Garlic (Allium sativum)
By Krystal Thompson
Common Names: Camphor of the Poor, Poor Man’s Treacle, Rust Treacle, Stinking Rose, Russian penicillin
Description/Taxonomy: Garlic is a bulbous perennial herb in the Liliaceae/Allicaceae family, closely related to the onion. It has a tall, erect flowering stem that reaches 2-3 feet in height with pink or purple flowers that bloom in mid to late summer. Its leaves are long, narrow and flat like grass. The bulb (the only part of the plant that’s used) consists of numerous bulblets or cloves, grouped together between membrane-like scales or sheaths and enclosed within a whitish, papery skin that holds them together like a sac (5).
History, Ethnobotany, and Folklore: The name Allium sativum is derived from the Celtic word all, meaning burning or stinging, and the Latin sativum meaning planted or cultivated. The English name is derived from Anglo-Saxon gar-leac, meaning spear plant (in reference to the shape of its leaves).
Garlic has been prized for its culinary, medicinal, and spiritual benefits for millennia. In fact, its history and timeline as a cultivated plant is so vast that it’s hard to pinpoint its era or country of origin. Ancient Egyptians used it as a form of currency, and its medicinal benefits have been found transcribed on ancient temple walls and on papyrus dating back to 1500 BC (3). According to Pliny, both garlic and onion were called upon as deities by the Egyptians at the taking of oaths (5). Garlic is known to have been in the ancient repertoire of famous Greek healers such as Hippocrates and Galen, the latter responsible for the urge that the healer should above all else strive to “Do No Harm.”
Spiritually, garlic was prized as a protective agent. This is perhaps the origin of our common association (even presently) with garlic as a deterrent to vampires. It was one of several plants in ancient Greece that was worn to guard against illness and negative energies, including theft and possession by evil spirits. Both sailors and soldiers were known to wear protective cloves, both for spiritual protection and in case of sickness (8).
Arabian herbalists use garlic to respond to abdominal pain, infantile colic, diarrhea, diabetes, eye infections, snake bites, and even tuberculosis (3). The latter was a common use in 1800’s America: physicians recommended garlic inhalation as a treatment for TB (3). African herbalists use garlic to treat respiratory and helminthic (large worm-like parasites) infections, as well as garlic oil in drops to respond to childhood ear infections (3).
In 1858, Louis Pasteur (the French chemist and microbiologist who discovered the process that we know as pasteurization) put much public attention onto garlic by demonstrating its antiseptic and antibiotic activity in laboratory conditions. During World War I, garlic poultices were used to prevent wound infections, and by WWII the plant had a reputation as “Russian penicillin.” It was literally a lifesaver in times when antibiotics were in very short supply, so much so that various governments offered direct subsidy of garlic production by the ton after the war.
These demonstrations would pave the way for countless studies of garlic’s efficacy in such cases. Noteworthy published results include: 1) juice of raw garlic being effective against many common pathogenic intestinal bacteria (responsible for diarrhea in humans and animals), 2) efficacy even against those strains that are antibiotic resistant, 3) combination of garlic with antibiotics providing partial or sometimes total synergism, 4) repeated demonstrations of microorganism’s complete lack of resistance to garlic, 5) even toxin production by microorganisms- such as that released by candida when attacked- prevented by garlic (4).
American physicians actually relied on garlic specifically as an antihypertensive agent up until the late 1950’s when potent pharmaceuticals became more widely available, though it remained and is still a favorite of herbalists (4). In fact, in 1994 American herbalist Paul Bergner ran a survey of contemporary herbalists via his Medical Herbalism journal to find out which herbs they used and prescribed most often. Garlic ranked seventh out of the top fifty!
Parts Used: Bulb.
Cultivation and Harvest: Though it’s impossible to say for sure, garlic cultivation is thought to have originated in central Asia. The most specific location offering I found was “southwest of Siberia.” It has been cultivated in the Middle East for over 5,000 years, making it one of the earliest known cultivated plants. At some point it spread to Europe where it was naturalized, and can now be found wild in parts of Italy. Dumas described the air of Provence as being “particularly perfumed by the refined essence of this mystically attractive bulb” (5). Garlic plants are propogated by separating and planting individual bulbs. Selenium, a highly bioavailable trace mineral, is highly prized in medicinal garlic and many growers will add it directly to the soil to boost their harvest’s content (3).
Cloves are harvested in the fall as the flowers are replaced by a cluster of black seeds and the stalks begin to wither (3). Gilroy, California (just south of San Jose) claims to be the garlic capital of the world- the epicenter of the highest garlic-producing state in the US. Having been in Gilroy during their annual Garlic Festival (no joke), I believe they’ve earned their claim. China is also a massive producer of garlic.
Herbal Actions: Antihelmintic: kills intestinal worms. Anti-asthmatic: eases constricted breathing caused by asthma. Antilipemic: promotes a reduction of lipid levels in the blood. Anti-epileptic: reduces frequency or severity of convulsions. Anti-hypertensive: benefits high blood pressure. Antimicrobial: kills microorganisms or inhibits their growth. Antiseptic: reduces the possibility of infection, sepsis, and/or putrefaction. Antispasmodic: combats cramping and spasmodic pains, particularly in the digestive tract. Antiviral: fights viral infections. Aphrodisiac: stimulates sexual desire. Carminative: helps to expel gas. Diaphoretic: induces sweating. Emmenagogue: promotes menstruation. Expectorant: helps to expel mucuous.
Constituents: One of garlic’s primary constituents is allinase, an enzyme that is released and begins its metabolization process when the clove cells are crushed or broken (1). This breakdown happens at room temperature within a few hours, or within minutes during cooking (3). So remember to cut, crush, or bruise your garlic before use! Garlic also contains sulfur compounds, other enzymes, amino acids, and trace minerals such as selenium, which in combination with the sulfur compounds is thought to account for much of garlic’s anti-cancer and antioxidant effects. Garlic contains higher concentrations of sulfur compounds than any other Allium- these are responsible for both its pungent odor and many of its medicinal effects (3).
Energetics: Warm, bitter.
Meridians/Organs Affected: Large Intestine, Spleen, Stomach.
Medicinal Use: Medicinally, there is much attention on garlic. In this age of overly salted, sugared, and fat-soaked diets, herbs and spices that can benefit us without requiring massive lifestyle changes tend to be at the forefront of modern medicinal conversation. Luckily for us herbalists, that means increased funding being funneled into studying the herbs that we already know and rely on. Garlic has an incredibly impressive list of benefits, but let’s start with the heart.
Garlic is an ally for hypertension (high blood pressure); studies have shown a modest but undeniable decrease in blood pressure after four weeks of use (1). This happens via an activation of substances such as nitric oxide to relax smooth muscle cells and vasodilate blood vessels. It also “changes the membrane potential of vascular smooth muscle cells by opening potassium channels, causing vasodilation by keeping the calcium channel closed for a longer period of time” (1). Without contraindications, the German Commission recommends garlic as a supportive dietary measure to lower elevated blood lipids and as a preventative measure for age-dependent vascular changes (3).
Also in cardiovascular considerations, garlic use can benefit those with high cholesterol. Pooled data from various studies suggest that garlic can lower total cholesterol concentrations by up to 10% and favorably alters good and bad cholesterol ratios (3). In his 1996 book The Healing Power of Garlic, Paul Bergner notes that “in a head-to-head trial comparing garlic against the cholesterol-lowering drug bezafibrate, garlic was just as effective” (7). Garlic also acts as an anticoagulant by inhibiting the arachidonic acid cascade, a necessary but sometimes harmful conversion of fatty acids into biological mediators (2). Basically, garlic benefits blood clots.
Garlic offers significant antimicrobial action. Dr. Tariq Abdullah, a prominent garlic researcher, stated in the August 1987 issue of Prevention magazine that “garlic has the broadest spectrum of any antimicrobial substance that we know of” (6)! Studies have demonstrated garlic’s antibiotic activity against E coli, MRSA, and Salmonella in alcohol, oil, and water extracts (1). The alcohol and water preparations would be used internally, the oil on its own or as a topical base for an antibacterial salve. Additionally, a peeled garlic clove wrapped in gauze to prevent burning could be affixed to the bottom of a fungal infected food, or used as an overnight vaginal suppository to fight yeast infection (9). Garlic has also been found to be effective against anthrax and has been used to prevent such outbreaks in cattle (5).
In addition to battling bacteria, viruses, fungi, and other microorganisms, garlic stimulates the body’s natural defense against these invaders, making it a great post and preventative choice. It has also demonstrated success in supporting the immune system of AIDS patients, and in mice trials has prevented the toxic effects of mercury (9).
Some cancer research has shifted its gaze toward garlic lately as well. Studies have shown that increased dietary (not supplemental) garlic is correlated with a decreased risk of developing stomach, colon, and prostate cancer (1). The occurence of stomach cancer is markedly lower in populations with a high intake of allium vegetables. Studies have further demonstrated in vitro that H. pylori (a bacterium implicated in the causation of stomach cancer and ulcers) is susceptible to garlic at a fairly moderate concentration, including some antibiotic-resistant strains (4).
In TCM, garlic is known as da suan, and is used commonly to support high blood pressure, as a mild anticoagulant, and to respond to parasitic infections and food poisoning. It is traditionally contraindicated in patients with a yin deficiency (3). In Ayurveda, garlic is known as rasoon (meaning “lacking one taste”) or lasunam. It is used in response to respiratory problems, ulcers, colic and flatulence, and offers balance to the cooler vata and kapha constitutions (9).
Considered “forbidden food” for monks and those committed to celibacy, garlic is a powerful aphrodisiac. Ayurvedic practitioner KP Khalsa says he would actually rank it as the number one choice. He wrote, “It has all the qualities you would want in a sexual enhancer. It increases circulation and promotes erectile force, as well as increasing desire” (9). Onion apparently has similar, though much milder effects.
Allies: Garlic is the base of many homemade wellness concoctions such as fire cider and four thieves vinegar. In these recipes you’ll often find it paired with other herbs such as rosemary, ginger, chilis, cloves, wormwood, sage, cloves, etc. In addition to these, garlic pairs especially well with other pungent herbs such as cinnamon and thyme for thinning and expelling mucus (9).
Cautions and Contraindications: Though it poses some pharmaceutical interaction problems (as is the case with many herbs), garlic is generally considered safe. Other than inherent allergies or sensitivities to the plant, the primary threat that garlic could pose on a medication-free person is an increased risk of post-operative bleeding due to its anticoagulant properties. Any side effects would likely be minor and are dosage-dependent, but some people may experience heartburn, flatulence, or gastrointestinal irritation after consuming garlic. Prolonged topical use can also cause moderate burns.
Dosage and Method of Delivery: Garlic is one of the many powerful herbs that the general public now has access to in standardized supplement form, but it is important to note that odorless garlic supplements do not contain the primary active compounds. Read: they are the equivalent of garlic sugar pills. If you’re using garlic for its medicinal benefit, you’re much better off to accept the stink. Unless you’re taking copious amounts, the garlic aroma from taking supplements will be mild to undetectable.
Garlic syrup is a great way to reap the benefits of garlic and is fantastic in cases of asthma, coughs, chronic bronchitis, and various disorders of the lungs. Make your own by pouring a quart of boiling water over a pound of fresh cut cloves, and allow to stand in a covered vessel for twelve hours. Reheat, adding sugar until a syrupy consistency is achieved. Caraway and bruised fennel can be heated for a short time in vinegar and added to the garlic syrup, to both cover some of the pungent smell and add some extra expectorant benefit.
Tincture preparation is 1:1 and medicinal dosage is between 120-250 drops (9). For fungal response, a typical dose is three cloves per day or 6-9 capsules (9). A few cloves per day is a common dose for food preparations and/or gentle, tonic use.
As always, please check with your qualified healthcare professional for specific dosage guidelines and recommendations.
1. Sanchez, Phillip D. Garlic (Allium sativum), University of Colorado, Denver. Accessed online June, 2016.
2. Ekstrom, Gunilla. Inflammation Research, orexo.com. Accessed online June, 2016.
3. Kemper, Kathi J. Garlic (Allium sativum). The Longwood Herbal Task Force and The Center for Holistic Pediatric Education and Research, 2000.
4. Protection against Helicobacter pylori and other bacterial infections by garlic. Bastyr University, Washington, 2001.
5. Grieve, Maud. A Modern Herbal. Dover Publications, 1931.
6. Bergner, Paul. “Allium sativum: Antibiotic and Immune Properties.” Medical Herbalism: Journal for the Clinical Practitioner, 1995.
7. Bergner, Paul. The Healing Power of Garlic. Prima Publishing, 1996.
8. Cunningham, S. Cunningham’s Encyclopedia of Magical Herbs. Llewellyn Publications, 2000.
9. Khalsa Singh KP, Tierra M. The Way of Ayurvedic Herbs. Lotus Press, 2008.