I once made a call to an acquaintance. She asked me to listen carefully; she had just stopped blood pressure medication. And yes, I should say that I’m really intrigued by issues related to hypertension treatment. She reiterated her story like this.
Case 1: Lack of usual dose of salted liquorice resulted in collapse
“We had a two-week vacation in Thailand over two months ago. I took antihypertensives along with me, but did not take salted liquorice. Therefore, I was about to start a two-week detox from liquorice. The holidays went quite well and the abstinence from liquorice did not seem to be a botheration. When we arrived back to Finland, we decided to dodge all sweets for some time, as our intention was to lose weight and improve fitness. Thus, detox from liquorice naturally continued for more than two weeks. My health began to deteriorate oddly; I was dizzy and somehow felt a bit confused.
Once I was on the verge of fainting when I was in the shower. My husband insisted that I check my blood pressure with a home device. My pressure was 80/58 mm Hg! My blood pressure was half of what it was when I started taking antihypertensives a couple of years ago. No wonder why I felt awful. On medication, my blood pressure was often around 140/85 mm Hg and the body had assimilated to that level over the years. Extremely low blood pressure compared to my usual pressure made me feel extremely ill. We realized only then that the low blood pressure could be due to complete liquorice abstinence.
I went to the doctor and we decided to stop blood pressure medication and continue liquorice abstinence. As a result, my blood pressure settled at 120-130/80 mm Hg without medications. And I had a great feeling.”
Case 2: Salted liquorice restores normal well-being
Earlier this spring, I was introduced to a man of my age. He told me about his own salted liquorice experience after learning about my background.
The man had fallen ill about a year ago and had Addison’s disease. Addison’s disease is a chronic and serious condition in which cortisol secretion is reduced. Disease diagnosis was delayed for months and the man had long suffered from severe symptoms. Blood pressure was low, less than 100/70 mm Hg continuously. Since the diagnosis of the disease had been delayed for various reasons, the man found that eating plenty of salted liquorice could improve his condition. He had not checked his blood pressure, but had found that eating liquorice on a regular basis significantly improved his health and ameliorated dizziness and sickness. Eventually, a specialist made a correct diagnosis and gave him a replacement cortisol, asking him to stop excessive eating of liquorice.
The background of the cases
In both cases, the common denominator is glycyrrhizic acid. It inhibits the metabolism of cortisol to inactive substances. Thus, glycyrrhizic acid increases the blood’s cortisol levels (Walker 1994). In Case 1, glycyrrhizic acid of liquorice prevented the normal breakdown of cortisol which resulted in excess of cortisol. In Case 2, Addison’s disease caused lack of cortisol that was partly ‘treated’ with glycyrrhizic acid. It inhibited cortisol breakdown and helped in maintaining almost normal blood levels of cortisol.
Liquorice, salted liquorice, many sweets, drinks and chewing gums contain liquorice extract. Liquorice extract is the source of glycyrrhizic acid. In the same manner that some people are salt-sensitive, some people are more prone to the effects of liquorice than others. Some people are so sensitive that taking small amounts of liquorice once in every two weeks or so is sufficient to keep their blood pressure elevated.
Doctors who have specialized in hypertension know all about these effects and take liquorice anamnesis continuously. Most of the doctors are not well-versed about the effects of salted liquorice and have false notions that doses of liquorice need to be very high to achieve deleterious effects. In the updated version of the Finnish Käypä Hoito guidelines for hypertension treatment, liquorice has been discussed in detail and recommendations have been made to cease liquorice consumption in hypertension.
Is liquorice harmful to the fetus?
The harmful effects of glycyrrhizic acid are of course linked to the excessive cortisol levels in the blood. Cortisol is a stress hormone that is secreted early in the morning and in stressful situations. Cortisol may cause swelling (fluid collection), increased appetite, osteoporosis and hypokalemia. The risk of hypokalemia is particularly high with co-use diuretic medication, such as in congestive heart failure (Hukkanen et al 2009). Elderly patients may be particularly susceptible to hypokalemia.
Regarding the effects of liquorice on pregnancy and the health of offsprings, a couple of alarming papers have been published. The Finnish research team has released three different studies, all of which have observed that consumption of liquorice during pregnancy caused problems for the fetus. Although these studies are non-randomized studies, the results are of huge concern. Even moderate, and especially high, liquorice consumption can have the following complications:
- Increases the risk of preterm delivery (Strandberg et al. 2002)
- Causes behavioral symptoms in children,ADHD-like syndrome (Räikkönen et al 2009)
- Exposes children to a continuous and very high basal secretion of cortisol (Räikkönen et al. 2010)
Although the above data on pediatric population are mainly retrospective studies, they provide sufficient reason to avoid liquorice during pregnancy in the same manner as energy drinks are to be avoided (because of their high caffeine content). Energy drinks carry a warning label about caffeine, but liquorice products do not mention glycyrrhizic acid.
Glycyrrhizic acid has shown to also affect one of the key enzymes of drug metabolism CYP3A4. CYP3A4 is induced by glycyrrhizic acid (Tu et al. 2010). Thus, high liquorice intake may accelerate drug metabolism and make drugs using the 3A4 pathway ineffective. This has been demonstrated with at least omeprazole which is partly metabolized by CYP3A4 (Tu et al. 2010).
Men might be interested in knowing the fact that glycyrrhizic acid could reduce testosterone levels in the blood by 25-50 % (Armanini et al. 2002). This effect was also observed in women (Armanini et al. 2004).
Some of the drawbacks of liquorice, particularly stomach problems, may be related to liquorice ammonium chloride. It is toxic at high concentrations and apparently causes headache, vomiting and nausea. However, these effects are not adequately documented in medical literature.
Every cloud has a silver lining
Yes, liquorice has also some health benefits, at least in theory. They include for example, the inhibition of the growth of viruses, fat mass reduction, cancer cell growth retardation, as well as gastric mucosal protection. Because the disadvantages outweigh the benefits, it may seem that research has not progressed significantly in these fields. Most of the studies so far have been done in animals and in vitro.
List of food and drinks containing glycyrrhizic acid
Salted liquorice is especially popular in Nordic countries and in Holland. However, liquorice is abundant all over the globe. Manufacturers of food items do not need to claim the presence of glycyrrhizic acid on labels. Thus, the way to track down glycyrrhizic acid is to look for liquorice extract in labels of food items. Liquorice extract is used very widely in the confectionery industry. The following products contain glycyrrhizic acid:
- Salted liquorice (”salmiak” in Nordic countries)
- Ice cream including liquorice flavour
- Liquorice flavoured tea (often known as Orient)
- Liquorice flavoured vodkas (Turkish pepper, etc.)
- Pastis and other anis containing alcohol drinks
- Liquorice flavoured chewing gum
- Liquorice flavoured snuff (allowed in the European Union only in Sweden)
- Tar flavoured sweets
- Some fruit gum (check the label for liquorice extract)
- Some herbal products and alternative medicines (check the label for liquorice extract/root)
Healthcare professionals take liquorice anamnesis! Healthcare providers should be familiar with liquorice-related health problems. Interactions with drugs, especially diuretics, and CYP3A4 metabolised drugs will further confirm the notion that liquorice is not good for the heart and cardiovascular patients. In addition, the early results of the Finnish researchers regarding the effects of liquorice on children give a rise for concern.
Those who treat pregnant women and heart patients should be aware of caveats of liquorice extract and educate their patients on the limitations. When the individual response of glycyrrhizic acid is so different, no safe dose can be determined. The best thing is probably to totally avoid liquorice during pregnancy and in cardiovascular disease.