Licorice root, harvested from the roots and underground stems of the Glycyrrhiza glabra plant, has been used worldwide for thousands of years as an herbal medicine and added sweet flavor to food and beverages.
In traditional Ayurveda, as well as in Chinese medicine, the whole root was used for thousands of years without side effects. They typically used the whole root in small, safe dosages as part of larger herbal formulations. In Ayurveda, licorice is used as a natural lubricant or demulcent for the intestinal tract and respiratory airways.
One of the active constituents of licorice is glycyrrhizin. For years, herbal extracts were used to concentrate the glycyrrhizin in an attempt to make the licorice effects more potent. In foods, glycyrrhizin became popular because it is 50 times as sweet as sucrose, and because it is an herbal sweetener.
Things changed when research was published that linked the over-consumption of licorice root to a rise in blood pressure. (2) At high dosages, glycyrrhizin can have an aldosterone-like effect where it elevates sodium and potassium levels, in turn, raising blood pressure. (2)
Most of these blood pressure issues would arise when the licorice root was over-consumed as an extract, or concentrated to be used as a natural sweetener, as found in many soft drinks and snack foods.
In its raw, whole root form, licorice is quite safe. One would have to ingest massive quantities to experience any problems.
In This Article
Deglycyrrhizinated Licorice or DGL
To address the side effect of over-using licorice extracts as an herbal supplement and in the food industry as a natural sweetener, a chemical process was developed to remove the glycyrrhizin compound from the root, and they called it deglycyrrhizinated licorice or DGL.
Today, in western herbal medicine, DGL has become the standard for supplements containing licorice. If a product has had the glycyrrhizin removed, the label will usually specify “DGL Licorice.”
By doing so, the licorice root is permanently altered. While it may be safer at high dosages for folks with high blood pressure, it’s natural synergistic properties that were counted on in Ayurveda and Chinese medicine for thousands of years has been lost.
Once again, we see humans trying to “improve” upon nature and it almost always seems to backfire. So, before you write whole licorice root off your herbal or food list, let’s take a look at the research—it might surprise you!
How Much Is Dangerous?
According to the science, the amount of licorice that it would take to raise blood pressure levels would be more than 120 standard size veggies caps (500 milligrams each) of the raw licorice root powder. That is basically an entire bottle of encapsulated whole licorice powder. (1,2)
These numbers were confirmed in 1991 when the European Union proposed a provisional figure of 100 milligrams per day as the upper limit for ingestion of glycyrrhizin. This is approximately the amount found in 60–70 grams of licorice. (1,2)
Once again, the problems arise when we start extracting and concentrating herbs. When herbs are concentrated or extracted, the original properties are changed:
- They are soaked in alcohol, which kills the beneficial microbes that are carried from the soil to our digestive tract. (3)
- The number of side effects from herbs are almost always linked to herbal extracts–not the whole herb. (4)
- The body is more likely to build a tolerance or become dependent on concentrated extracts rather than whole herbs. (3,4)
Note: Full spectrum extracts are now becoming the norm (although not required in the US) where the extract botanical chemical profile must match the whole plant prior to the extraction. These full spectrum extracts may not have the microbial intelligence of the original plant, but it does guarantee a consistent delivery of active constituents which are thought to be responsible for the therapeutic value of that herb. In this regard, I use extracts to boost a therapeutic effect for short durations, then wean and reset with a whole, raw herb in its most natural state—microbes attached.
For more information on the difference between whole herbs and extracts, please read the following articles:
- Turmeric Health Benefits Outperform Curcumin (Turmeric Extract)
- 1000 Reasons to Avoid Herbal Extracts
- Extracts: Avoid Dangerous Herbs
The Risk of Licorice Extracts
Here is the reason for concern with licorice extracts: Licorice fluid extracts contain approximately 10-20% glycyrrhizin; typical doses of 2-4ml deliver 200-800 milligrams. A review concluded that about 2% of regular consumers have a daily intake of glycyrrhizinic acid of over 100 milligrams/day. (2,5)
In a 1994 study, a daily oral intake of 1-10mg of glycyrrhizin, which corresponds to 1-5 grams of licorice, was estimated to be a safe dose for healthy adults. (2,6) That would be from 1000 milligrams up to 5000 milligrams a day of raw licorice powder.
Then, also in 1994, over a course of 4 weeks, researchers gave daily doses of 108, 217, 380 and 814mg of glycyrrhizic acid as “licorice pills” for to four groups of 3 male and 3 female healthy volunteers. Based on the study results, the no-observed-adverse-effect level (NOAEL) was 217 mg/person/day. (2,7) That is an unobtainable amount of raw licorice powder, adding up to be more than 250 standard-size 500 milligram capsules per day.
At higher doses, sodium retention and depression of plasma renin and aldosterone levels were observed. Female participants were slightly more sensitive to glycyrrhizinic acid than male participants.
Hopefully, you can see that the real concern here is with the extracts or concentrated forms of licorice. The traditional use of whole, raw licorice root is actually very safe. (2,7)
The Amount of Licorice in LifeSpa’s Slippery Elm Prebiotic Formula
I wrote this article because I receive many questions regarding the safety of our Slippery Elm Prebiotic Formula, which I encourage to my patients to support the intestinal lining and create a platform of substrate for the re-population of a healthy and permanent stable of beneficial intestinal bacteria.
The formula consists of equal parts of chopped licorice root, marshmallow root and slippery elm bark. You take 1 tablespoon of each of those, soak them in 2 quarts of water and cook them down to a half quart of liquid. That 1 tablespoon of raw licorice root is taken in small dosages over 3 days. That is 1 tablespoon of chopped licorice root taken over 3 days. This is a tiny amount of licorice!
There are 56 grams of licorice root in a month’s supply of the Slippery Elm Prebiotic Formula – which comes out to be 1.8 grams of raw licorice per day. Most studies suggest more than 60 grams of the raw licorice would need to be ingested daily to actually cause a problem.
The most conservative study recommended the safe dose of 1 to 5 grams of raw licorice root powder per day. At 1.8 grams a day, the dosage in the LifeSpa Slippery Elm Prebiotic Formula is well within the safe range.
- Maas P. (2000) Zoethout in levensmiddelen: onderzoek naar het glycyrrhizine gehalte van thee, kruidenmengsels, dranken en drop [Liquorice root in food stuffs: survey of the glycyrrhizin content of tea, herbal mixtures, alcoholic drinks and liquorice] (in Dutch). De Ware(n) Chemicus30: 65–74