Black liquorice, or licorice, comes from the liquorice plant, and can be drunk as a tea or eaten as a sweet. Licorice can raise blood pressure levels.
The health benefits of black liquorice, also spelt licorice, have been known for centuries in the Middle East, Asia and Greece where it was used for medicinal purposes and as a flavoring additive. The liquorice plant, or licorice plant, is actually a shrub called Glycyrrhiza glabra, and liquorice is harvested from its root. Licorice comes in many forms and can be drunk in the form of liquroice tea or, more commonly, eaten as a sweet or candy. Black liquorice contains glycyrrhizin which is 50 times as sweet as refined sugar. It can however, raise blood pressure.
Black Liquorice Benefits
The benefits of licorice are numerous. For a start, it can help reduce LDL cholesterol levels by making them more resistant to oxidation and increasing bile flow, which in turn can help lower cholesterol levels. The glycyrrhizinic acid found in the licorice plant has antibacterial and antiviral properties as it can help trigger interferon in the body, which helps fight off viral infections. Licorice also contains antidepressant compounds, and can be used topically to treat skin diseases such as eczema, psoriasis and dermatitis. Licorice works in a similar way to hydrocortisone, but without any nasty side effects.
Other uses of licorice include adrenal gland support – a compound in the licorice plant can help block the breakdown of cortisol, to raise cortisol levels, and help the body fight stress. It also has mild estrogenic effects, so may be helpful for women going through the menopause, by helping to balance estrogen levels. Asthma, bronchitis and other respiratory problems can be eased by the use of licorice.
Liquorice Side Effects and Blood Pressure
Licorice contains a substance called glycyrrhizin, which has been known to elevate blood pressure. For this reason a form called deglycyrrhizinated licorice is often preferred as it has no side effects. Licorice has the potential to raise blood pressure and may also cause some water and sodium retention, along with a loss of potassium.
Taking licorice supplements on a long-term basis may not be the best plan. It is also not recommended for anyone who is pregnant, has liver or kidney disease, heart disease, high blood pressure or fluid retention. Those on prescription drugs should take particular care, as licorice may increase drug absorption.
- J Ethnopharmacol. 2007 Apr 4;110(3):563-6. Epub 2006 Oct 20. Glabrol, an acyl-coenzyme A: cholesterol acyltransferase inhibitor from licorice roots. Choi JH, et al
- Ann Med. 2010 Sep;42(6):465-74. Licorice-induced hypertension and common variants of genes regulating renal sodium reabsorption. Miettinen HE, et al