Health Benefits Of Garlic Oil, Side Effects, And How To Use It
Watch as your skin, hair, and health improve with a few drops of this enriching oil.
Dr. Geeta Dharmatti is the Director and Founder of Geeta Nutriheal Consultancy (Nutrition Services Consultancy) and an Executive Member of the Indian Dietetic Association. She has done her Masters in Nutrition and PhD in Clinical Nutrition. Dr.
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Our ancestors were aware of many garlic oil benefits, which have since been passed down to us. Garlic has medicinal properties, so it’s not surprising that some of its therapeutic properties also trickled down to its oil.
Garlic (Allium sativum) is widely used in foods and seasonings worldwide. It belongs to the onion family.
Garlic oil is made by crushing garlic cloves and soaking them in vegetable oil. It is also made by steam distillation in large quantities. Garlic oil is recognized as offering many health benefits, including the potential to promote hair growth, boost heart health, and treat a variety of skin conditions.
This article discusses the benefits of garlic oil, its recommended dosage, how to use it for maximum benefits, and any potential side effects. Keep reading.
Know Your Ingredient: Garlic OilWhat Is It?
Garlic oil is extracted from cloves of garlic after soaking them in vegetable oil.
What Are Its Benefits?
This oil may help in promoting hair growth, treating fungal and viral infections, and healing wounds,
Who Can Consume It?
Anyone apart from those who take blood thinner can consume or use garlic oil.
How Often?
It is generally safe to consume garlic oil capsules in moderation or use a few drops of garlic oil mixed with a carrier oil, such as olive oil, once or twice daily.
Caution
Individuals who are allergic to garlic, and pregnant or breastfeeding women should consult a doctor before consumption of garlic oil.
In This Article
Garlic Oil: Origin And Importance
Garlic (Allium sativum L.) originated in Central Asia. Its plant has been used as a flavoring agent and traditional medicine since time immemorial. It is known not only for its flavor but also for its aid in digestion (1).
Garlic is used as a diuretic, diaphoretici A substance to induce excessive sweating. , expectoranti A medicine used to clear mucus from the airway to relieve congestion and treat cough. , and stimulanti Any substance that increases the activity of central nervous system. . The plant has been used to treat tuberculosisi A contagious infectious disease caused by Mycobacterium tuberculosis bacteria affecting the lungs. , cough, and cold in ancient medicine. Extracts of garlic have shown broad-spectrum antibacterial and antifungal activity as well (1).
In this article, we’ll be focusing on garlic oil. The essential oils of garlic have high amounts of sulfur-containing compounds. The medicinal properties of garlic have been attributed to its abundance of sulfur-containing compounds (1).
Additionally, garlic oil is known for its antifungal, antibacterial, antiparasitic, antiviral, and insecticidali A quality (of any substance) to destroy or control insects. properties (1).
TriviaCheck out the list of health benefits you can reap from this oil in the next section.
10 Benefits Of Garlic Oil For Health And Wellness
From clearing up a chronic ear infection to boosting your immunity, garlic oil offers many benefits. It may control hypertension, maintain blood pressure, and relieve toothache. Find out how and why below.
1. May Induce Hair Growth And Promote Strength
Alopecia or hair loss can occur due to multiple reasons. Genetic tendencies, environmental triggers, exposure to chemicals, medicines, oxidative stress, and prolonged illness are a few of them.
One trigger of alopecia that can be corrected is a nutritional deficiency (2).
Minerals like zinc, calcium, iron, copper, chromium, iodine, and magnesium are necessary for building hair fiber. Biotin, vitamin B (folic acid, pyridoxine, and pantothenic acidi Another name for Vitamin B, an essential nutrient. ), vitamin A, and vitamin E maintain the scalp and root health (2).
Supplementing them in your diet is the easiest way to stimulate hair growth. Spinach, broccoli, and garlic pods are rich in these micronutrients. Scientific studies suggest eating garlic or applying garlic oil can prevent hair loss (2), (3).
You can also use garlic for hair growth. Massaging with garlic oil may improve blood circulation to your scalp encouraging healthier growth. Due to its phytochemical composition, garlic oil exerts antibacterial activity as well. You can apply it directly to your scalp or crush a few garlic pods and mix them with yogurt to use as a mask (3).
2. Effective Remedy For Skin Diseases And Wounds
The oil and extracts of garlic have anti-inflammatory, antibacterial, fibrinolytic, and wound-healing properties that may make it a substitute for classic antibiotics and antiseptics and prove to be a great natural remedy (4).
Administering garlic oil to female rats reduced postoperative inflammation. The sulfur-containing compounds in garlic extracts accelerate the formation of new tissue and activate blood supply to open wounds (5).
Garlic extracts are also effective in healing a variety of skin conditions like atopic dermatitis, acne, psoriasis, fungal infections, scars, wrinkles, and other signs of aging (5).
3. May Promote Heart Health
Garlic oil has been found to reduce the risk of cardiovascular diseases. Its active component, diallyl disulfide, is responsible for its anti-atherosclerotic effects. It increases the fibrinolytic activity (prevents blood clots) in patients and healthy individuals (6).
Platelet aggregation is one of the first steps in the formation of blood clots. When these clots occur in your coronary or cerebral arteries, it can lead to myocardial infarction or ischemic stroke. A garlic-rich diet provides nutrition that can prevent platelet aggregation or thrombosis (7).
Garlic oil also increases the elasticity of blood vessels and circulation. Hence, it may lower the risk of cardiovascular diseases (CVDs) (6), (8).
4. May Heal Fungal Infection And Diseases
Experimental studies have shown that garlic oil has excellent antifungal activity. It inhibits the growth of fungal species like Candida albicans and Penicillium funiculosum (9).
Garlic oil can penetrate the membranes of fungal organelles. Microscopic observations have revealed that garlic oil damages fungal mitochondria and vacuoles. It alters the expression of certain essential genes that are involved in basic regulatory functions and pathogenicity of fungi (9).
Garlic oil and other garlic formulations can be used to treat candidiasis. Other fungal diseases, like tinea pedis (foot infection), superficial mycoses (skin infection), and otomycosis (ear infection), can also be addressed with this oil or extract (9), (5), (10).
5. May Have Immunity-boosting And Anti-inflammatory Effects
Garlic oil and other derivatives of garlic exhibit anti-inflammatory and immunomodulatory effects. It can suppress the production of pro-inflammatory cellular messengers like nitric oxide (NO), prostaglandins, and interleukins. Its sulfur compounds act on the immune system cells that trigger the production of such molecules (11).
Arachidonic acid is a precursor of several anti-inflammatory compounds, like prostaglandins. Garlic oil has been proven to be a potent inhibitor of arachidonic acid. It may also inhibit the enzymes involved in the synthesis of prostaglandins and other eicosanoids (11).
Animal studies have proven the immunomodulatory effects of garlic oil. Treatment with this oil reportedly shifts the balance of Th1 and Th2 cells towards Th2 cells.
While Th1 cells are responsible for the production of inflammatory compounds, the Th2 cells trigger the immune response (humoral or body) to douse the inflammation. This step involves antibodies and designated cells and brings about the anti-inflammatory effect (11).
6. May Prevent Neurodegenerative Diseases And Improve Brain Health
Distilled garlic oil contains various sulfur compounds, like diallyl disulfide (DADS) and diallyl trisulfide (DAT). These organic compounds prevent the oxidation and accumulation of cholesterol (12).
Lipid peroxidation is one of the critical factors behind aging. Excess cholesterol/lipids can get oxidized and form amyloid plaques or clots in the brain, heart, and bloodstream (12).
Amyloid plaques can narrow blood vessels and cause blood clots, which may ultimately cause neuron degeneration. Rapid neuronal cell death leads to memory loss or dementia. In later stages, it can lead to Alzheimer’s disease (AD), vascular dementia, and atherosclerosis (12).
7. May Calm Toothaches And Mouth Sores
Garlic is commonly used as a spice because of its medicinal properties. Chewing garlic pods releases the essential oils and phytochemicals into the oral cavity. These active elements can heal mouth sores, oral ulcers, sore gums, and toothache (13).
Garlic has broad-spectrum antibacterial, antiviral, and antifungal properties. Directly applying a paste made from garlic bulb on the affected teeth can relieve gingivitis (13).
It can also prevent the formation of dental plaque by inhibiting oral bacteria (Streptococcus mutans, S. sanguis, S. Salivarius, Pseudomonas aeruginosa, and Lactobacillus spp.) (13).
8. May Eliminate Enteric (Gut) Pathogens
Garlic oil demonstrates wide-spectrum antimicrobial activity against gut (enteric) pathogens. It can also inhibit enteric bacteria that cause food poisoning (14).
The allicin and other organosulfur compounds found in this oil are identified as the active ingredients that show inhibitory effects against Helicobacter pylori – gut pathogens that cause gastric cancer and several gastrointestinal (GI) disorders (14).
However, the antimicrobial activity may be reduced in the acidic enteric environment. This is probably why this property of garlic oil is not well-researched or documented (14).
9. May Possess Antiviral Activity
Garlic extracts exhibit antiviral activity. Human cytomegalo virus (HCMV), Influenza B virus, Herpes simplex virus type 1, Herpes simplex virus type 2, Parainfluenza virus type 3, vaccinia virus, vesicular stomatitis virus, and Human rhinovirus type 2 are a few viruses that are sensitive to these extracts (15).
Experiments have also proven that allicin-containing supplements can prevent bouts of the common cold. Ajoene, allicin, and allitridin are a few antiviral compounds found in garlic extracts.
They enhance the activity of NK-cells (natural killer-cells). These immune system cells destroy virus-infected cells (15).
Garlic phytochemicals also inactivate critical viral genes and enhance the production of neutralizing antibodies in your blood (15).
10. May Have Insecticidal And Acaricidal Properties
Garlic oil has been identified as a potent repellant. It shows an anti-feeding effect against blood-sucking parasites (hematophagous arthropods). Volunteers experienced about 97% protection from female feeding sandflies (Phlebotomus papatasi) bites when they applied garlic oil topically on the skin (16).
In another experiment, Culex quinquefasciatus mosquito larvae that were exposed to 5 ppm (parts per million, a unit of concentration) of diallyl disulfide in garlic oil were killed (100% mortality). However, some studies show garlic oil to be ineffective against adult mosquitoes (17).
Garlic oil also reduces the fecundity (ability to reproduce) of mites. Two-spotted spider mites, beetles, weevils, and other such species have been found to be susceptible to garlic oil. A few studies have proposed garlic oil to be a better acaricide than rosemary oil, jojoba oil, or a soybean-sunflower oil mix (17).
Like other garlic extracts, garlic oil can also work as a herbicide, nematicide, molluscicide, and algicide.
Above all, garlic oil is affirmed Generally Recognized As Safe (GRAS) as a food ingredient, seasoning, or flavoring by the US FDA (18).
In short, you can use garlic oil for cooking. It can work as a skin conditioner, hair tonic, antiviral and antibacterial agent, and pesticide.
Did You Know?
The source of garlic odor is the result of the conversion of the phytochemical alliin to allicin.
This conversion is brought about by the enzyme allinase. This enzymatic conversion takes place only on cutting or crushing the garlic pods.
Due to the intermediate step of enzymatic conversion, biochemists tend not to regard garlic oil as an ‘essential’ oil.
You must have come across many side effects of garlic. Does garlic oil have side effects as well? Let’s find out!
Does Garlic Oil Have Side Effects?
Though a lot of research has been done on the side effects of garlic, not a lot has been written or studied about the disadvantages of using garlic oil.
We certainly cannot presume it is entirely safe for us either. This is because garlic oil contains phytochemicals like allicin that are harmful to your liver (hepatotoxic) in large doses (17).
Evidence shows acute human health effects caused by these bioactive ingredients. A few of the symptoms include:
- Dermatitis
- Halitosis
- Asthma
- Coagulation dysfunction
- Cardiovascular disease or discomfort
- Gastrointestinal dysfunction
- Eczema
- Irritation to open wounds
Consuming whole garlic pods may also trigger adverse effects.
However, garlic and garlic oil are categorized as non-toxic substances. They are non-toxic to many people and repellent targets like birds and insects.
- While garlic oil offers many health benefits, certain people should take precautions. Much anecdotal evidence suggests that garlic oil may induce menstrual flow or cause digestive pain. So, pregnant women should speak with a healthcare provider before consuming it.
- Children can safely consume garlic oil in moderation, but it’s recommended to speak with a pediatrician before adding it to their diet, especially if it’s concentrated.
- People on anticoagulant medications, including warfarin, need to exercise caution since garlic oil may increase their effects and increase the risk of bleeding.
Also, garlic and garlic oil are not identified as carcinogens by the International Agency for Research on Cancer (IARC). This indicates that we can all (well, most of us) use garlic oil.
Fun FactHow do we use it so that it doesn’t elicit an adverse reaction? Find out the recommended dosage of garlic oil and tips to use it in the next section.
How To Use Garlic Oil? How Much Of It Is Recommended?
There is no particular set or recommended dose for using garlic oil. The safest option would be to consult a healthcare professional.
Discuss why you wish to use this oil. Weigh out the benefits and risks. Follow the dosage set by them for the best results.
Pure garlic oil is a product of the steam distillation of garlic. Although edible, it is regarded as unpalatable and has a pungent odor.
You can also make garlic oil at home. However, it is going to be a crude prep. More importantly, you might end up with ‘garlic-infused’ oil and not proper garlic oil.
Here’s the recipe for garlic oil.
How To Make Garlic Oil At Home
- Crush four cloves of garlic directly in a heated saucepan.
- Pour in half a cup (120 ml) of olive oil.
- Squeeze the cloves of garlic through a garlic press or a ladle directly into the pan. (You don’t need to peel the garlic before putting it in the press. The peel will remain in the press while you squeeze it.)
- Stir the garlic and olive oil together, so the garlic is evenly distributed in the pan.
- Heat the mixture over medium-low heat for 3 to 5 minutes.
- Cook the mixture, stirring it occasionally until the garlic is light brown and slightly crispy.
- Don’t let the oil come to a boil. A light simmer is enough. (Avoid overcooking the garlic. If it turns very dark, you’ve cooked it too long, and the oil will be bitter.)
- Remove the pan from the heat and pour the mixture into a container.
- Let the mixture cool down completely.
- If you don’t want tiny bits of garlic in your oil, you can strain it through a colander or sieve as you pour the mixture into the container. Leaving the garlic pieces in the oil will create a stronger flavor as it continues to infuse over time.
- Transfer the contents to an airtight container and seal it tightly.
- Keep the oil in the refrigerator for up to 5 days.
- Shake the container now and then to mix up the flavors.
You can also prepare garlic oil without cooking/roasting. It will take a little longer, though. Here’s what you need to do:
- Crush 8-10 medium-sized garlic cloves with the back of your knife.
- Peel the crushed pods. Use your hands to minimize the loss of oils.
- Transfer the crushed pods to a 0.5 to 1-liter glass jar with an airtight lid.
- Add about two cups (450-500 ml) of olive oil. (You can replace olive oil with an oil of your choice. You can also add herbs like rosemary, thyme, and parsley along with the garlic cloves for added aroma.)
- Seal the jar tightly and store it in the refrigerator for 2-5 days. Your bottle of garlic-infused herb oil is ready!
Caution
- Throw homemade garlic oil away after five days if you have not used it to be safe and avoid ingesting dangerous bacteria.
- Freeze the garlic oil for up to one year if you want it to last longer.
- Never store garlic oil at room temperature. It can cause botulism, a fatal form of food poisoning
- Soak garlic and herbs in 3% citric acid at room temperature for 24 hours. This way, the acid fully penetrates the ingredients and creates an unsuitable environment for the growth of botulism bacteria
Keep reading for more tips on storing these oils.
How To Store Garlic-Infused Oil
All vegetable oils retain quality better at cold temperatures and away from light.
Oils infused with herbs like basil, garlic, oregano, and rosemary can be safely stored at room temperature. However, oil flavor is maintained for a longer time if you store it in a refrigerator or freezer.
It is also best to protect infused oils from light. Store them in dark or amber-colored bottles. Make sure the bottles are clean and food grade.
A blogger shared a simple yet effective way of storing garlic in their blog. They wrote, “One way to store garlic is to slice or mince it and soak it in cooking oil. The result was amazing, as it lasted longer (even for months if you refrigerate it) (i).”
Infographic: Garlic Oil
Garlic oil is widely used in culinary delights and traditional home remedies. The volatile oil is produced by steam distilling garlic in ether, so it is full of garlic’s health benefits.
Check out the infographic below to learn more about garlic oil, its nutritional profile, and some ways to use this pungent condiment. Illustration: StyleCraze Design Team
Garlic has been used as a flavoring agent and an effective remedy for centuries. It can be consumed in many forms, and its oil has been proven to reduce the risk of heart diseases. The benefits of garlic oil can be attributed to its sulfur-containing compounds. It also exhibits antibacterial, anti-inflammatory, anti-fungal, and wound healing properties that help treat many ailments. Garlic oil may induce hair growth, promote heart health, fight against fungal infections, improve brain health, and calm toothaches and mouth sores. However, excess intake of garlic oil may be harmful to your liver due to the presence of allicin. It may also aggravate eczema, asthma, or dermatitis. Hence, use it in moderation to enjoy its benefits.
Frequently Asked Questions
Is garlic oil good for your skin?
Yes, garlic oil is good for your skin. Garlic possesses antifungal, antibacterial, antiviral, and antiseptic properties to treat various skin ailments.
Can I leave garlic on my face overnight?
No, garlic may cause skin irritation and burns if left on for a long time.
Is garlic good for anti-aging?
Yes, garlic is good for anti-aging. Garlic has strong antioxidants that can rejuvenate the skin.
Which is better for cholesterol: fish oil or garlic?
The combination of fish oil and garlic may help lower cholesterol and promote heart health. The combined benefits of fish oil and garlic have been studied. Overall cholesterol levels decreased in study participants after consuming fish oil and garlic for 60 days (19).
Key Takeaways
- The oil and extracts of garlic have anti-inflammatory and wound-healing properties.
- Garlic oil increases blood circulation and the elasticity of blood vessels, reducing the risk of heart diseases.
- Applying a garlic paste can relieve toothache and remove dental plaque.
- Always use garlic oil or consume garlic in moderation, as excessive intake might trigger adverse effects.
Illustration: Health Benefits Of Garlic Oil Side Effects And How To Use It
Image: Stable Diffusion/StyleCraze Design Team
References
Articles on StyleCraze are backed by verified information from peer-reviewed and academic research papers, reputed organizations, research institutions, and medical associations to ensure accuracy and relevance. Read our editorial policy to learn more.
- The Chemical Compositions of the Volatile Oils of Garlic (Allium sativum) and Wild Garlic (Allium vineale), Foods, US National Library of Medicine, National Institutes of Health.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5575638/ - ALOPECIA: HERBAL REMEDIES, International Journal of Pharmaceutical Sciences and Research, CiteSeerX, The Pennsylvania State Universit.
https://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.278.3702&rep=rep1&type=pdf - Ethnopharmacological survey of home remedies used for treatment of hair and scalp and their methods of preparation in the West Bank-Palestine, Research Article, BMC Complementary and Alternative Medicine, US National Library of Medicine, National Institutes of Health.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5499037/ - Effect of intraabdominal administration of Allium sativum (garlic) oil on postoperative peritoneal adhesion, European Journal of Obstetrics, Gynecology, and Reproductive Biology, US National Library of Medicine, National Institutes of Health.
https://pubmed.ncbi.nlm.nih.gov/24793933/ - Garlic in dermatology, Dermatology Reports, US National Library of Medicine, National Institutes of Health.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4211483/ - Garlic: a review of potential therapeutic effects, Avicenna Journal of Phytomedicine, US National Library of Medicine, National Institutes of Health.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4103721/ - Garlic and Organosulfur Compounds, Micronutrient Information Center, Linus Pauling Institute, Oregon State University.
https://lpi.oregonstate.edu/mic/food-beverages/garlic - A randomized trial of the effects of garlic oil upon coronary heart disease risk factors in trained male runners, Blood Coagulation & Fibrinolysis, US National Library of Medicine, National Institutes of Health.
https://pubmed.ncbi.nlm.nih.gov/11229829/ - Antifungal activity, kinetics and molecular mechanism of action of garlic oil against Candida albicans, Scientific Reports, US National Library of Medicine, National Institutes of Health.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4779998/ - Antifungal effects of Allium sativum (garlic) extract against the Aspergillus species involved in otomycosis, Letters in Applied Microbiology, US National Library of Medicine, National Institutes of Health.
https://pubmed.ncbi.nlm.nih.gov/7765862/ - The Immunomodulation and Anti-Inflammatory Effects of Garlic Organosulfur Compounds in Cancer Chemoprevention, Ani-Cancer Agets in Medicinal Chemistry, US National Library of Medicine, National Institutes of Health.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3915757/ - Neuroprotective Effects of Garlic A Review, Libyan Journal of Medicine, US National Library of Medicine, National Institutes of Health.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3074326/ - Ethnomedicinal Plants Used by Traditional Healers to Treat Oral Health Problems in Cameroon, Evidence-Based Complementary and Alternative Medicine, US National Library of Medicine, National Institutes of Health.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4606091/ - Antimicrobial Properties of Garlic Oil against Human Enteric Bacteria: Evaluation of Methodologies and Comparisons with Garlic Oil Sulfides and Garlic Powder, Applied and Environmental Microbiology, US National Library of Medicine, National Institutes of Health.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC92605/ - Therapeutic Uses and Pharmacological Properties of Garlic, Shallot, and Their Biologically Active Compounds, Iranian Journal of Basic Medical Sciences, US National Library of Medicine, National Institutes of Health.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3874089/ - Evaluation of repellent and anti-feeding effect of garlic oil (Allium sativum) against the bite of phlebotomine sandflies Diptera: Psychodidae, Annali dell’Istituto superiore di sanita., US National Library of Medicine, National Institutes of Health.
https://pubmed.ncbi.nlm.nih.gov/16244401/ - Garlic and Garlic Oil Profile, New York State Integrated Pest Management Program, Cornell Cooperative Extension.
https://ecommons.cornell.edu/server/api/core/bitstreams/935f15ae-c14b-47b2-8b82-898bc00f12cf/content - CFR – Code of Federal Regulations Title 21, U.S. Food & Drug Administration.
https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?fr=184.1317 - Effect of combined supplementation of fish oil with garlic pearls on the serum lipid profile in hypercholesterolemic subjects
https://pubmed.ncbi.nlm.nih.gov/16350679/
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