The Insider’s Guide To Garlic Oil: Benefits & Uses

garlic oil

Garlic Oil Introduction

Known for its pungent flavor, seldom will you see a dish that doesn’t have garlic in it. In some parts of the world, whole cloves of garlic are taken like candies to help lower cholesterol and blood pressure. In other cultures, raw garlic cloves are rubbed on certain fungal skin infections like tinea to help kill the microorganism. Garlic has been used for more than 7,000 years, mostly for food flavoring and condiments. However, many cultures and civilizations depended on the garlic to provide them with the health benefits that modern science is slowly trying to demystify.

Oil Source

Garlic essential oil is extracted from the garlic clove itself. In many cultures, garlic is prepared whole for medicinal purposes while others dry them and have them pulverized into powdery form. Some immerse whole heads of garlic in oil to draw out its essences. This spice is native to the regions of Central Asia although it has been cultivated in almost every other part of the world. Allium sativum, as garlic is known in the scientific community, is believed to have been used by the ancient Greeks and Romans as well as those in Africa rimming the Mediterranean. Today, China produces more than 20 million metric tons of garlic followed by India at 1 million.

Health Properties

The health properties of Allium sativum or garlic is inherently connected to its phytochemicals particularly its sulfuric compounds. These substances provide garlic with the following health properties.

Antiatherosclerotic – helps in the prevention of fatty plaque deposition in the inner walls of the arteries to help prevent atherosclerosis
Anticancer – may help in the prevention of certain cancers through a disruption in the proliferative phase of oncogenesis
Antifungal – helps in the killing or inhibition of the growth and activity of Candida albicans as well as other susceptible fungal species
Antihypercholesterolemic – helps in the reduction of total cholesterol levels in the blood
Antihyperglycemic – helps in the more effective control of blood glucose levels
Antihyperlipidemic – decreases circulating levels of low density lipoproteins while modestly increasing the levels of serum high density lipoproteins
Antihypertensive – facilitates the reduction of arterial blood pressure through nitric oxide stimulation
Anti-inflammatory – helps in the reduction of swelling, pain, and warmth in many inflammatory processes
Antimicrobial – fights and kills a wide variety of microorganisms including bacteria, fungi, parasites, and certain viruses
Antioxidant – helps mitigate the damaging effects of oxidative stress
Antiparasitic – helps in the management of certain parasitic infections such as Giardia lamblia and Entamoeba histolytica infections
Antiseptic – helps kill the microorganisms in a particular body surface
Antiviral – may aid in the control of the viral replication process of susceptible viruses

Health Benefits

The allicin and phytochemical contents of garlic provide a lot of health benefits that are centered on cardiovascular health.

Improves cardiac health – While studies show that blood pressure decreases are quite modest with garlic, it nevertheless provides a safer and more cost-effective alternative to individuals who may be hypertensive and are anxious about the rising costs of antihypertensive medications. Garlic can significantly lower blood pressure to reduce the work of the heart and help improve overall cardiac health. When combined with the overall lipid-lowering profile of garlic, this translates to an even better cardiac health.

Lowers blood lipids – Studies have shown that garlic can reduce serum total cholesterol and low density lipoproteins with a commensurate increase, albeit modestly, in high density lipoproteins. This can help reduce the risk of atherosclerotic events leading to generally healthier coronary functioning. This also helps prevent myocardial infarction and the danger of heart failure.

Boosts the immune system – The antimicrobial effects of garlic is superb in that it is effective against bacteria, viruses, fungi, and even protozoa. This can be a very excellent alternative to expensive antibiotic and antimicrobial treatments. It is particularly effective in reducing the number of sick days for individuals with colds from 5 days to a mere 1.5 days.

Helps better control of diabetes – The overall effect of garlic on a variety of liver enzymes has been shown to provide excellent glycemic control. For individuals with mild to moderate hyperglcycemia, taking garlic oil supplements can help provide for a better control of blood sugar levels.

Helps prevent neurodegenerative disorders – The antioxidant property of garlic can help prevent the development of neurodegenerative disorders such as Alzheimer’s disease and Parkinson’s disease.


In 1999, Ankri and Mirelman conducted a study on the antimicrobial properties of one of garlic’s main ingredients, allicin. The study revealed that it has a wide range of antimicrobial activity against both Gram negative and Gram positive bacteria. These included multidrug-resistant strains of the enterotoxicogenic Escherichia coli. Allicin was also proven to be highly effective against Candida albicans as well as protozoal species of Giardia lamblia and Entamoeba histolytica. Garlic was also shown to have antiviral properties. This was supported by the 2016 study of Taheri et al showing that garlic essential oil can significantly inhibit the production of shiga toxin 2 by the O157:H7 strain of Escherichia coli. The toxin is what produces hemorrhagic colitis as well as a haemolytic-uremic syndrome seen in severe E coli infections. Garlic was shown to suppress the production of shiga toxin while at the same time inhibiting the growth of E coli.

Animal studies show that s-allyl cysteine sulphoxide can significantly decrease blood levels of glucose and lipids while suppressing the activities of a variety of enzymes like acid phosphatase, liver glucose-6-phosphatase, alkaline phosphatase, and lactate dehydrogenase. S-allyl cysteine sulphoxide was also shown to increase the activity of HMG CoA reductase in both the liver and the intestines as well as the hexokinase activity of the liver. Studies reveal that these physiologic and chemical processes can all lead to a significant reduction in diabetic activities. S-allyl cysteine sulphoxide is the precursor of garlic’s principal active ingredient, allicin, and is also found abundantly in garlic oil. A 2013 study by Kumar et al showed that garlic has an excellent antihyperglycemic activity in addition to its lipid-lowering properties. The study also showed that garlic can reduce the levels of serum adenosine deaminase as well as C-reactive protein to help provide diabetic individuals with good glycemic control while at the same time help in the prevention of chronic or long-term complications such as diabetic neuropathies.

One of the principal indications of garlic oil is in the lowering of serum lipids to effect changes in cardiovascular and hemodynamic parameters. A study in 1993 by Jain, Vargas, Gotzkowsky, and McMahon showed that garlic powder tablets can decrease total cholesterol levels by as much as 6 percent and low density lipoprotein levels by as much as 11 percent. It was revealed that a dose of 900 mg per day can lead to such results within 12 weeks. The study was supported 20 years later in 2013 by Ried, Toben, and Fakler who posited that garlic preparations are an excellent alternative to cholesterol-lowering treatments such as statins because of their higher safety profiles. The study revealed that continued use of garlic preparations for at least 2 months can lead to reductions in total cholesterol levels by as much as 23 mg/dL and LDL cholesterol levels by as much as 15 mg/dL. Studies show that an 8 percent reduction in total cholesterol levels in the blood is already enough to bring about a 38 percent reduction in the risk of coronary artery diseases and events for individuals at least 50 years old.

Another very useful benefit of garlic essential oil is in its antihypertensive effects. In 2013, Ried, Frank, and Stocks conducted a dose-response trial on 79 hypertensive patients. The results showed that over a period of 8 weeks, patients with uncontrolled hypertension who took 4 garlic capsules daily showed a reduction in their blood pressure readings by as much as 7 mm Hg whereas those who took 2 garlic capsules daily for a period of 12 weeks showed significant blood pressure reductions by as much as 11.8 mm Hg. While the results are not as dramatic as mainstream antihypertensive medications such as beta-adrenergic blockers, calcium antagonists, diuretics, and angiotensin converting enzyme inhibitors, garlic essential oil has shown to be an excellent adjunct to conventional therapy for hypertension. The findings were supported by the 2014 study of Rohner, Ried, Sobenin, Bucher, and Nordman showing that, while the blood pressure-lowering effects of garlic preparations may be considered modest at best, they do provide a safer alternative to mainstream antihypertensive therapies. The blood pressure-lowering effect of garlic is largely attributed to the stimulation of the production of gasotransmitter hydrogen sulfide by the polysulfide contents of garlic. This helps stimulate the regulation and activity of nitric oxide to induce relaxation of the smooth muscle walls of the blood vessels leading to vasodilation and the reduction in arterial blood pressure.


Garlic is primarily used in the culinary arts. However, it does provide a host of healthier and more beneficial uses such as in the management of the following conditions.

Cardiovascular problems – hypertension, high cholesterol, hyperlipidemia, coronary artery disease, atherosclerosis, myocardial infarction, and heart attack

Infections – Escherichia coli infection, ear infections, tuberculosis, diphtheria, vaginal trichomoniasis, vaginal yeast infections, skin and nail infections, traveller’s diarrhea, influenza, common cold, hepatitis, H. pylori infections, bronchitis, and scalp ringworm

Musculoskeletal problems – muscle soreness, gout, and osteoarthritis

Digestive and metabolic problems – diabetes, diarrhea, liver disease, stomach ache, and hemorrhoids

Genitourinary problems – benign prostatic hyperplasia, menstrual disorders, and bloody urine 

Others – bladder and prostate cancer, cystic fibrosis, insect bites, chronic fatigue syndrome, and scleroderma.

Garlic is also used in the prevention of cancers of the colon, rectum, stomach, breast, prostate, and lungs as well as multiple myeloma.

Nutritional Information

Garlic is considered a superfood because it is packed with a lot of nutrients including Vitamin C and B-vitamins. It is also an excellent source of calcium, iron, magnesium, sodium, manganese, potassium, zinc, selenium, and phosphorus. Garlic also contains sulfur-based molecules that give it its excellent health benefits. These include allicin, s-allyl cysteine, and diallyl polysulfides. Additionally, garlic also contains flavonoids, enzymes, and saponins.

Side Effects

Except for its tendency to produce bad breath because of its pungent flavor, garlic is generally considered safe. For some individuals who are not accustomed to eating garlic, they may experience heartburn, nausea, gas, body odor, and even diarrhea. Some highly susceptible individuals have shown severe allergic reactions bordering that of asthma attacks.


1. Agarwal, K. C. (1996). Therapeutic actions of garlic constituents. Medicinal Research Reviews. 16(1): 111-124.
2. Ankri, S., and Mirelman, D. (1999). Antimicrobial properties of allicin from garlic. Microbes and Infection. 1(2): 125-129. 
3. Jain, A. K., Vargas, R., Gotzkowsky, S., and McMahon, F. G. (1993). Can garlic reduce levels of serum lipids? A controlled clinical study. The American Journal of Medicine. 94(6): 632-635. 
4. Kumar, R., Chhatwal, S., Arora, S., Sharma, S., and Singh, J., et al (2013). Antihyperglycemic, antihyperlipidemic, anti-inflammatory, and adenosine deaminase-lowering effects of garlic in patients with type 2 diabetes mellitus with obesity. Diabetes, Metabolic Syndrome, and Obesity: Targets and Therapy. 6: 49-56. 
5. Ried, K. and Fakler, P. (2014). Potential of garlic (Allium sativum) in lowering blood pressure: mechanisms of action and clinical relevance. Integrated Blood Pressure Control. 7: 71-82. 
6. Ried, K., Frank, O. R., and Stocks, n. P. (2013). Aged garlic extract reduces blood pressure in hypertensives: a dose-response trial. European Journal of Clinical Nutrition. 67, 64-70. 
7. Ried, K., Tobem, C., and Fakler, P. (2013). Effect of garlic on serum lipids: an updated meta-analysis. Nutrition Reviews. 71(5): 282-299. 
8. Rohner, A., Ried, K., Sobenin I. A., Bucher, H. C., and Nordman, A. J. (2014). A systematic review and meta-analysis on the effects of garlic preparations on blood pressure in individuals with hypertension. American Journal of Hypertension. 10.1093 
9. Sheela, C. G. and Augusti, K. t. (1992). Antidiabetic effects of S-allyl cysteine sulphoxide isolated from garlic Allium sativum Linn. Indian Journal of Experimental Biology. 30(6): 523-526. 
10. Taheri, M., Misaghi, A., Basti, A. A., Modaresi, M. H., and Dandomi, H., et al (2016). The effect of garlic (Allium sativum l.) essential oil on growth of E. coli O157:H7 and shiga toxin 2 production. Journal of Veterinary research. 71(1): Pe41-Pe47. 

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