A new study from Linköping University in Sweden has found that even small amounts of licorice can raise blood pressure. This challenges the earlier belief that moderate amounts were safe.
While many people enjoy licorice for its sweet and salty taste, this research shows it might be more harmful than we thought.
Licorice is made from the root of a plant called Glycyrrhiza. It has been used for hundreds of years in traditional medicine and as a flavor in food and drinks. Its strong sweetness comes from a natural substance called glycyrrhizic acid.
But glycyrrhizic acid can affect how the body controls its fluid levels. When this balance is off, blood pressure can go up. High blood pressure increases the risk of heart problems, such as heart attacks and strokes.
Health organizations like the European Union and the World Health Organization have said that most people can safely consume up to 100 milligrams of glycyrrhizic acid per day. However, studies have shown that about 5% of people in Sweden eat more than this amount regularly. That raises concern about possible health risks.
To test whether 100 milligrams is really safe, researchers studied 28 healthy adults aged 18 to 30. They split them into two groups. One group ate licorice with 100 milligrams of glycyrrhizic acid. The other group ate a salty product made with salmiak, which tastes like licorice but does not have the same sweet compound.
After two weeks, the groups switched. This allowed the researchers to see how each person responded to both products.
During the study, participants measured their own blood pressure every day. The researchers also looked at hormone levels, salt balance, and heart health markers.
The results showed that even the “safe” amount of licorice caused blood pressure to rise by an average of 3.1 mmHg. They also found lower levels of two important hormones—renin and aldosterone—that help control salt and fluid balance in the body.
Some people reacted more strongly. They held onto extra fluid, gained a little weight, and showed signs of stress on the heart. This stress was seen through higher levels of a substance called NT-proBNP, which is often found when the heart is working harder than normal.
This study shows that even small amounts of licorice may not be safe for everyone. A small rise in blood pressure might not be serious for healthy people, but it could be dangerous for those with high blood pressure or heart disease.
Another issue is that many licorice products don’t say how much glycyrrhizic acid they contain. Without clear labels, it’s hard to know how much you’re eating, and it’s easy to go over the limit without realizing it.
This research is a reminder that food can have strong effects on our health. Licorice is just one example. Scientists are also studying how other common foods, like potatoes and vegetables high in potassium, can affect blood pressure.
For now, if you are concerned about your heart or blood pressure, it may be a good idea to limit how much licorice you eat or drink. Even a little might be more powerful than you think.
If you care about high blood pressure, please read studies about unhealthy habits that may increase high blood pressure risk, and drinking green tea could help lower blood pressure.
For more information about high blood pressure, please see recent studies about what to eat or to avoid for high blood pressure, and 12 foods that lower blood pressure.
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