Licorice is mostly associated with candy and has been used in food and medicine for 1000 years. It contains various compounds that help with heartburn, cancer, and a leaky gut. Keep reading to learn more about its health benefits.
- The Licorice that I Recommend
- Constituents of Licorice and their Pharmacokinetics
- Deglycyrrhizinated Licorice (DGL) vs Regular Licorice
- Health Benefits of Licorice
- 1) Licorice Is Anti-inflammatory
- 2) Licorice Helps Prevent Heart Disease
- 3) Licorice Protects the Brain
- 4) Licorice May Help Prevent Cancer Growth
- 5) Licorice Benefits the Gut
- 6) Licorice Helps Improve Women’s Health
- 7) Licorice Helps Prevent the Growth of Microbes
- 8) Licorice Prevents Fatigue
- 9) Licorice Helps You Sleep
- 10) Licorice May Benefit Male Infertility
- Side Effects of Licorice Intake
- Buy Licorice
Licorice is a plant native to southern Europe and Asia and is used to flavor candies, sweeteners, and tobacco products.
Licorice contains glycyrrhizin and glabridin, which have proven health effects on the body. It has been used in herbal and folk medicines for its anti-inflammatory properties.
While licorice is mainly found to have positive health benefits, excessive intake of glycyrrhizin may increase high blood pressure and muscle weakness.
The Licorice that I Recommend
Constituents of Licorice and their Pharmacokinetics
1) Glycyrrhizin/ Glycyrrhetinic Acid
After oral ingestion of licorice, bacteria in the body changes glycyrrhizin’s main constituent, glycyrrhizic acid, into glycyrrhetinic acid. Glycyrrhetinic acid is a very potent inhibitor of the 11-ß-HSD enzyme (R).
Carrier molecules absorb and transport glycyrrhetinic acid to the liver, where it is metabolized to different conjugates. It then circulates in the blood and the intestines. Repeated intake of licorice might lead to the accumulation of glycyrrhetinic acid and can cause toxicity (R).
In one human study, glycyrrhizin administration by itself has a lower intestinal absorption rate when it is a component of licorice root extract in comparison to when it is administered alone (R).
In both female and male subjects, daily 300-1200 mg licorice flavonoid oil (LFO) administration showed nearly linear pharmacokinetics. Glabridin levels reach steady state levels around 2 weeks of LFO dosage (R).
LicoA stops inflammation in humans and cell culture by suppressing the lipopolysaccharide (LPS) signaling pathway. It also prevents cancer by suppressing the Akt/mTOR and ERK1/2/p90RSK signaling pathways (R).
4) Isoliquiritigenin and Liquiritigenin
Isoliquiritigenin is a chalcone that has antioxidative, anti-inflammatory, and antitumor effects. In rats, its pharmacokinetics are not dose dependent. Its affinity is high in the liver, kidneys, and small and large intestines (R).
Liquiritigenin is a metabolite of isoliquiritigenin. There are no studies of liquiritigenin pharmacokinetics in humans available. However, scientists have used studies done on mice, rats, rabbits, and dogs to estimate some results (R).
In human cell culture, glabrene activates the expression of estrogen-regulated genes. In rats, glabrene causes a significant increase in creatine kinase activity. Glabrene can mimic estrogen and its beneficial effects in bone and heart tissues (R).
7) Other Compounds
- Formononetin (R)
- Glisoflavone (R)
- Hispaglabridins A and B (R)
- Rutin (R)
- Isoangustone A (R)
- Prunetin (R)
- Dehydroglyasperin C (R)
Deglycyrrhizinated Licorice (DGL) vs Regular Licorice
Health Benefits of Licorice
1) Licorice Is Anti-inflammatory
In an analysis of 93 papers, licorice extract was observed to have anti-inflammatory activities (R).
Lipopolysaccharide (LPS) activity, TNF-α production, and NF-kB activity all lead to inflammation in the brain. Treatment with dehydroglyasperin C (a licorice flavonoid) stops the pro-inflammatory activity and helps prevent neuron cell death (R).
2) Licorice Helps Prevent Heart Disease
3) Licorice Protects the Brain
In stroke-induced rats, glabridin injection (at 25mg/kg) significantly decreased brain damage, prevented nerve cell death, and lowered DNA damage. It also increased antioxidant levels in the brain (R).
Licorice flavonoids can also prevent oxidative damage in the brain. Its antioxidant effects help decrease seizure-induced brain cell death in mice (R).
Oral glabridin administration at 25 and 50 mg/kg reversed learning and memory deficits in diabetic rats. Additionally, it helped improve brain function in non-diabetic rats (R).
Treatment with dehydroglyasperin C (a licorice flavonoid) stops lipopolysaccharide (LPS) activity in mice cell culture. It prevented LPS from inducing TNF-α production. It also reduced NF-kB activity, which helps stop neuron cell death and inflammation (R).
4) Licorice May Help Prevent Cancer Growth
In a human cancer cell line, licorice increased tumor-specific cytotoxicity (R).
In an oral cancer cell line, a polysaccharide from licorice prevents oral cancer cells from growing (R).
Angiogenesis, or blood vessel formation, can become abnormal during the production of tumors. Licohalcone A (LicoA), the main active compound from Glycyrrhiza inflate (licorice), inhibits tumor angiogenesis (R).
The VEGF signaling pathway helps control angiogenesis. LicoA blocks VEGF signaling and the expression of its primary receptor. Thus, LicoA was able to stop blood vessel formation in both human skin cell culture and mice (R).
5) Licorice Benefits the Gut
Also, licorice may be able to treat drug poisoning by increasing metabolizing enzymes and other mechanisms (R).
6) Licorice Helps Improve Women’s Health
Glabridin and glabrene, both licorice flavonoids, have estrogen-like activities. This can help women who have low estrogen levels (R).
Glabridin has a similar effect on human cell culture as estradiol-17beta (a form of estrogen). It was able to stimulate the DNA synthesis and formation of certain cells. Like estradiol-17beta, it also blocked creatine kinase activity (R).
On the other hand, glabrene can bind to estrogen receptors and also stimulate muscle cell formation (R).
The glycyrrhetinic acid from licorice can reduce testosterone levels while inducing regular ovulation. Two other licorice metabolites (glabridin and glabrene) have estrogen-life effects that can help treat PCOS (R).
In menopausal women, licorice is more effective than hormone replacement therapy (HRT) by reducing hot flash duration, but not hot flash severity (R).
7) Licorice Helps Prevent the Growth of Microbes
Licorice stimulates the immune system and has antioxidant properties (R).
Licorice has antiviral and antimicrobial properties by preventing virus gene replication and stopping bacterial gene expression (R).
8) Licorice Prevents Fatigue
Glabridin, a polyphenolic flavonoid from licorice extract, prevented fatigue in mice. Mice treated with glabridin swam for a longer period of time compared to control mice. The larger the dose of glabridin, the longer the exercise period lasted (R).
High blood lactic acid levels are a good indicator of fatigue. Exercising mice treated with glabridin had significantly lower blood lactic acid levels in comparison to the control group. Glabridin can slow down and lower the amount of blood lactic acid produced after exercise (R).
However, clinical trials are needed to determine glabridin’s effects on humans.
9) Licorice Helps You Sleep
The GABA-BZD receptor is an important target for inducing sleep. Licorice ethanol extract induces sleep in mice via the GABA receptor. This decreased the time required to fall asleep and increased the length of non-REM sleep (R).
10) Licorice May Benefit Male Infertility
Side Effects of Licorice Intake
Although licorice may have its benefits, chronic or excess consumption can cause unwanted complications and health problems. Since these effects mostly come from glycyrrhizic acid, DGL can help avoid these side effects (R).
1) Licorice Increases Cortisol Levels
In large doses, licorice can increase cortisol levels.
Glycyrrhizic acid and glycyrrhetinic acid, active metabolites (products of metabolism) of licorice extract, act like aldosterone. It inhibits the 11β-hydroxysteroid dehydrogenase type 2 (11β-HSD2) enzyme and stops it from converting cortisol to cortisone. This causes an increase in cortisol half-life and an increase in cortisol activity (R, R).
A longer half-life for cortisol means that it takes longer for the concentration of cortisol in the blood to decrease. Excess cortisol can cause hypertension (high blood pressure). These effects from glycyrrhizic acid are greater in women than in men (R, R).
The increase in cortisol can also cause pseudo-hyperaldosteronism. This condition is characterized by elevated blood pressure, decreased blood potassium concentration, and the retention of water and sodium (R, R).
The hypothalamic–pituitary–adrenal (HPA) axis is an important response system to stress. Normal cortisol levels help maintain the HPA axis. However, excess cortisol can cause HPA axis dysfunction and lead to chronic stress, depression, alcoholism, and other disorders (R).
The inactivation of 11β-HSD2 can cause HPA axis dysfunction. In one review, pregnant women who consumed licorice had lower placental 11β-HSD2 levels. Their children had behavioral problems associated with HPA axis dysfunction (R).
2) Licorice Slows Down Drug Metabolism
Multiple components of licorice, including liquiritigenin and isoliquiritigenin, inhibit the CYP3A4 gene and cytochrome P450 enzymes. Inactivation of P450 enzymes could also slow down drug metabolism, enhance their concentration in the blood, and increase the risk of drug side effects (R).
3) Excess Licorice Consumption Can Lower Potassium Levels
When licorice metabolites inhibit the 11-βHSD2 enzyme, it also causes excess mineralocorticoid production and a decrease in potassium levels. In multiple case studies, excess licorice consumption caused hypokalemia (low potassium) and muscle weakness (R).
Still, this effect seems to vary among patients. The full effect of licorice on potassium depends on the person’s health, the medication they are taking, and other factors (R).
4) Licorice Can Cause Problems During Pregnancy
In a survey of Finnish women who gave birth to premature babies, heavy licorice consumption was significantly associated with a shorter pregnancy term. The glycyrrhizic acid from licorice increases cortisol levels, which can cause an increase in prostaglandin levels in the uterus. This may lead to contractions (R).
However, these results may not necessarily be caused solely by licorice consumption. Because this information was collected retrospectively, other factors may have caused premature delivery (R).
In one review, women who consumed licorice during pregnancy had children with behavioral problems associated with HPA axis dysfunction (R).
5) Other Rare Side Effects
Some rare side effects include heart attack and stroke, but not many studies have shown these results (R).
- Glycyrrhetic acid can also bind to mineralocorticoid receptors, but its affinity is less than that of aldosterone (R).
- LicoA binds with PI3K and MEK1, as well as B-Raf, to suppress COX-2 enzyme expression (R).
- Liquiritigenin, isoliquiritigenin, glycycoumarin, semilicoisoflavone B, licoisoflavone A, licoricone, glycyrol, licoflavonol, and licoisoflavone B may be the key compounds responsible for licorice–P450 interactions (R).