An interventional study of garlic powder added to ambient water and garlic powder added to boiling water in Arteriosclerosis and Intracranial Arteriosclerosis, sponsored by National Center for Complementary and Integrative Health (NCCIH). Completed at 1 site in United States. Open to participants aged 18 Years to 65 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2010-01-11.
Sponsored by National Center for Complementary and Integrative Health (NCCIH) · Not applicable, Interventional, and Prevention
This study will seek to identify the compound(s) in garlic that is (are) responsible for its ability to prevent the formation of blood clots (prevent platelet aggregation) and to determine the maximally effective dose and duration of the benefits. This study will also determine whether "cooked" garlic (garlic powder added to boiling water, no allicin present) is as effective as "fresh" garlic (garlic powder added to ambient water, high allicin present) and, if more than one compound is involved, and whether their combined effects are more significant than the effects of each compound alone.
Published studies indicate that various types of undefined garlic products display antiplatelet activity. However, the compounds responsible for this antiplatelet effect have not been identified.
Acute studies. In acute (one day) studies, healthy participants will consume several doses of "fresh garlic" (garlic powder added to ambient water; up to the equivalent of 12 grams fresh garlic or 52 mg allicin) as a paste in a tuna sandwich. At 0, 2, 4, and 6 hours after consumption, the ability of platelets to aggregate in platelet-rich plasma (PRP) or in whole blood (WB), in response to a drug (collagen, ADP) that stimulates platelet aggregation, will be measured. After establishing the optimum dose and optimum time of the antiplatelet effect for each person, and if the effects are sufficiently strong, the effects of cooked garlic (garlic powder added to boiling water, no allicin present) and seven extracted fractions (oil, protein, fructans, etc.) will be determined, using the fractions at the same dose as their abundance in the established optimum dose of crushed fresh garlic.
Chronic studies. If only weak platelet effects are found for a high acute dose of "fresh" garlic, chronic studies will be conducted. In chronic studies, participants will consume 8.0 grams of "fresh garlic" (2.7 grams garlic powder added to ambient water, allicin content = 35 mg) as a paste in a tuna sandwich every day for four weeks and 8.0 grams of "boiled garlic" (2.7 grams garlic powder added to boiling water) in a sandwich every day for an additional four weeks, after a 1-week washout. The ability of platelets to aggregate in PRP and whole blood will be determined before and every week after garlic consumption begins and after the 1-week washout.
319 studies on the registry are indexed under Arteriosclerosis; 33 are open to participants now.
This study's enrollment of 9 is below the median of 143 across 184 interventional studies indexed under Arteriosclerosis.
Browse Arteriosclerosis studies →National Center for Complementary and Integrative Health (NCCIH) is the lead sponsor of 223 studies on the registry; 7 are open to participants now.
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Exclusion Criteria:
high allicin
Dietary Supplement: garlic powder added to ambient water
no allicin
Dietary Supplement: garlic powder added to boiling water
consumed 2.7 grams of garlic powder added to ambient water (equivalent to 8 grams fresh or raw garlic) in a sandwich, once a day for four weeks
Also known as: Global Marketing Assoc., Inc.
consumed 2.7 grams of garlic powder added to boiling water (equivalent to 8 grams of cooked garlic) in a sandwich, once a day for four weeks
Also known as: Global Marketing Assoc., Inc.
Percent Platelet Aggregation
percent platelet aggregation in collagen-induced platelet aggregation in platelet rich plasma (PRP)
Time frame: 4 weeks
Electrical Impedance in Ohms
Electrical impedance (ohms) was measured using 0.5 mL of whole blood plus 0.5 mL saline in a Chronolog Whole Blood aggregometer. Ten mL of whole blood were collected and tested every week. There is no mathematical correlation between impedance (ohms) and percent aggregation.
Time frame: 4 weeks
healthy participants were recruited in Utah county, Utah, in early 2006
| Milestone | Garlic Powder: High Allicin | Garlic Powder: No Allicin |
|---|---|---|
| Started | 9 | 6 |
| Completed | 9 | 6 |
| Not completed | 0 | 0 |
| Milestone | Garlic Powder: High Allicin | Garlic Powder: No Allicin |
|---|---|---|
| Started | 9 | 6 |
| Completed | 9 | 6 |
| Not completed | 0 | 0 |
| Milestone | Garlic Powder: High Allicin | Garlic Powder: No Allicin |
|---|---|---|
| Started | 9 | 6 |
| Completed | 9 | 6 |
| Not completed | 0 | 0 |
percent platelet aggregation in collagen-induced platelet aggregation in platelet rich plasma (PRP)
| percent platelet aggregation | Garlic Powder: High Allicin | Garlic Powder: No Allicin |
|---|---|---|
| Percent Platelet Aggregation | 71.4 ± 4.3 | 72.5 ± 5.5 |
Electrical impedance (ohms) was measured using 0.5 mL of whole blood plus 0.5 mL saline in a Chronolog Whole Blood aggregometer. Ten mL of whole blood were collected and tested every week. There is no mathematical correlation between impedance (ohms) and percent aggregation.
| ohms | Garlic Powder: High Allicin | Garlic Powder: No Allicin |
|---|---|---|
| Electrical Impedance in Ohms | 13.8 ± 1.5 | 15.0 ± 1.5 |
Non-serious events are listed at a 1% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| Garlic Powder: High Allicin | — | 0/9 (0%) | 0/9 (0%) |
| Garlic Powder: No Allicin | — | 0/6 (0%) | 0/6 (0%) |
| Age, Categorical(Participants) | Garlic Powder: High Allicin | Garlic Powder: No Allicin | Total |
|---|---|---|---|
| <=18 years | 0 | 0 | 0.0 |
| Between 18 and 65 years | 9 | 6 | 15.0 |
| >=65 years | 0 | 0 | 0.0 |
| Age Continuous(years) | Garlic Powder: High Allicin | Garlic Powder: No Allicin | Total |
|---|---|---|---|
| Mean | 32.2 ± 13.7 | 36.5 ± 15.1 | 32.2 ± 13.7 |
| Sex: Female, Male(Participants) | Garlic Powder: High Allicin | Garlic Powder: No Allicin | Total |
|---|---|---|---|
| Female | 4 | 3 | 7.0 |
| Male | 5 | 3 | 8.0 |
| Region of Enrollment(participants) | Garlic Powder: High Allicin | Garlic Powder: No Allicin | Total |
|---|---|---|---|
| United States | 9 | 6 | 15.0 |
| electrical impedance (ohms) at 0 weeks(ohms) | Garlic Powder: High Allicin | Garlic Powder: No Allicin | Total |
|---|---|---|---|
| Mean | 12.7 ± 1.2 | 15.0 ± 1.6 | 13.9 ± 1.4 |
| percent platelet aggregation at 0 weeks(percent platelet aggregation) | Garlic Powder: High Allicin | Garlic Powder: No Allicin | Total |
|---|---|---|---|
| Mean | 76.0 ± 1.6 | 71.8 ± 5.7 | 73.9 ± 3.7 |
The record gives a start of Mar 2006, a primary completion of Sep 2007 and a completion of Sep 2007. It does not say whether these dates are actual or estimated.
Results were first posted in Jan 2010, 2 years 4 months after primary completion.
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This study is completed, as verified in Dec 2009. You cannot join it, but the record below documents what was studied.
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