What is Licorice Root?
Whilst licorice is best known to most of us as a controversial candy flavour, licorice root (scientific name Glycyrrhiza glabra), has been used medicinally throughout the world since ancient times. Licorice root was traditionally used to treat a number of ailments, including respiratory and digestive symptoms, and as a general wellbeing tonic. Licorice root contains a large number of different active compounds and a great deal of research is currently being done into the potential ability of these ingredients to cure disease and enhance wellbeing. There are two major groups of active ingredients in licorice root. The first, Glycyrrhizin, Glycyrrhyzic acid, and derivatives, give the root it’s sweetness. The second is a group of many similar chemicals known as Flavonoids. Flavonoids are present in many species of plant. Glabridin and Liquiritigenin are the most important flavinoids in licorice root.
Where does Licorice Root come from?
Glycyrrhiza glabra is a plant native to Europe and parts of Asia. After the root is harvested it is dried and consumed whole, or extracted. Extraction can isolate particular active ingredients. “Deglycyrrhizinated licorice” is a popular extract which contains no Glycyrrhizin compounds. Most licorice consumed as food is produced from licorice extract, so this should be taken into account if monitoring intake.
Benefits of Licorice Root
Licorice root has an enormous number of beneficial uses. As scientific study progresses, more of these are coming to light. Many of these studies concentrate on individual ingredients present in the licorice root, for example Glycyrrhizic acid has shown promise in treating such varied conditions as viral infection, cancer, hormonal imbalance and stomach ulcer; Glabridin is being investigated for cognitive, anti-inflammatory and metabolic benefits whilst Liquirtigenin has shown promise as both a stimulant and a fat burner. In modern herbal medicine, Licorice root is used to treat gut symptoms, autoimmune disorders, heart and lung problems, and cognitive decline.
Benefits of Licorice Root for Bodybuilding
The Flavonoids in licorice root are of greatest interest to bodybuilders. Evidence is mounting that licorice root can assist weight loss. Studies in animals show that Glabridin may speed up fat burning by assisting the enzymes that oxidise fatty acids (Lee 2012) and that a number of other flavonoids could prevent fat absorption in the intestine (Birari et al 2011). Further animal studies have also shown that regular Glabridin supplementation may increase liver and muscle glycogen storage, reduce post lactic acid levels, and delay the onset of fatigue during exercise (Sheng et al 2009).
A heavy schedule with inadequate energy intake can negatively effect mood and alertness, which may make training goals harder to attain. Licorice flavonoids may support and improve cognitive ability, particularly in situations where the body is stressed, such as when the body is operating on an energy deficit (Lin et al 2012). Glabridin and other flavinoids in licorice root were shown to limit serotonin reuptake in the brain by up to 60% (Ofir et al 2003). Serotonin is a mood regulating neurotransmitter, and limiting reuptake has been shown to alleviate depression and anxiety. In addition, many of the flavonoid chemicals present in licorice root have demonstrated antioxidant and anti-inflammatory properties, which may assist with recovery (Lin et al 2012, Lee 2012).
Side Effects, Safety & Negatives of Licorice Root
A number of active components in licorice root are known to generate side effects. Glabridin is a potent inhibitor of an enzyme called CYP3A4, which plays an important role in the metabolism of many common medicines (Tsukamoto 2005). Because this has potential to lead to harmful drug interactions, speaking with a doctor is recommended before commencing regular supplementation with licorice root. A recommended dosage regime of licorice root can reduce levels of testosterone in healthy men and women by as much as 26% through the action of Glycyrrhyzic acid (Armanini 2004a, b). Glycyrrhyzic acid also raises blood cortisol levels through the deactivation of an enzyme. Raised cortisol levels may lead to a condition called Psuedoaldosteronism, which causes high blood presssure, fluid retention and metabolic imbalances (Shibata 2000). These side effects can be avoided through use of a deglycyrrizinated licorice root extract. These are popular and readily available. Although studies have delivered promising results on the benefits of licorice root supplementation, much of the reported research outcomes have not yet been tested in healthy human subjects.
Licorice Root Recommended Doses and Ingredient Timing
Licorice root may be taken at any time, but it is generally accepted that benefits of supplementation take between a week and a month to become apparent, so a sustained regime will bring greatest benefit. The European Commission guidelines suggest consumption of no more than 100mg Glycyrrhizic acid per day to avoid side effects. Natural products are variable in their concentration of active ingredients and the concentration of glycyrrhizic acid in dry licorice root is said to average 1.5% (0.1-4%) (Wang & Yang 2007). This equals just under 7g of dried root. Traditional Chinese Medicine suggests 8-25g of Licorice root daily and up to 100g during periods of disease.
Licorice Root Supplements
Licorice root is often included as an ingredient in multivitamins, and superfood supplements.
Stacking Licorice Root
Licorice root is safe to stack with most other nutritional supplements, provided the recommended dose is not exceeded. Stacking Licorice Root with Lycopene, another antioxidant, produces a synergistic effect (Lee 2012).Armanini D, Bonanni G, Mattarello MJ, Fiore C, Sartorato P, Palermo M. Licorice consumption and serum testosterone in healthy man. Exp Clin Endocrinol Diabetes. 2003;111(6):341-3 (a)
Armanini D, Mattarello MJ, Fiore C, Bonanni G, Scaroni C, Sartorato P, Palermo M.Licorice reduces serum testosterone in healthy women. Steroids. 2004; 69(11-12):763-6 (b)
Birari RB, Gupta S, Mohan CG, Bhutani KK. Antiobesity and lipid lowering effects of Glycyrrhiza chalcones: Experimental and computational studies. Phytomedicine. 2011; 18(8-9):795-801
Lee JW, Choe SS, Jang H, Kim J, Jeong HW, Jo H, Jeong KH, Tadi S, Park MG, Kwak TH, Man Kim J, Hyun DH, Kim JB. AMPK activation with glabridin ameliorates adiposity and lipid dysregulation in obesity. J Lipid Res 2012; 53(7): 1277-86
Lin Z Gu J, Xiu J, Mi T, Dong J, Tiwari JK. Traditional Chinese Medicine for Senile Dementia Evid Based Complement Alternat Med. 2012.
Ofir R, Tamir S, Khatib S, Vaya J. Inhibition of Serotonin reuptake by licorice constituents J Mol Neurosci. 2003; 20(2): 135-40
Shang H, Cao S, Wang J. Zheng H, Putheti R. Glabridin from Chinese herb Licorice inhibits fatigue in mice. Afr J Tradit Complement Altern Med. 2009; 7(1): 17-23
Shibata, S. A drug over the millennia: pharmacognosy, chemistry, and pharmacology of licorice. Yakugaku Zasshi. 2000;120 (10): 849–62.
Tsukamoto S, Aburatani M. Yoshida T, Yamashita Y, El-Beih AA, Ohta T. CYP3A4 inhibitors isolated from Licorice. Biol Pharm Bull. 2005; 28(10): 2000-2
Wang YC, Yang YS. Simultaneous quantification of flavonoids and triterpenoids in licorice using HPLC. J Chromatogr B Analyt Technol Biomed Life Sci. 2007; 850(1-2):392-9.