrhetinic acid also interferes with enzymes in the liver that affect levels of aldosterone, another crucial steroid hormone, which exacerbates all of the toxin’s other health effects. The liver also recycles glycyrrhetinic acid, which means that high levels can build up after frequent licorice consumption and remain high for a long time. It can take weeks for the symptoms of licorice poisoning to disappear.
For these reasons, medical researchers and health authorities warn against eating a lot of black licorice – all at once and/or on a daily basis. In fact, the U.S. Food and Drug Administration typically likes to remind consumers of the life-threatening risk around Halloween every year (although sadly that’s not necessary this year).
In previous warnings, the FDA notes, “If you are 40 or older, eating 2 ounces of black licorice a day for at least two weeks could land you in the hospital with an irregular heart rhythm or arrhythmia.”
Still, because black licorice is not a very popular candy and few people indulge in toxic enough amounts, the gummy candies pose no threat to public health. (Not all “licorice” candies also contain licorice plant extract, including many red licorice candies, such as red Twizzlers.) Reports of illness are rare, let alone deaths. Some of the few examples of harm include an FDA reference to a “black licorice enthusiast” who “had a problem” after eating the candy in 2016. eating no less than 1.8 kilograms (about 63.5 grams) of black licorice per week and went into cardiac arrest. But she survived the cardiac arrest and made a full recovery after she stopped eating licorice.
The poor fellow in Massachusetts wasn’t so lucky. Although doctors were able to increase his potassium levels with large, intravenous doses of potassium chloride, his condition worsened. His blood pressure became unstable, his neurological prognosis was poor and his kidneys were failing. He was moved to consolation before dying peacefully with his family.