For centuries, the root of the Glycyrrhiza glabra plant has been utilized in traditional medicine, not just for its sweet taste but for its purported therapeutic properties. However, the key to understanding its health impact lies in its primary active compound, glycyrrhizin. This component, while responsible for many of licorice's sweetening and medicinal effects, also carries the risk of adverse side effects, such as elevated blood pressure, especially when consumed in high doses or for extended periods. This has led to the development of deglycyrrhizinated licorice (DGL), which removes the majority of this compound. Below, we explore the specific health claims and the scientific evidence supporting them.
Potential Health Benefits of Licorice Root
Digestive Health Support
Licorice root is perhaps most well-known for its positive effects on the gastrointestinal tract. Several studies highlight its ability to soothe and protect the stomach lining.
- Relief from Acid Reflux and Indigestion: Clinical trials have found that supplementing with licorice root can be more effective than standard antacids over a two-year period in reducing symptoms of GERD, such as heartburn and indigestion. For this purpose, DGL is often recommended to mitigate the risks of glycyrrhizin.
- Fighting Peptic Ulcers: Research indicates that licorice, and specifically its flavonoids, may help treat peptic ulcers by inhibiting the growth of the H. pylori bacteria, a common cause of these ulcers. By increasing mucus production and improving blood supply to the stomach lining, licorice helps promote healing.
- Alleviating Functional Dyspepsia: A study found that licorice extract significantly improved symptoms of functional dyspepsia (chronic discomfort in the upper abdomen) after 30 days of use compared to a placebo.
Respiratory and Oral Health
Licorice root has long been used to address issues related to the respiratory tract due to its anti-inflammatory and expectorant properties.
- Soothing Coughs and Sore Throats: As an expectorant, licorice helps loosen and expel mucus from the respiratory system, while its soothing effects calm irritation. It is a common ingredient in many herbal teas and lozenges for this purpose.
- Potential Against Asthma and Bronchitis: Though more human research is needed, animal studies suggest that the anti-inflammatory effects of compounds like glycyrrhizin may help relieve asthma symptoms.
- Dental Cavity Protection: The antimicrobial properties of licorice extract may help protect against dental cavities. One study on preschoolers showed a reduction in the cavity-causing bacteria Streptococcus mutans after using licorice-infused lollipops.
- Canker Sore and Gingivitis Relief: Licorice's antimicrobial properties can also help combat bacteria linked to canker sores and gingivitis.
Benefits for Skin Health
When applied topically, licorice extract can offer several dermatological benefits.
- Reducing Hyperpigmentation: The compound glabridin in licorice extract is known to inhibit tyrosinase, a key enzyme involved in melanin production. This effect helps in reducing hyperpigmentation and brightening the skin.
- Easing Skin Inflammation: Licorice's anti-inflammatory properties make it beneficial for skin conditions like eczema and psoriasis, helping to soothe redness and irritation.
Other Potential Benefits
Preliminary research suggests licorice may also offer benefits for other conditions, though more conclusive evidence is needed:
- Hepatitis C: In Japan, injectable glycyrrhizin has been used to manage chronic hepatitis C that has not responded to other treatments.
- Weight Management: Some studies suggest that licorice flavonoids may help reduce body fat accumulation, though the effect can vary based on dosage and the individual.
- Menopausal Symptoms: Phytoestrogen compounds in licorice may help reduce the frequency and severity of hot flashes.
Licorice vs. Deglycyrrhizinated Licorice (DGL)
| Feature | Standard Licorice | Deglycyrrhizinated Licorice (DGL) |
|---|---|---|
| Active Compound | Contains glycyrrhizin | Has most glycyrrhizin removed |
| Sweetness | Very sweet due to glycyrrhizin | Less sweet, may contain other natural sweeteners |
| Glycyrrhizin Risks | High risk of side effects like hypertension, hypokalemia, and fluid retention with excessive consumption. | Minimal risk of glycyrrhizin-related side effects. |
| Therapeutic Use | Traditionally used for a wide range of ailments, but use is limited by glycyrrhizin risks. | Preferred for addressing digestive issues like GERD and ulcers due to safety profile. |
Important Safety Precautions
Despite its benefits, licorice is not without risk. The consumption of large amounts of glycyrrhizin can lead to a condition known as "apparent mineralocorticoid excess," which mimics the effects of excess aldosterone and can cause:
- High blood pressure
- Low potassium levels (hypokalemia)
- Fluid retention and edema
For most healthy individuals, moderate consumption of licorice as a food flavoring is unlikely to cause serious problems. However, the FDA warns that consuming more than 2 ounces of genuine licorice daily for two weeks or more can lead to heart rhythm problems for those over 40.
- Who Should Avoid Licorice? Individuals with heart disease, high blood pressure, kidney disease, or low potassium should steer clear of licorice containing glycyrrhizin.
- Pregnancy and Breastfeeding: Pregnant women should avoid licorice, as excessive consumption has been linked to an increased risk of premature birth. Its safety during breastfeeding is not well-established.
- Drug Interactions: Licorice can interact with certain medications, including blood thinners (like warfarin), blood pressure drugs, diuretics, and corticosteroids. Always consult a healthcare provider before using licorice supplements, especially if you are on medication.
Conclusion
Licorice root possesses a rich history of medicinal use, and modern science continues to explore its potential benefits. Its potent antioxidant, anti-inflammatory, and antimicrobial properties suggest real therapeutic applications for conditions affecting the digestive system, respiratory tract, and skin. However, the dual nature of its main active compound, glycyrrhizin, necessitates a cautious approach. For many applications, particularly digestive issues, deglycyrrhizinated licorice (DGL) offers a safer alternative by removing the component linked to serious side effects. As with any herbal supplement, moderation is key, and it is crucial to consult a healthcare professional to ensure safety, especially for individuals with pre-existing health conditions or those taking other medications.
