encyclopedia

Garlic

Scientific Names:     

Allium sativum L. [Fam. Liliaceae]     

Forms:     

Fresh garlic; powdered and volatile oil extract; standardized allicin extracts.     

Traditional Usage:     

– Abnormal Growths Prevention
– AIDS
– Allergies (symptom reduction)
– Anti-aging
– Antibacterial
– Antifungal
– Anti-inflammatory
– Antimicrobial
– Antioxidant
– Anti-protozoal
– Antiseptic
– Anti-thrombotic
– Anti-viral
– Athlete's Foot
– Blood Sugar Control
– Bone and Joint Problems and Pain
– Breastfeeding Problems
– Bronchitis
– Burns (antiseptic poultice)
– Cellular Regeneration
– Circulation problems
– Cleansing
– Colds and flu
– Chronic catarrh (mucous)
– Detoxification
– Digestive problems
– Earache
– Fever
– Herpes Infection
– High cholesterol
– HIV Infection
– Hyperglycemia
– Immune System Strengthening
– Infections
– Memory
– Pneumonia
– Poultice
– Sinusitis
– Sore throat
– Sties (oral use – not topical)
– Tonsillitis (fresh garlic)
– Ulcers
– Vascular Disorders
– Worms
– Wounds
– Yeast infections     

Overview:     

Garlic, Allium sativum L. [Fam. Liliaceae], has been used as a medicine for over 5000 years by more cultures than perhaps any other plant. Originating in central Asia, it is now found in Europe, North Africa, Asia, and North America. Traditionally garlic has been a remedy for abnormal growths, bronchitis, pneumonia, digestive problems, intestinal infections, tuberculosis, dysentery, earaches and infections, vascular disorders of many kinds, and poor circulation. French priests used it against the bubonic plague and during WWI European soldiers applied it to their wounds. It was for this ability to prevent infection that garlic was known as Russian penicillin. Today garlic is popularly used against many of the world's most deadly diseases, particularly vascular disease and abnormal growths. The activity of garlic is mostly ascribed to sulfur compounds including the thiosulfinates, of which allicin is 70-80%. Lawson (1998) summarizes the medical studies on garlic up to 1996 as follows: antimicrobial effects (252 pharmacological/35 clinical); abnormal growth prevention/treatment (221/2, plus 10 epidemiological studies); effect on blood sugar levels (28/3); immune stimulation (15/3); anti-inflammatory (11/1); and antioxidant (28/3). Relative to vascular benefits: blood lipids (179/62, plus 2 epidemiological studies); vascular pressure (78/18); blood flow (51/18); blood platelet aggregation (76/6); and atherosclerosis (23/2). Lawson notes that numerous clinical trials with garlic cloves and standardized garlic powder tablets leave little doubt that modest amounts of garlic have significant vascular benefits by reducing serum cholesterol, vascular pressure and platelet aggregation. Epidemiological and animal studies strongly indicate significant activity against abnormal growths, particularly of the intestinal tract. And its intestinal and tropical antimicrobial activities are also well recognized. Garlic is one of the top non-prescription phytomedicines in Germany, where most of the clinical research has taken place, with 8% of the population regularly using supplements. Garlic is clearly an important medicine of the world.     

Active Ingredients:     

Garlic contains: Alliin (most abundant sulfur compound – ca. 10mg/g fresh weight or 30mg/g dry weight), the enzyme alliinase (ca. 10mg/g fresh – one of the two most abundant proteins in garlic that converts alliin to allicin); allicin (the main thiosulfinate in crushed garlic – ranging from 60-90%, typically 75%); other thiosulfinates, diallyl sulfide and other allyl sulfides; ajoene; vinyldthiins; S-allylcysteine; S-allyl-mercaptocysteine; and many other sulfur-containing compounds; amino acids; glycosides; vitamins; minerals; trace elements including selenium and germanium. Garlic also contains high levels of fructans (approximately 65% of dry weight), fructose polymers of 10-60 units, sometimes called 'pre-biotics' (fructans increase mineral absorption, support beneficial bifido-bacteria within the digestive tract and help to eliminate pathogenic gut bacteria and yeast). Fresh garlic is relatively low in moisture content (62-68%) compared to other foods (80-90% for most fruits and vegetables) and has a sulfur content of approximately 3mg/g – at least four times higher than other sulfur-rich foods like onions, broccoli, cauliflower and apricots. Garlic is also one of the highest selenium-containing foods on a per gram basis – and even more so when grown in a selenium-enriched soil.     

Suggested Amount:     

Fresh, minced garlic bulb: 2 to 4 grams two to three times daily.
Infusion: 4 grams in 150ml of water.
Capsules: 600 to 900 mg daily.
Standardized allicin extracts: 0.6-1.8g/day and/or follow manufacturer directions.
Tincture (1:5 in 45% alcohol): 2-4 ml three times daily.
Oil: 0.03 to 0.12 ml three times daily or 10 mg
Juice of Garlic: (BPC 1949) 2 to 4 ml.
Syrup of Garlic: (BPC) 2 to 8 ml.
 
A recommended safe level for consumption of fresh garlic is 10 grams (2-3 cloves or 3.3 grams dry weight) per day, eaten with meals. Several human studies have shown that long-term consumption of 10-15 grams (2-5 cloves) of fresh garlic daily produces no noticeable side effects, other than odor on breath and skin. No-odour garlic capsules are available to largely circumvent this problem; these use enteric coated capsules that only dissolve once past the area of the digestive tract that will lead to breath odor. (One fresh clove weighs approximately 2-4 grams). Since cooking prevents most of the allicin formation, considerably higher amounts of cooked garlic can be safely consumed.

Drug Interactions:     

Because of its blood-thinning effects do not take with anticoagulant medications or aspirin or before surgery. There may be a potential interaction between garlic and warfarin.     

Contraindications:     

The German Commission E reported that no contraindications were known. However, some sources recommend against using garlic with acute gastrointestinal inflammation or acute irritation. Others caution against using garlic prior to surgery to avoid increased bleeding time. If you have a blood-clotting disorder consult a physician before using concentrated garlic products. Safe to use during pregnancy and lactation but may cause colic in some infants. The World Health Organization (1999) notes that garlic is contraindicated in those individuals who have a known allergy to garlic.     

Side Effects:     

May cause mild stomach upset or irritation in some individuals. Take with food to avoid these effects. Other side effects include a burning sensation in the mouth and gastro-intestinal tract, nausea, diarrhea, and vomiting. Lawson reports that other side effects include skin allergies on the left hand from frequent slicing, skin burns when crushed cloves are placed on the skin for more than six or more hours (shorter times should be used for treating skin infections), and rare cases of asthma attacks from occupational exposure to garlic dust. Lawson also reports that allicin has an LD50 (lethal dose causing death of 50% of animals tested) of 60mg/kg bw (intravenously), corresponding to 1200 grams of fresh garlic for a 70 kg person.     

References:     

Blumenthal M, Goldberg A, Brinckmann J 2000. Herbal Medicine: Expanded Commission E Monographs. Copyright American Botanical Council. Publ. by Integrative Medicine Communications, 1029 Chestnut Street, Newton, MA 02464. Pp. 139-148.
 
Carper, J. 1993. Food Your Miracle Medicine. HarperCollins Publishers, 10 East 53rd Street, New York, New York 10022-5299.
 
Duke, J. 1997: The Green Pharmacy, The Ultimate Compendium of Natural Remedies from the World's Foremost Authority on Healing and Herbs. Rodale Press.
 
Lawson, LD. 1998. Garlic: A Review of its Medicinal Effects and Indicated Active Compounds. In: Lawson, LD. and R. Bauer (eds.). Phytomedicines of Europe: Chemistry and Biological Activity. Washington, DC: American Chemical Society Symposium Series 691. Pp. 176-209.
 
McCaleb, RS, Leigh, E, Morien, K. 2000. Garlic in The Encyclopedia of Popular Herbs. Publ. by Prima Publishing, 3000 Lava Ridge Court, Roseville, CA 95661.