Nutritional Supplement

Garlic

Also indexed as: Allium sativum

How to Use It

People who wish to consume garlic and have no aversion to its odor can chew from one to two whole cloves of raw garlic daily. For those who prefer it with less odor, enteric-coated tablets or capsules with approximately 1.3% allin are available. Clinical trials have used 600–900 mg (delivering approximately 5,000–6,000 mcg of allicin potential) per day in two or three divided amounts.83,84 Aged-garlic extracts have been studied in amounts ranging from 2.4–7.2 grams per day.

References

1. Koch HP, Lawson LD (eds). Garlic: The Science and Therapeutic Application of Allium sativaum L and Related Species, 2d ed. Baltimore: Williams and Wilkins, 1996, 62-4.

2. Warshafsky S, Kamer R, Sivak S. Effect of garlic on total serum cholesterol: A meta-analysis. Ann Int Med 1993;119(7)599-605.

3. Silagy C, Neil A. Garlic as a lipid-lowering agent—a meta-analysis. J R Coll Phys London 1994;28(1):39-45.

4. Neil HA, Silagy CA, Lancaster T, et al. Garlic powder in the treatment of moderate hyperlipidaemia: A controlled trial and a meta-analysis. J R Coll Phys 1996;30:329-34.

5. McCrindle BW, Helden E, Conner WT. Garlic extract therapy in children with hypercholesterolemia. Arch Pediatr Adolesc Med 1998;152:1089-94.

6. Isaacsohn JL, Moser M, Stein EA, et al. Garlic powder and plasma lipids and lipoproteins. Arch Intern Med 1998;158:1189-94.

7. Berthold HK, Sudhop T, von Bergmann K. Effect of a garlic oil preparation on serum lipoproteins and cholesterol metabolism. JAMA 1998;279:1900-2.

8. Legnani C, Frascaro M, Guazzaloca G, et al. Effects of a dried garlic preparation on fibrinolysis and platelet aggregation in healthy subjects. Arzneim-Forsch Drug Res 1993;43:119-22.

9. Silagy CA, Neil HA. A meta-analysis of the effect of garlic on blood pressure. J Hyperten 1994;12:463-8.

10. Kleijnen J, Knipschild P, Ter Riet G. Garlic, onion and cardiovascular risk factors: A review of the evidence from human experiments with emphasis on commercially available preparations. Br J Clin Pharmacol 1989;28:535-44.

11. Koscielny J, Klüendorf D, Latza R, et al. The antiatherosclerotic effect of Allium sativum. Atherosclerosis 1999;144:237-49.

12. Hughes BG, Lawson LD. Antimicrobial effects of Allium sativum L. (garlic), Allium ampeloprasum L. (elephant garlic) and Allium cepa L. (onion), garlic compounds and commercial garlic supplement products. Phytother Res 1991;5:154-8.

13. Dorant E, van der Brandt PA, et al. Garlic and its significance for the prevention of cancer in humans: A critical view. Br J Cancer 1993;67:424-9 [review].

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15. Koscienlny J, Klüßendorf D, Latza R, et al. The anti-atherosclerotic effect of Allium sativum. Atherosclerosis 1999;144:237-49.

16. Neil HA, Silagy CA, Lancaster T, et al. Garlic powder in the treatment of moderate hyperlipidaemia: A controlled trial and a meta-analysis. J R Coll Phys 1996;30:329-34.

17. McCrindle BW, Helden E, Conner WT. Garlic extract therapy in children with hypercholesterolemia. Arch Pediatr Adolesc Med 1998;152:1089-94.

18. Isaacsohn JL, Moser M, Stein EA, et al. Garlic powder and plasma lipids and lipoproteins. Arch Intern Med 1998;158:1189-94.

19. Berthold HK, Sudhop T, von Bergmann K. Effect of a garlic oil preparation on serum lipoproteins and cholesterol metabolism. JAMA 1998;279:1900-2.

20. Lawson L. Garlic oil for hypercholesterolemia—negative results. Quart Rev Natural Med Fall 1998;185-6.

21. Lawson LD. Garlic powder for hyperlipidemia—analysis of recent negative results. Quart Rev Natural Med Fall, 1998;187-9.

22. Kiesewetter H, Jung F, Pindur G, et al. Effect of garlic on thrombocyte aggregation, microcirculation and other risk factors. Int J Pharm Ther Toxicol 1991;29(4):151-5.

23. Srivastava KC, Tyagi OD. Effect of a garlic derived principle (ajoene) on aggregation and arachidonic acid metabolism in human blood platelets. Prostagl Leukotr Ess Fatty Acids 1993;49:587-95.

24. Munday JS, James KA, Fray LM, et al. Daily supplementation with aged garlic extract, but not raw garlic, protects low density lipoprotein against in vitro oxidation. Atherosclerosis 1999;143:399-404.

25. Kiesewetter H, Jung F, Mrowietz C, et al. Effects of garlic on blood fluidity and fibrinolytic activity: A randomised, placebo-controlled, double-blind study. Br J Clin Pract Suppl 1990;69:24-9.

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28. Yan LJ, Droy-Lefaix MT, Packer L. Ginkgo biloba extract (EGb 761) protects human low density lipoproteins against oxidative modification mediated by copper. Biochem Biophys Res Comm 1995;212:360-6.

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30. Ried K. Garlic lowers blood pressure in hypertensive subjects, improves arterial stiffness and gut microbiota: A review and meta-analysis. Exp Ther Med 2020;19:1472–8.

31. Schwingshackl L, Missbach B, Hoffmann G. An umbrella review of garlic intake and risk of cardiovascular disease. Phytomedicine. 2016 Oct;23(11):1127–33.

32. Xiong XJ, Wang PQ, Li SJ, et al. Garlic for hypertension: A systematic review and meta-analysis of randomized controlled trials. Phytomedicine. 2015;22:352–61.

33. Ried K, Travica N, Sali A. The effect of aged garlic extract on blood pressure and other cardiovascular risk factors in uncontrolled hypertensives: the AGE at Heart trial. Integr Blood Press Control 2016;9:9–21.

34. Mahdavi-Roshan M, Nasrollahzadeh J, Mohammad Zadeh A, Zahedmehr A. Does Garlic Supplementation Control Blood Pressure in Patients with Severe Coronary Artery Disease? A Clinical Trial Study. Iran Red Crescent Med J 2016;18:e23871.

35. Zhu Y, Anand R, Geng X, et al. A mini review: garlic extract and vascular diseases. Neurol Res 2018;40:421–425.

36. Choudhary PR, Jani RD, Sharma MS. Effect of Raw Crushed Garlic (Allium sativum L.) on Components of Metabolic Syndrome. J Diet Suppl 2018;15:499–506.

37. Bahadoran Z, Mirmiran P, Momenan AA, et al. Allium vegetable intakes and the incidence of cardiovascular disease, hypertension, chronic kidney disease, and type 2 diabetes in adults: a longitudinal follow-up study. J Hypertens 2017;35:1909–16.

38. Wan Q, Li N, Du L, et al. Allium vegetable consumption and health: An umbrella review of meta-analyses of multiple health outcomes. Food Sci Nutr 2019;7:2451–70.

39. Sun YE, Wang W, Qin J. Anti-hyperlipidemia of garlic by reducing the level of total cholesterol and low-density lipoprotein: A meta-analysis. Medicine 2018;97:e0255.

40. Ried K. Garlic lowers blood pressure in hypertensive individuals, regulates serum cholesterol, and stimulates immunity: an updated meta-analysis and review. J Nutr 2016;146:389S–96S.

41. Shabani E, Sayemiri K, Mohammadpour M. The effect of garlic on lipid profile and glucose parameters in diabetic patients: A systematic review and meta-analysis. Prim Care Diabetes 2019;13:28–42.

42. Sobenin IA, Myasoedova VA, Iltchuk MI, et al. Therapeutic effects of garlic in cardiovascular atherosclerotic disease. Chin J Nat Med 2019;17:721–8.

43. Warshafsky S, Kamer R, Sivak S. Effect of garlic on total serum cholesterol: A meta-analysis. Ann Int Med 1993;119(7)599-605.

44. Silagy C, Neil A. Garlic as a lipid-lowering agent—a meta-analysis. J R Coll Phys London 1994;28(1):39-45.

45. Neil HA, Silagy CA, Lancaster T, et al. Garlic powder in the treatment of moderate hyperlipidaemia: A controlled trial and a meta-analysis. J R Coll Phys 1996;30:329-34.

46. McCrindle BW, Helden E, Conner WT. Garlic extract therapy in children with hypercholesterolemia. Arch Pediatr Adolesc Med 1998;152:1089-94.

47. Isaacsohn JL, Moser M, Stein EA, et al. Garlic powder and plasma lipids and lipoproteins. Arch Intern Med 1998;158:1189-94.

48. Berthold HK, Sudhop T, von Bergmann K. Effect of a garlic oil preparation on serum lipoproteins and cholesterol metabolism. JAMA 1998;279:1900-2.

49. Lawson L. Garlic oil for hypercholesterolemia—negative results. Quart Rev Natural Med Fall 1998;185-6.

50. Lawson LD. Garlic powder for hyperlipidemia—analysis of recent negative results. Quart Rev Natural Med Fall, 1998;187-9.

51. Kiesewetter H, Jung F, Jung EM, et al. Effects of garlic coated tablets in peripheral arterial occlusive disease. Clin Investig 1993;71:383-6.

52. Josling P. Preventing the common cold with a garlic supplement: a double-blind, placebo-controlled survey. Adv Ther2001;18:189-93.

53. Nantz MP, Rowe CA, Muller CE, et al. Supplementation with aged garlic extract improves both NK and γδ-T cell function and reduces the severity of cold and flu symptoms: a randomized, double-blind, placebo-controlled nutrition intervention. Clin Nutr 2012;31:337-44.

54. Nantz MP, Rowe CA, Muller CE, et al. Supplementation with aged garlic extract improves both NK and γδ-T cell function and reduces the severity of cold and flu symptoms: a randomized, double-blind, placebo-controlled nutrition intervention. Clin Nutr 2012;31:337-44.

55. Mirelman D, Monheit D, Varon S. Inhibition of growth of Entamoeba histolytica by allicin, the active principle of garlic extract (Allium sativum). J Infect Dis 1987;156:243-4.

56. Bastidas CJ. Effect of ingested garlic on Necator americanus and Ancylostoma caninum. Am J Trop Med Hyg 1969;13:920-3.

57. Koch HP, Lawson LD, eds. Garlic: The Science and Therapeutic Application of Allium sativum L. and Related Species. Baltimore: Williams & Wilkins, 1996, 173-4.

58. Abdullah TH, Kirkpatrick DV, Carter J. Enhancement of natural killer cell activity in AIDS with garlic. Dtsch Zschr Onkol 1989;21:52-3.

59. Shoji S, Furuishi K, Yanase R, et al. Allyl compounds selectively killed human immunodeficiency virus (type 1)-infected cells. Biochem Biophys Res Commun 1993;194:610-21.

60. Silverberg N. Garlic cloves for verruca vulgaris. Pediatr Dermatol 2002;19:183. [Letter]

61. Dehghani F, Merat A, Panjehshahin MR, Handjani F. Healing effect of garlic extract on warts and corns. Int J Dermatol2005;44:612-5.

62. Ledezma E, DeSousa L, Jorquera A, et al. Efficacy of ajoene, an organosulphur derived from garlic, in the short-term therapy of tinea pedis. Mycoses 1996;39:393-5.

63. Ledezma E, Marcano K, Jorquera A, et al. Efficacy of ajoene in the treatment of tinea pedis: A double-blind and comparative study with terbinafine. J Am Acad Dermatol 2000;43:829-32.

64. Durak I, Yilmaz E, Devrim E, et al. Consumption of aqueous garlic extract leads to significant improvement in patients with benign prostatic hyperplasia and prostate cancer. Nutr Res 2003;23:199-204.

65. Sivam GP, Lampe JW, Ulness B, et al. Helicobacter pylori--in vitro susceptibility to garlic (Allium sativum) extract. Nutr Cancer 1997;27:118-21.

66. Chung JG, Chen GW, Wu LT, et al. Effects of garlic compounds diallyl sulfide and diallyl disulfide on arylamine N-acetyltransferase activity in strains of Helicobacter pylori from peptic ulcer patients. Am J Chin Med 1998;26:353-64.

67. Ernst E. Is garlic an effective treatment for Helicobacter pylori infection? Arch Intern Med 1999;159:2484-5 [letter].

68. Graham DY, Anderson SY, Lang T. Garlic or jalapeno peppers for treatment of Helicobacter pylori infection. Am J Gastroenterol 1999;94:1200-2.

69. Bingel AS, Farnsworth NR. Higher plants as potential sources of galactagogues. Econ Med Plant Res 1994;6:1-54 [review].

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71. Mohr H. [Clinical investigations of means to increase lactation.] Dtsch Med Wschr 1954;79:1513-6 [in German].

72. Weiss RF. Herbal Medicine. Gothenburg, Sweden: Ab Arcanum and Beaconsfield, UK: Beaconsfield Publishers Ltd., 1988, 318.

73. Mennella JA, Beauchamp GK. Maternal diet alters the sensory qualities of human milk and the nursling's behavior. Pediatrics 1991;88:737-44.

74. Mennella JA, Beauchamp GK. The effects of repeated exposure to garlic-flavored milk on the nursling's behavior. Pediatr Res 1993;34:805-8.

75. Moore GS, Atkins RD. The fungicidal and fungistatic effects of an aqueous garlic extract on medically important yeast-like fungi. Mycologia 1977;69:341-8.

76. Sandhu DK, Warraich MK, Singh S. Sensitivity of yeasts isolated from cases of vaginitis to aqueous extracts of garlic. Mykosen 1980;23:691-8.

77. Prasad G, Sharma VD. Efficacy of garlic (Allium sativum) treatment against experimental candidiasis in chicks. Br Vet J 1980;136:448-51.

78. Arora DS, Kaur J. Anti-microbial activity of spices. Int J Antimicrob Agents 1999;12:257-62.

79. Moore GS, Atkins RD. The fungicidal and fungistatic effects of an aqueous garlic extract on medically important yeast-like fungi. Mycologia 1977;69:341-8.

80. Sandhu DK, Warraich MK, Singh S. Sensitivity of yeasts isolated from cases of vaginitis to aqueous extracts of garlic. Mykosen 1980;23:691-8.

81. Prasad G, Sharma VD. Efficacy of garlic (Allium sativum) treatment against experimental candidiasis in chicks. Br Vet J 1980;136:448-51.

82. Arora DS, Kaur J. Anti-microbial activity of spices. Int J Antimicrob Agents 1999;12:257-62.

83. Brown DJ. Herbal Prescriptions for Better Health. Rocklin, CA: Prima Publishing, 1996, 97-109.

84. Blumenthal M, Busse WR, Goldberg A, et al. (eds). The Complete Commission E Monographs: Therapeutic Guide to Herbal Medicines. Boston, MA: Integrative Medicine Communications, 1998, 134.

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The information presented by TraceGains is for informational purposes only. It is based on scientific studies (human, animal, or in vitro), clinical experience, or traditional usage as cited in each article. The results reported may not necessarily occur in all individuals. For many of the conditions discussed, treatment with prescription or over the counter medication is also available. Consult your doctor, practitioner, and/or pharmacist for any health problem and before using any supplements or before making any changes in prescribed medications. Information expires December 2025.