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Woman drinks three cups of liquorice tea every day

A 48-year-old woman developed high blood pressure due to her love of three cups of liquorice tea each day, a case report reveals.

The unnamed patient, believed to be from Sheffield, was plagued by dull headaches, nausea and dizziness for four months before becoming concerned.

Doctors warned her daily habit for liquorice tea was to blame as it caused her to develop hypertension and low levels of potassium in her blood.

As soon as she stopped drinking so much of the sweet brew, all of her symptoms disappeared, medics wrote in the BMJ Case Reports. 

A 48-year-old woman developed high blood pressure due to her love of three cups of liquorice tea each day, a case report reveals

Upon initial inspection, doctors struggled to find a root cause for her high blood pressure. They sent her home with medication.

However, drugs proved to have no effect and doctors grew increasingly concerned that her condition was worsening rapidly.

That was when the woman realised her headaches, a symptom of hypertension, was likely due to her love of liquorice tea.

She said her husband uncovered the link between liquorice and high blood pressure which made her highlight her habit to the doctors. 

Nine times above the safe limit 

According to the report, the woman was consuming ‘at least nine times above the safe limit’ of glycyrrhizin in her three cups of tea a day.

‘By omitting liquorice tea, the blood pressure normalised and headache resolved,’ wrote doctors at Sheffield Teaching Hospitals NHS Foundation Trust.


Black liquorice is made with extract from root of the Glycyrrhiza glabra plant that gives the candy its sweetness. 

The root contains a compound called glycyrrhizin.

Glycyrrhizic acid keeps the body from properly absorbing potassium, so when you consume too much glycyrrhizin, potassium levels may drop below normal levels.

The balance between potassium and sodium levels is key to healthy heart functioning. 

When potassium levels are too low, sodium levels are correspondingly too high. 

The imbalance can result in high blood pressure and upset the heart’s rhythm.

Abnormal heart rhythms greatly increase the risk of heart attack. 

The patient was eventually allowed home.  

Liquorice tea has long been used to relieve heart burn and constipation – but research to prove its benefits are scarce.

The case serves as a reminder about the dangers of excessive liquorice and backs up repeated warnings over the sweet treat.

Black liquorice contains high levels of glycyrrhizin, which prevents the body from properly absorbing potassium.

When potassium levels drop, sodium levels tend to rocket, which results in high blood pressure and can upset the heart’s rhythm. 

Worrying case studies 

In 1991, a case reported in the New England Journal of Medicine revealed how a man had overdosed from eating too much liquorice.

The 70-year-old, whose identity remains unknown, consumed between 60 and 100 pieces of the sweet treat each day for four years.

Another patient was diagnosed with high blood pressure and low potassium after eating 160 ‘Fisherman’s Friend Extra Strong’ lozenges each day, it was reported. 

The FDA issued a warning in October that eating two ounces (60g) of black liquorice each day can lead to arrhythmia. 

And the UK Food Standard Agency demands liquorice products to carry a warning about excessive consumption for those with high blood pressure.