Cynara scolymus is used for hyperlipidemia, dyspepsia, nausea, alcohol-induced hangover, liver dysfunction, irritable bowel syndrome, and gallstone prevention. It is also used orally as a diuretic and choleretic to promote bile production. Because bile plays an important role in lipid and cholesterol processing, choleretic agents are often used in formulas for elevated lipids and poor fat digestion.
Mechanism of Action
Cynara extracts have a choleretic action, promoting bile production in the liver.1 This action increases the presence of bile acid in the colon and content in the feces and supports beneficial intestinal flora. Animal studies suggest that the hypolipidemic effects of leaf extracts may occur via increased fecal bile acids that support the excretion of cholesterol.2
Cynara also contains a relatively high content of inulin (10%–30% based on dry weight), a fructoligosaccharide (FOS) with recognized prebiotic properties,3 known to have beneficial effects on various metabolic functions and to promote beneficial intestinal bacteria and the absorption of minerals.4 There is growing interest in the use of FOS as medicinal foods to help treat diabetes and other metabolic disorders, as inulin may help control metabolic disorders and its complications via improving glycemic and lipid parameters while modulating levels of insulin and glucagon, thereby regulating carbohydrate and lipid metabolism by lowering blood glucose levels.5
Colonic fermentation of dietary fiber yields short-chain fatty acids (SCFAs) such as acetate, propionate, and butyrate in a healthy intestinal ecosystem. The presence of SCFAs may improve systemic lipids in metabolic disorders by reducing serum free fatty acids. Although inulin is often commercially sourced from chicory and other Aster plants, inulin in Cynara extracts or purified supplements has been shown to support colonic fermentation of SCFAs in human subjects.6
Cynara scolymus is credited with antioxidant effects via its numerous molecular polyphenolic constituents such as hydroxycinnamic acids (e.g., chlorogenic, cynarin, dicaffeoylquinic acids, caffeic and ferulic acids) and flavonoids (luteolin and apigenin glycosides).7,8
Cynara extracts may also protect against endothelial dysfunction (one of the first stages of atherosclerotic diseases), and they have positive effects on cellular adhesion molecules, a type of endogenous lectin that helps adhere and maintain vascular endothelial cells.9
Modern research shows Cynara leaf extracts have antioxidative, hepatoprotective, choleretic, anticholestatic, and antidyspeptic actions that include antiemetic, spasmolytic, and carminative effects.10 A Cochrane review of C. scolymus leaf studies reported that although few rigorous clinical trials exist assessing Cynara leaves for cholesterol, overall beneficial effects are reported and side effects are minimal and transient.11
A randomized controlled trial (RCT) evaluated the effects of C. scolymus leaf extract versus placebo in overweight, hyperlipidemic subjects. Its use was associated with a significant increase in high-density lipoprotein and a decrease in cholesterol and low-density lipoprotein.12 Another human double-blind, placebo-controlled trial noted Cynara leaf extract reduced serum cholesterol in 3-months' time,13 and another study on athletes showed artichoke leaves reduced total cholesterol and improved antioxidant capacity in humans.14
Experimental studies have shown FOS act as bifidogenic agents; stimulate the immune system of the body; decrease pathogenic bacteria in the intestine; relieve constipation; decrease the risk of osteoporosis by increasing mineral absorption, especially of calcium; and reduce the risk of atherosclerosis by lowering the synthesis of triglycerides and fatty acids in the liver and decreasing their level in serum.15
An RCT dosed obese women with either inulin/FOS or placebo and reported that treatment with prebiotics led to an increase in Bifidobacterium and Faecalibacterium prausnitzii and a decrease in pathogenic Bacteroides intestinalis, Bacteroides vulgatus, and Propionibacterium in the feces. This trial findings suggested that selective changes in the gut microbiota of obese women led to modest changes in host metabolism, as suggested by the correlation between some bacterial species and metabolic endotoxemia or metabolomic signatures.16
Safety in Pregnancy and Breastfeeding
The use of Cynara leaf during pregnancy and lactation is without concern, as the plant is considered a nourishing food and works via nutritional and bowel-supportive mechanisms.
One clinical trial evaluated the effects of Cynara leaf extracts by using a concentrated preparation and a relatively high dose and reported that there were no side effects during the study and that the medication was well tolerated.17
Investigational studies have used as little as 500 mg/day; however, this herb is generally considered safe at higher doses, such as 35:1 concentrates dosed at 1,800 mg/day.
The therapeutic properties of C. scolymus leaf preparations have been known since ancient times and have been a traditional liver remedy and weight loss aid for centuries. The traditional use of Cynara leaf extract in gastroenterology is mainly based upon its strong antidyspeptic actions that are mediated by its choleretic (increased bile production) activity. Because bile plays an important role in lipid and cholesterol processing, choleretic agents are often seen in traditional formulas for elevated lipids and poor fat digestion.
1Phytomedicine. 2002;9(8):687–93. Choleretic activity and biliary elimination of lipids and bile acids induced by an artichoke leaf extract in rats. Saénz Rodriguez T, García Giménez D, de la Puerta Vázquez R.
2 Phytother Res. 2012;26(7):1048–52. Artichoke extract lowered plasma cholesterol and increased fecal bile acids in golden Syrian hamsters. Qiang Z, Lee SO, Ye Z, et al.
3 Food Chem. 2016;196:1156–62. Extraction of bioactive carbohydrates from artichoke (Cynara scolymus L.) external bracts using microwave assisted extraction and pressurized liquid extraction. Ruiz-Aceituno L, García-Sarrió MJ, Alonso-Rodriguez B, Ramos L, et al.
4 Ann Acad Med Stetin. 2012;58(1):62–5; discussion 65. Inulin: A valuable nutritional component. Nowak A, Klimowicz A, Bielecka-Grzela S, et al.
5 J Anim Physiol Anim Nutr (Berl). 2017;101 Suppl 1:69–78. Glycaemic and insulinaemic responses of adult healthy warm-blooded mares following feeding with Jerusalem artichoke meal. Glatter M, Bochnia M, Goetz F, et al.
6 Eur J Clin Nutr. 2011;65(12):1279–86. Inulin increases short-term markers for colonic fermentation similarly in healthy and hyperinsulinaemic humans. Fernandes J, Vogt J, Wolever TM.
7 Br J Nutr. 2007;97(5):963–9. Absorption and metabolism of bioactive molecules after oral consumption of cooked edible heads of Cynara scolymus L. (cultivar Violetto di Provenza) in human subjects: A pilot study. Azzini E, Bugianesi R, Romano F, et al.
8 J Food Sci. 2012;77(2):C244–52. Polyphenol compounds in artichoke plant tissues and varieties. Negro D, Montesano V, Grieco S, et al.
9 Life Sci. 2004;76(7):775–82. Artichoke juice improves endothelial function in hyperlipemia. Lupattelli G, Marchesi S, Lombardini R, et al.
10 Phytomedicine. 1997;4(4):369–78. Artichoke leaf extract – Recent findings reflecting effects on lipid metabolism, liver and gastrointestinal tracts. Kraft K.
11 Cochrane Database Syst Rev. 2002;(3):CD003335. Artichoke leaf extract for treating hypercholesterolaemia. Pittler MH, Thompson CO, Ernst E.
12 Int J Food Sci Nutr. 2013;64(1):7–15. Beneficial effects of artichoke leaf extract supplementation on increasing HDL-cholesterol in subjects with primary mild hypercholesterolaemia: A double-blind, randomized, placebo-controlled trial. Rondanelli M, Giacosa A, Opizzi A, et al.
13 Phytomedicine. 2008;15(9):668–75. Artichoke leaf extract (Cynara scolymus) reduces plasma cholesterol in otherwise healthy hypercholesterolemic adults: A randomized, double blind placebo controlled trial. Bundy R, Walker AF, Middleton RW, et al.
14 Int J Sport Nutr Exerc Metab. 2008;18(3):313–27. The influence of supplementation with artichoke (Cynara scolymus L.) extract on selected redox parameters in rowers. Skarpanska-Stejnborn A, Pilaczynska-Szczesniak L, Basta P, et al.
15 J Biosci. 2002;27(7):703–14. Applications of inulin and oligofructose in health and nutrition. Kaur N, Gupta AK.
16 Gut. 2013;62(8):1112–21. Insight into the prebiotic concept: lessons from an exploratory, double blind intervention study with inulin-type fructans in obese women. Dewulf EM, Cani PD, Claus SP, et al.
17 Arzneimittelforschung. 2000;50(3):260–5. Efficacy of artichoke dry extract in patients with hyperlipoproteinemia. Englisch W, Beckers C, Unkauf M, et al.