In one study looking at the effect of garlic on blood glucose, researchers found that combining garlic extract with metformin was more effective than taking metformin by itself in reducing fasting glucose [5]. This information relates to an herbal, vitamin, mineral or other dietary supplement. Supplementation of garlic does not appear to significantly reduce fasting blood glucose in persons with metabolic syndrome. No significant influence of garlic supplement on creatinine concentrations in serum are present. The rate (frequency of occurring) of the common cold has twice been found to be reduced by 60-70% in persons who take garlic supplementation daily; this is associated with both allicin and the aged garlic extract, and requires higher doses (2.5g aged extract or 180mg allicin). 800mg aged garlic extract has failed to reduce the risk of developing gastric cancer when taken daily for 7.3 years. Each standard 180 mg of Allimax is equivalent of 20 cloves of garlic, so you would only need to take one per day. There is little information regarding the toxicology of garlic. Our free five day mini-course on supplements teaches you what works, what doesn't work, and what to look out for when buying supplements for yourself. While heterogeneity of studies was low, the definition of "high intake" varied greatly among studies, ranging from every meal or every day to a few times a month.105 A Chinese case-control study found that consumption of raw garlic reduced the risk for lung cancer.95, A relationship between an increase in allium food consumption (onion and garlic) may exist with a decreased incidence of benign prostatic hyperplasia.62, A Cochrane systematic review of data found only one 12-week study (n = 146) that showed significantly fewer cold episodes and days of illness with garlic compared with placebo but similar recovery times between the 2 groups. How much garlic is needed to boost your immune system. No hard outcomes data from the study period were reported.96, In South Korean patients with mild hepatic dysfunction and an elevated gamma-glutamyl transpeptidase (GGT), administration of fermented garlic extract (1.5 g/day) for 12 weeks provided a significant decrease in GGT compared to controls but only in the subgroup of patients who consumed alcohol in the 6 weeks prior to the study (P=0.015). 9 November 2020, There is an increase in NK cell activity alongside the increase in NK cell content, although it is not sure if there is an inherent increase in NK cell activity if you control for the increase in cell content. Karin Ried, Oliver R Frank, Nigel P Stocks, Peter Fakler, and Thomas Sullivan Effect of garlic on blood pressure: A systematic review and meta-analysis BMC Cardiovasc Disord. Garlic is considered relatively nontoxic and the availability of human data makes studies in animals with dyslipidemia irrelevant. Garlic also uses the hydrogen sulfide signaling system to exert its anti-cancer effects. Achieving Optimal Health and Longevity on a Low Calorie, Vegan Diet. Required fields are marked *. No significant changes were seen in serum triglyceride or high-density lipoprotein levels.91 As an adjunct to conventional medical treatment, the effect of garlic powder supplementation on plasma lipids, lipoproteins, and carotid intima-media thickness (CIMT) was measured to determine cardiovascular risk and progression of atherosclerosis in patients with coronary artery disease. Similar to symptoms of sickness in general and the length of sickness, the therapeutic efficacy of garlic appears to be modest at best. Quality of life in cancer patients is unaffected despite an increase in NK cell activity, thought to be indicative of a therapeutic effect of supplementation. Enter your email to get our free mini-course on supplementation. Meaning, they didn’t actually have allicin in the capsule in a stable form but relied on a reaction to take place in the stomach. It’s a bit of a mixed bag: some studies show that garlic is effective whereas others show it’s not. Your email address will not be published. Males who were given raw garlic saw their total cholesterol drop from 269 mg/dl to 233 mg/dl, while females saw their cholesterol drop from 260 mg/dl to 233 mg/dl after treatment. Mineral bioaccumulation from garlic ingestion (allicin in particular) is reduced in persons working in a car battery factory with excessive lead levels to a level similar to the reference drug D-penicillamine, The lone study assessing nitric oxide and garlic noted that a raw garlic clove (2g) could increase nitric oxide by 224% in otherwise healthy persons within 2-4 hours of ingestion; potency did not decrease after seven days, The lone pilot study has noted a 32% reduction in prostatic size after a month of eating 200mg/kg garlic (as a water soluble liquid extract), The lone study (no placebo control) noted a 60% reduction in both total and free PSA in a small group of men with prostate cancer; requires more evidence to evaluate the therapeutic potential. They determined that for the studies in which garlic had a positive effect and reducing both systolic and diastolic blood pressure, the garlic powder dosages ranged between 600 – 900 mg per day, which provided approximately 3.6 – 5.4 mg of allicin [1]. Stasis has been reported in the growth of arterial plaque over 48 months when people consume 900mg of garlic, but this effect may only be statistically significant for women. Despite the potent efficacy in reducing the occurrence of sickness, the actual severity of symptoms is only modestly reduced with garlic. 2013;6:49-56. You will be notified when any significant update is made. The investigators cited poor compliance in the 4-capsule group as a potential explanation for superior result with 2 capsules.93 Garlic cannot be recommended for the management of hypertension at this stage.38, 39, 40, 41 A meta-analysis, however, investigated the effects of garlic on blood pressure from data of 18 randomized controlled trials published between January 1946 and November 2013 and found a statistically significant improvement in systolic and DBP of 3.75 mm Hg and 3.39 mm Hg (P < 0.001 each) compared to controls, with subgroup analysis favoring benefit in hypertensive patients. Information tailored to you, updated every month. We have a strict editorial process. HbA1c (%) also dropped from 7.40 to 7.05 for the garlic + metformin group vs 7.67 to 7.45 for the metformin-only group. It’s been found that taking garlic every day can have comparable effects to prescribed blood pressure medications such as beta blockers, ACE inhibitors, and angiotensin II type 1 receptor antagonists. I'm Matt, 35 years old, and I've been blogging since 2006 to help educate people about nutrition, health, and longevity. More side effects, mostly GI symptoms such as gastric pain and nausea, were reported in the garlic group (P < 0.01).102, Garlic juice and essential garlic oil, water, and ethanol extracts exhibit inhibitory effects in vitro on gram-positive and gram-negative bacteria, as well as fungal pathogens.2, 5, Garlic inhibited Helicobacter pylori in in vitro studies and in rodents.6, 7 Garlic has been shown to inhibit Pseudomonas aeruginosa in vitro and in animal models.8, In the an intervention trial conducted in Shandong Province, China, inhibition of H. pylori was described.6, 9 A Cochrane review found few quality trials to evaluate for garlic in the prevention of the common cold. 6. Statistically significant reductions from baseline were observed in SBP (mean difference −5 mm Hg; P = 0.016) but not DBP. No significant alterations in homocysteine concentrations are seen with garlic supplementation. There are countless uses for garlic and many studies have been conducted on the health benefits for the prevention and treatment of a variety of health conditions. for this page. The long study to assesss basal viscosity of the blood has failed to find an interaction with garlic supplementation. The lipid indices that showed significant improvement with garlic supplementation were HDL cholesterol (P = 0.003) and plasma triacylglycerols (P = 0.021). Mild GI adverse reactions (eg, bloating, flatulence, nausea) have been commonly reported with use. The dose of garlic used: 3 grams of raw garlic for 90 days (7.5 to 13.5 mg of allicin). You are now following Garlic. C-reactive protein levels compared with baseline were reduced in the treatment group, and higher than baseline in the placebo group. They saw that two types of immune cells, Natural killer cells, and innate lymphocytes, proliferated better and were more activated than the placebo group cells [6]. Bleeding may occur. The length that one is sick for is only modestly reduced with garlic supplementation even at higher doses. Data sources include IBM Watson Micromedex (updated 2 Nov 2020), Cerner Multum™ (updated 2 Nov 2020), ASHP (updated 23 Oct 2020) and others. The minimum effective dose for raw garlic is a single segment of a garlic bulb (called a clove), eaten with meals two or three times a day. is intended to be used for educational and information purposes only. The platelets from healthy subjects who had eaten garlic cloves (100 to 150 mg/kg) showed complete inhibition to aggregation induced by 5-hydroxytryptamine.15 Other studies have shown that ingestion of aged garlic extract can produce an inhibition of some of the platelet functions important for initiating thromboembolic events in arterial circulation.16 However, the ingestion of 4.2 g of raw garlic over 1 week did not impair platelet function in a small study of 18 patients,17 and in a double-blind, placebo-controlled study of 14 men, garlic did not affect platelet aggregation.18 In this regard, case studies of a direct causal relationship between garlic consumption and warfarin-related bleeding are lacking. Bleeding may occur. American Indians used garlic as a remedy for earaches, flatulence, and scurvy. Heterogeneity exists among trials, as well as poor methodology and a lack of standardization of preparations. The team includes nutrition researchers, registered The dose of garlic used: 250 mg BD (twice a day). Aged garlic extract was well tolerated.113, The clinical practice guideline from the American College of Physicians/American College of Cardiology Foundation/American Heart Association/American Association for Thoracic Surgery/Preventive Cardiovascular Nurses Association/Society of Thoracic Surgeons regarding management of stable ischemic heart disease (2012) recommend that treatment with garlic, coenzyme Q10 (CoQ10), selenium, or chromium should not be used with the intent of reducing cardiovascular risk or improving outcomes in patients with stable ischemic heart disease (strong recommendation; low-quality evidence).90, A randomized, placebo-controlled trial (n = 65) of aged garlic extract plus CoQ10 showed significant improvements in vascular elasticity (pulse-wave velocity) and endothelial function (digital thermal monitor area under the temperature curve) compared with placebo after treatment for 1 year. The potency is less than. Garlic does not appear to lower blood glucose, cholesterol, or blood pressure by a clinically significant degree. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to this product. 3. However, one meta-analysis published in 2013 looked at patients with high cholesterol (hypercholesterolemia) by reviewing 39 primary trials and found that garlic was effective at reducing total cholesterol and LDL cholesterol in individuals with total cholesterol over 200 mg/dl [3]. In order to post comments, please make sure JavaScript and Cookies are enabled, and reload the page. Consider therapy modification.71, 72, 73, 74, Anticoagulants: Herbs (anticoagulant/antiplatelet properties) may enhance the adverse/toxic effect of anticoagulants. As mentioned earlier, garlic extract containing allicin was able to significantly reduce the number of infections with the common cold, indicating that perhaps allicin is the main ingredient in garlic that is responsible for its anti-viral effects.