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Journal of Chiropractic Medicine logoLink to Journal of Chiropractic Medicine
. 2005;4(4):182–190. doi: 10.1016/S0899-3467(07)60149-9

A review of studies of garlic (Allium sativum) on serum lipids and blood pressure before and after 1994: does the amount of allicin released from garlic powder tablets play a role?

Marc P McRae a,*
PMCID: PMC2647046  PMID: 19674660

Abstract

Objective

To identify studies measuring garlic powder tablets effects on systolic and diastolic blood pressure and to investigate if studies published prior to January 1994 would perform better than those published later.

Methods

Using MEDLINE (January 1966 through December 2004) studies involving human subjects that examined the effect of garlic (Allium sativum) on serum lipids and blood pressure were obtained. Studies that were conducted using garlic in the form of garlic powder tablets were included in the data extraction. Correlation coefficients were calculated for total serum cholesterol, systolic and diastolic blood pressure with respect to date of publication. Trials published prior to January 1994 were placed into an “earlier” group and compared to the “latter” group of studies published from January 1994 onward.

Results

Eighteen trials were identified whereupon the inverse associations between total serum cholesterol, systolic and diastolic blood pressures with respect to time of publication were correlated (−0.614, −0.627, and −0.587 respectively, p < 0.05). No significant associations were observed between systolic and diastolic blood pressure with respect to total serum cholesterol (0.388 and 0.431 respectively). The following differences between the earlier and later groups were observed for total serum cholesterol (31.4 ± 19.0 vs. 3.5 ± 5.8 mg/dl, p = .004); systolic blood pressure (11.0 ± 9.2 vs. 2.0 ± 4.4 mmHg, p = .133) and diastolic blood pressure (5.8 ± 3.4 vs. 0.9 ± 2.4 mmHg, p = .018).

Conclusions

Publications published prior to January 1994 performed better than those published after January 1994, suggesting that allicin may be responsible for the antihypertensive effects of garlic powder tablets. However, a lack of correlation between changes in total serum cholesterol and blood pressure suggests that other organo-sulfur compounds may also play a role in the antihyper-tensive mechanisms of garlic.

Key Indexing Terms: Garlic, Allicin, Alliin, Al-liinase, Blood Pressure, Hypertension

Footnotes

Sources of support: No funds were received for the preparation of this manuscript.

References

  • 1.The World Health Organization . CVD prevention and control: missed opportunities [website] The Association; Geneva, Switzerland: 2003. [cited 2003 Sept 25]. Available from: http://www.who.int/cardiovascular_diseases/prevention_control/en/ [Google Scholar]
  • 2.American Heart Association . Heart disease and stroke statistics 2003 update. American Heart Association; Dallas, TX: 2002. [Google Scholar]
  • 3.Castelli W, Garrison R, Wilson P, Abbott R, Kalousdian S, Kannel W. Incidence of coronary heart disease and lipoprotein cholesterol levels: The Framingham Study. JAMA. 1986;256:2835–2838. [PubMed] [Google Scholar]
  • 4.Rahman K. Historical perspectives on garlic and cardiovascular disease. J Nutr. 2001;131:977S–979S. doi: 10.1093/jn/131.3.977S. [DOI] [PubMed] [Google Scholar]
  • 5.Banerjee S, Maulik S. Effect of garlic on cardiovascular disorders: a review. Nutr J. 2002;1:4. doi: 10.1186/1475-2891-1-4. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 6.Leoper M, DeBray M. Hypotensive effect of tincture of garlic. Prog Med. 1921;36:391–392. [Google Scholar]
  • 7.Silagy C, Neil A. Garlic as a lipid lowering agent: a meta-analysis. J R Coll Phys Lond. 1994;28:39–45. [PMC free article] [PubMed] [Google Scholar]
  • 8.Silagy C, Neil A. A meta-analysis of the effect of garlic on blood pressure. J Hypertens. 1994;12:463–468. [PubMed] [Google Scholar]
  • 9.Stevinson C, Pittler M, Ernst E. Garlic for treating hypercholesterolemia: a meta-analysis of randomized clinical trials. Ann Intern Med. 2000;133:420–429. doi: 10.7326/0003-4819-133-6-200009190-00009. [DOI] [PubMed] [Google Scholar]
  • 10.Lawson L, Wang J, Papadimitriou D. Allicin release under simulated gastrointestinal conditions from garlic powder tablets employed in clinical trials on serum cholesterol. Planta Med. 2001;67:13–18. doi: 10.1055/s-2001-10624. [DOI] [PubMed] [Google Scholar]
  • 11.Agarwal K. Therapeutic actions of garlic constituents. Med Res Rev. 1996;16:111–124. doi: 10.1002/(SICI)1098-1128(199601)16:1<111::AID-MED4>3.0.CO;2-5. [DOI] [PubMed] [Google Scholar]
  • 12.Gebhardt R, Beck H. Differential inhibitory effects of garlic-derived organosulfur compounds on cholesterol biosynthesis in primary rat hepatocyte cultures. Lipids. 1996;31:1269–1276. doi: 10.1007/BF02587912. [DOI] [PubMed] [Google Scholar]
  • 13.Gebhardt R, Beck H, Wagner K. Inhibition of cholesterol biosynthesis by allicin and ajoene in rat hepatocytes and HepG2 cells. Biochim Biophys Acta. 1994;1213:57–62. doi: 10.1016/0005-2760(94)90222-4. [DOI] [PubMed] [Google Scholar]
  • 14.Das I, Khan N, Sooranna S. Potent activation of nitric oxide synthase by garlic: a basis for its therapeutic applications. Curr Med Res Opin. 1995;13:257–263. doi: 10.1185/03007999509111550. [DOI] [PubMed] [Google Scholar]
  • 15.Pedraza-Chaverri J, Tapia E, Medina-Campos O, Granados M, Franco M. Garlic prevents hypertension induced by chronic inhibition of nitric oxide synthesis. Life Sci. 1998;62:71–77. doi: 10.1016/s0024-3205(97)01155-7. [DOI] [PubMed] [Google Scholar]
  • 16.Sharifi A, Darabi R, Akbarloo N. Investigation of antihypertensive mechanism of garlic in 2K1C hypertensive rat. J Ethnopharm. 2003;86:219–224. doi: 10.1016/s0378-8741(03)00080-1. [DOI] [PubMed] [Google Scholar]
  • 17.Turner B, Molgaard C, Marckmann P. Effect of garlic (Allium sativum) powder tablets on serum lipids, blood pressure and arterial stiffness in normo-lipidaemic volunteers: a randomized, double-blind, placebo-controlled trial. Br J Nut. 2004;92:701–706. doi: 10.1079/bjn20041255. [DOI] [PubMed] [Google Scholar]
  • 18.Ziaei S, Hantoshzadeh S, Rezasoltani P, Lamyian M. The effect of garlic tablet on plasma lipids and platelet aggregation in nulliparous preg-nants at high risk of preeclampsia. Eur J Obst Gynecol Rep Bio. 2001;99:201–206. doi: 10.1016/s0301-2115(01)00384-0. [DOI] [PubMed] [Google Scholar]
  • 19.McCrindle B, Helden E, Conne W. Garlic extract therapy in children with hypercholesterolemia. Arch Pediatr Adolesc Med. 1998;152:1089–1094. doi: 10.1001/archpedi.152.11.1089. [DOI] [PubMed] [Google Scholar]
  • 20.Isaacsohn J, Moser M, Stein E. Garlic powder and plasma lipids and lipoproteins: a multicenter, randomized, placebo-controlled trial. Arch Inter Med. 1998;158:1189–1194. doi: 10.1001/archinte.158.11.1189. [DOI] [PubMed] [Google Scholar]
  • 21.Simons L, Balasubramaniam S, Konigsmark M, Parfitt A, Simons J, Peters W. On the effect of garlic on plasma lipids and lipoproteins in mild hypercholesterolemia. Atherosclerosis. 1995;113:219–225. doi: 10.1016/0021-9150(94)05449-s. [DOI] [PubMed] [Google Scholar]
  • 22.Santos O, Johns R. Effects of garlic powder and garlic oil preparations on blood lipids, blood pressure and well being. Br J Clin Res. 1995;6:91–100. [Google Scholar]
  • 23.Saradeth T, Seidl S, Resch K, Ernst E. Does garlic alter the lipid pattern in normal volunteers? Phytomed. 1994;1:183–185. doi: 10.1016/S0944-7113(11)80062-0. [DOI] [PubMed] [Google Scholar]
  • 24.Kiesewetter H, Jung F, Jung E. Effects of garlic coated tablets in peripheral arterial occlusive disease. Clin Invest. 1993;71:383–386. doi: 10.1007/BF00186628. [DOI] [PubMed] [Google Scholar]
  • 25.Jain A, Vargas R, Gotzkosky S, McMahon G. Can garlic reduce levels of serum lipids? A controlled clinical study. Am J Med. 1993;94:632–635. doi: 10.1016/0002-9343(93)90216-c. [DOI] [PubMed] [Google Scholar]
  • 26.Santos O, Grunwald J. Effect of garlic powder tablets on blood lipids and blood pressure-a six month placebo controlled double blind study. Br J Clin Res. 1993;4:37–44. [Google Scholar]
  • 27.Holzgartner H, Schmidt U, Kuhn U. Comparison of the efficacy and tolerance of a garlic preparation vs. bezafibrate. Arzneim-Frosch. 1992;42:1473–1477. [PubMed] [Google Scholar]
  • 28.Grunwald J, Heede J, Albrecht R. Effects of garlic powder tablets on blood lipids and blood pressure-the Danish multicentre Kwai study. Eur J Clin Res. 1992;3:179–186. [Google Scholar]
  • 29.Kiesewetter H, Jung F, Pinder G, Jung E, Mrowietz C, Wenzel E. Effect of garlic on thrombocyte aggregation, microcirculation and other risk factors. Int J Clin Pharm Ther Tox. 1991;29:151–155. [PubMed] [Google Scholar]
  • 30.Auer W, Eiber A, Hertkorn E. Hypertension and hyperlipidemia: garlic helps in mild cases. Br J Clin Pract (Suppl) 1990;69:3–6. [PubMed] [Google Scholar]
  • 31.Vorberg G, Schneider B. Therapy with garlic: results of a placebocontrolled, double blind study. Br J Clin Pract. 1990;44:7–11. [PubMed] [Google Scholar]
  • 32.Harenberg J, Giese C, Zimmermann R. Effect of dried garlic on blood coagulation, fibrinolysis, platelet aggregation and serum cholesterol levels in patients with hyperlipoproteinemia. Atherosclerosis. 1988;74:247–249. doi: 10.1016/0021-9150(88)90244-4. [DOI] [PubMed] [Google Scholar]
  • 33.Kandziora J. The blood pressure lowering and lipid lowering effect of a garlic preparation in combination with a diuretic. Arzt Forschung. 1988;35(3):3–8. [Google Scholar]
  • 34.Kandziora J. Antihypertensive effectiveness and tolerance of a garlic medication. Arzt Forschung. 1988;35(1):1–8. [Google Scholar]
  • 35.McMahon G, Vargas R. Can garlic lower blood pressure? A pilot study. Pharmacotherapy. 1993;13:406–407. [PubMed] [Google Scholar]
  • 36.Gardner C, Chatterjee L, Carlson J. The effect of a garlic preparation on plasma lipid levels in moderately hypercholesterolemic adults. Atherosclerosis. 2001;154:213–220. doi: 10.1016/s0021-9150(00)00466-4. [DOI] [PubMed] [Google Scholar]
  • 37.Andrianova I, Fomchenkov I, Orekhov A. Hypotensive effect of longacting garlic tablets Allicor (a double blind placebo-controlled trial) Ter Arkh. 2002;74:76–78. [PubMed] [Google Scholar]
  • 38.Lawson L, Hughes B. Characterization of the formation of allicin and other thiosulfinates from garlic. Planta Medica. 1992;58:345–350. doi: 10.1055/s-2006-961482. [DOI] [PubMed] [Google Scholar]
  • 39.Lawson L, Wang J. Low allicin release from garlic supplements: a major problem due to the sensitivities of alliinase activity. J Agric Food Chem. 2001;49:2592–2599. doi: 10.1021/jf001287m. [DOI] [PubMed] [Google Scholar]
  • 40.Yeh Y, Liu L. Cholesterol-lowering effect of garlic extracts and organosulfur compounds: human and animal studies. J Nutr. 2001;131:989S–993S. doi: 10.1093/jn/131.3.989S. [DOI] [PubMed] [Google Scholar]
  • 41.Liu L, Yeh Y. S-Alk(en)yl cysteines of garlic inhibit cholesterol synthesis by deactivating HMG-CoA reductase in cultured rat hepatocytes. J Nutr. 2002;132:1129–1134. doi: 10.1093/jn/132.6.1129. [DOI] [PubMed] [Google Scholar]
  • 42.Yeh Y, Lin R, Yeh S, Evans S. Garlic reduces plasma cholesterol in hypercholesterolemic men maintaining habitual diets. In: Ohigashi H, Osawa T, editors. Food factors for Cancer Prevention. Springer-Verlag; Tokyo, Japan: 1997. pp. 226–230. [Google Scholar]
  • 43.Morihara N, Sumioka I, Moriguchi T, Uda N, Kyo E. Aged garlic extract enhances production of nitric oxide. Life Sci. 2002;71:509–517. doi: 10.1016/s0024-3205(02)01706-x. [DOI] [PubMed] [Google Scholar]
  • 44.Steiner M, Khan H, Holbert D, Lin R. A double-blind crossover study in moderately hypercholesterolemic men that compared the effect of aged garlic extract and placebo administration on blood lipids. Am J Clin Nutr. 1996;64:866–870. doi: 10.1093/ajcn/64.6.866. [DOI] [PubMed] [Google Scholar]
  • 45.Durak I, Kavutcu M, Aytac B. Effects of garlic extract consumption on blood lipid and oxidant/antioxidant parameters in humans with high blood cholesterol. J Nutr Biochem. 2004;15:373–377. doi: 10.1016/j.jnutbio.2004.01.005. [DOI] [PubMed] [Google Scholar]
  • 46.Amagase H, Petesch B, Matsuura H, Kasuga S, Itakura Y. Intake of garlic and its bioactive components. J Nutr. 2001;131:955S–962S. doi: 10.1093/jn/131.3.955S. [DOI] [PubMed] [Google Scholar]
  • 47.Kaye A, DeWitt B, Anwar M. Analysis of responses of garlic derivatives in the pulmonary vascular bed of the rat. J Appl Physiol. 2000;89:353–358. doi: 10.1152/jappl.2000.89.1.353. [DOI] [PubMed] [Google Scholar]
  • 48.Neaton J, Wentworth D. Serum cholesterol, blood pressure, cigarette smoking, and death from coronary heart disease. Overall findings and differences by age for 316,099 white men. Multiple Risk Factor Intervention Trial Research Group. Arch Intern Med. 1992;152:56–64. [PubMed] [Google Scholar]

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