The Dual Nature of Licorice: Sleep Aid or Sleep Disruptor?
Licorice, or Glycyrrhiza glabra, is an ancient herb with a sweet-tasting root that has been used for centuries for various medicinal purposes, including as a digestive aid and for respiratory issues. However, its effect on sleep is not straightforward. The root contains an active compound called glycyrrhizin, which is responsible for many of its health effects, both positive and negative. At bedtime, this compound presents a significant dilemma. While some studies suggest licorice can help regulate sleep cycles by interacting with GABA receptors, its stimulating effects on adrenal hormones and blood pressure can have the opposite effect for many people.
Why Licorice Can Be Bad for Sleep
For most people, the main risk of consuming real licorice before bed comes from its high concentration of glycyrrhizin. This compound can interfere with the enzyme 11β-hydroxysteroid dehydrogenase type 2, leading to higher levels of the stress hormone cortisol in the body. This effect can lead to a condition known as pseudohyperaldosteronism, which is associated with several sleep-disrupting issues:
- Increased Blood Pressure (Hypertension): Higher cortisol levels can cause the body to retain sodium and water, which in turn elevates blood pressure. High blood pressure can cause headaches and anxiety, making it difficult to fall asleep and stay asleep.
- Electrolyte Imbalance (Hypokalemia): Alongside sodium retention, glycyrrhizin promotes potassium excretion. Low potassium levels can cause muscle weakness, lethargy, and heart rhythm abnormalities, all of which are detrimental to sleep.
- Fluid Retention (Edema): The body's retention of salt and water can lead to swelling, causing discomfort that can interfere with rest.
Furthermore, some people find licorice, particularly in supplement form, to be overly stimulating. The effect of modulating adrenal function can sometimes feel like a boost of energy, particularly in the morning, but taking it at night can lead to insomnia.
The Potential Sleep Benefits of Licorice
Despite the risks, licorice is also noted for certain properties that could theoretically aid sleep, primarily in deglycyrrhizinated forms or very small doses. Licorice contains a flavonoid called glabrol, which has been shown to interact with GABA receptors in the brain. GABA is a neurotransmitter that promotes relaxation and rest. Research has also suggested that glycyrrhizin could alleviate insomnia by upregulating GABA levels, though this requires careful dosage to avoid the aforementioned risks. For this reason, some herbal tea blends formulated for sleep include licorice root alongside calming herbs like chamomile. However, this is a delicate balance, and the benefits must be weighed against the potential negative effects.
Types of Licorice: Real vs. DGL
For bedtime consumption, understanding the difference between real licorice and DGL (deglycyrrhizinated licorice) is crucial.
- Real Licorice: Contains glycyrrhizin, the compound responsible for both the unique sweetness and the associated health risks. Found in traditional licorice candy, supplements, and teas.
- DGL Licorice: Has the glycyrrhizin removed, making it a safer option for those sensitive to its effects. DGL is often used to soothe stomach issues without affecting blood pressure. It may not offer the same sleep benefits as glycyrrhizin but is less likely to disrupt sleep.
- Licorice-Flavored Candy: Many products, especially in the US, use anise oil for flavoring instead of real licorice root. These products do not contain glycyrrhizin and are not associated with the same blood pressure risks, but they are often high in sugar, which can negatively impact sleep.
Comparison: Real Licorice vs. DGL Licorice for Sleep
| Feature | Real Licorice (with Glycyrrhizin) | DGL Licorice (Glycyrrhizin removed) |
|---|---|---|
| Effect on Sleep | May promote sleep via GABA or cause insomnia via adrenal stimulation. | Does not contain the compound that promotes sleep or adrenal stimulation. |
| Risks Before Bed | High risk of elevated blood pressure, hypokalemia, and fluid retention. | Very low risk of these side effects. |
| Use Case | Traditional herbal remedy; requires caution, especially at night. | Safer for bedtime use for digestive issues, as it lacks major side effects. |
| Taste Profile | Distinctly sweet and potent. | Similar taste but with some medicinal characteristics removed. |
Making an Informed Decision for Bedtime
Given the conflicting effects, it is best to approach the consumption of licorice before bed with caution. For most people, a small amount of DGL licorice for digestive relief is unlikely to cause issues. However, consuming products with significant levels of real glycyrrhizin before sleep is generally not recommended due to the risk of raising blood pressure and disturbing sleep. The dose-response relationship is clear: higher consumption over longer periods increases the risk of side effects.
It is always wise to consult a healthcare provider before incorporating any new herbal remedy into your routine, particularly if you have pre-existing conditions like hypertension, heart disease, or kidney problems. Your doctor can help you assess the potential risks and benefits based on your individual health profile. For those seeking calming, sleep-promoting teas, reliable alternatives like chamomile or peppermint are often better choices.
Conclusion: Making an Informed Decision Ultimately, whether it is okay to eat licorice before bed depends on the form and amount. While DGL licorice presents a safer option for general health, real licorice containing glycyrrhizin carries a significant risk of increasing blood pressure and causing fluid retention, which can severely impact sleep. Given these potential side effects, most health professionals recommend caution. For those seeking a natural sleep aid, other herbs are a more reliable and safer choice. For more information on licorice safety and interactions, consult the WebMD resource on Licorice.
