Liquorice compounds and blood pressure in people
What it found
In people, licorice ingredients high in glycyrrhizic acid raised systolic and diastolic blood pressure, while licorice flavonoids made no clear difference.
The authors also used lab and computer methods to suggest how glycyrrhizic acid might act.
What they found
Studies in people
Glycyrrhizic acid and blood pressure
In people, licorice products with glycyrrhizic acid as the main ingredient raised systolic blood pressure by about 3.48 mmHg and diastolic blood pressure by about 1.27 mmHg on average compared with controls.
Licorice flavonoids and blood pressure
In people, licorice products with flavonoids as the main ingredient showed no clear effect on systolic or diastolic blood pressure.
Dose and duration
In people, taking more than 100 mg of glycyrrhizic acid a day had a bigger effect on systolic blood pressure than 100 mg or less a day. Taking it for 8 weeks or longer had a bigger effect on systolic blood pressure than shorter periods.
Animal and lab studies
Toxicity prediction
A computer tool predicted that glycyrrhizic acid may have heart, kidney and nutritional toxicity, and that it may be poorly absorbed.
Studies in people and animals
Possible mechanism
In lab and computer work, glycyrrhizic acid and its metabolite glycyrrhetinic acid were predicted to bind to three proteins linked to high blood pressure: GFI1B, MYLK and RSU1. These proteins were more active in people with high blood pressure in one dataset.
What the authors conclude
- They conclude that glycyrrhizic acid can raise blood pressure, while licorice flavonoids do not have a significant effect.
- They suggest that people with high blood pressure or those prone to it should be careful about eating foods containing glycyrrhizic acid.
- They call for more high-quality studies on the long-term safety of glycyrrhizic acid and its salts in specific groups.
How it was done
The authors wanted to find out which parts of licorice affect blood pressure, since licorice is widely used in foods and medicines and its effects on blood pressure have been unclear.
They pooled eight randomized controlled trials with 541 participants that tested licorice or its components. They also used computer tools to look at genes and proteins linked to high blood pressure.
What it can’t tell you
- The pooled trials were short and varied in design, so they cannot show the effects of long-term licorice use.
- The lab and computer findings cannot prove that glycyrrhizic acid raises blood pressure through these proteins in people.
- The review cannot show whether licorice flavonoids are safe for everyone, since only a limited number of people were studied.
Who paid
- Funding
- Funded by Guiju Sun (from the PubMed record).
- Conflicts
- The authors declare no conflicts of interest.
- Authors work at
- Southeast University, China
The paper
- Title
- Effects of Licorice Functional Components Intakes on Blood Pressure: A Systematic Review with Meta-Analysis and NETWORK Toxicology
- Type
- Systematic review and meta-analysisThe authors follow a set, published method to find every relevant study, then combine the numbers from them into one result.
- Evidence
- Studies in people · animals · lab
- Summarised from
- Full text
- Licence
- CC BY. Words in quotation marks are the authors’; the rest is our summary.
- Cite
- Wu T, Yang J, Xia J, Sun G (2024). Effects of Licorice Functional Components Intakes on Blood Pressure: A Systematic Review with Meta-Analysis and NETWORK Toxicology. Nutrients. doi:10.3390/nu16213768Free full textPubMed 39519602DOI
Summary written 30 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error