The World's Healthiest Foods

Although garlic may not always bring good luck, protect against evil or ward off vampires, it is guaranteed to transform any meal into a bold, aromatic and healthy culinary experience.

Fresh, dried and powdered garlic are available in markets throughout the year, however, fresh varieties from California are in season from July through December.

Garlic is arranged in a head, called the “bulb,” averaging about 2 inches in height and diameter consisting of numerous small separate cloves. Both the cloves and the entire bulb are encased in paper-like sheathes that can be white, off-white or pinkish. Although garlic cloves have a firm texture, they can be easily cut or crushed. The taste of garlic is like no other - it hits the palate with a hot pungency that is shadowed by a very subtle background sweetness. While elephant garlic has larger cloves, it is more closely related to the leek and therefore does not offer the full health benefits of regular garlic.


Health Benefits

Whole books have been written about garlic, an herb affectionately called "the stinking rose" in light of its numerous therapeutic benefits. A member of the lily or Allium family, which also includes onions, garlic is rich in a variety of powerful sulfur-containing compounds including thiosulfinates (of which the best known compound is allicin), sulfoxides (among which the best known compound is alliin), and dithiins (in which the most researched compound is ajoene). While these compounds are responsible for garlic's characteristically pungent odor, they are also the source of many of its health-promoting effects. In addition, garlic is an excellent source of manganese, a very good source of vitamin B6 and vitamin C and a good source of selenium.

Cardiovascular Benefits

Numerous studies have demonstrated that regular consumption of garlic lowers blood pressure, and decreases platelet aggregation, serum triglycerides and LDL-cholesterol (the potentially dangerous form) levels while increasing serum HDL-cholesterol (the protective form) and fibrinolysis (the process through which the body breaks up blood clots), and stimulating the production of nitric oxide in the lining of blood vessel walls, which helps them to relax. As a result of these beneficial actions, garlic helps prevent atherosclerosis and diabetic heart disease, and reduces the risk of heart attack or stroke.

A study published in the November 2004 issue of Preventive Medicine shows that garlic also inhibits coronary artery calcification, a process that serves as a marker for plaque formation since the body lays down calcium in areas that have been damaged. In this year-long study, patients given aged garlic extract daily showed an average increase in their calcium score of 7.5%, while those in the placebo group had an average increase in calcium score of 22.2%.

One reason for garlic's beneficial effects may be its ability to lessen the amount of free radicals present in the bloodstream. According to a study published in the September 2004 issue of Life Sciences, a daily dose of 1 ml/kg body weight of garlic extract for six months resulted in a significant reduction in oxidant (free radical) stress in the blood of patients with atherosclerosis.

Since atherosclerotic plaques develop when cholesterol circulating in the bloodstream is damaged or oxidized, garlic's ability to prevent these oxidation reactions may explain some of its beneficial effects in atherosclerotic cardiovascular diseases. A German study published in November 2004 indicates that garlic also greatly reduces plaque deposition and size by preventing the formation of the initial complex that develops into an atherosclerotic plaque. Called "nanoplaque," it is formed when calcium binds to proteoheparan sulfate and then to LDL cholesterol. Garlic prevents the binding of calcium to proteoheparan sulfate, thus decisively inhibiting plaque generation.

Research presented at the 6th Annual Conference on Arteriosclerosis, Thrombosis and Vascular Biology held by the American Heart Association April 29, 2005 in Washington, D.C., suggests that garlic can help prevent and potentially reverse atherosclerotic plaque formation. The laboratory studies, conducted by well-known German scientist Professor Güaut;nter Siegel, M.D., from the University of Medicine in Berlin, Germany, found that powdered garlic (Kwai ® garlic) reduced the formation of nanoplaque (the first building blocks of atherosclerotic plaque) by up to 40% and reduced the size of the nanoplaque that did form by up to 20%.

Dr. Siegel s research shows that garlic acts in a manner similar to HDL (“good") cholesterol, which prevents the build-up of nanoplaques by hindering the docking of LDL (“bad" cholesterol) to its receptor sites in blood vessels or existing plaques.

Both garlic and HDL were able to reduce plaque formation and size within 30 minutes of incubation in these experiments. Existing plaques were dissolved by up to 25% within 15 minutes after the garlic was introduced, indicating a reversal of existing problems related to build-up of arterial plaque. In addition, calcification of the cholesterol docking sites in the arteries was reduced by up to 50% in the presence of the garlic extracts. (Calcium, although a vital mineral for bone formation and other essential physiological processes, is also one of the key factors involved in the formation of plaque.)

Garlic's numerous beneficial cardiovascular effects are due to not only its sulfur compounds, but its vitamin C, vitamin B6, selenium and manganese:

Garlic is a very good source of vitamin C, the body's primary antioxidant defender in all aqueous (water-solouble) areas, such as the bloodstream, where it protects LDL cholesterol from oxidation. Since it is the oxidized form of LDL cholesterol that initiates damage to blood vessel walls, reducing levels of oxidizing free radicals in the bloodstream can have a profound effect on preventing cardiovascular disease.

Garlic's vitamin B6 helps prevent heart disease via another mechanism: lowering levels of homocysteine. An intermediate product of an important cellular biochemical process called the methylation cycle, homocysteine can directly damage blood vessel walls.

The selenium in garlic not only helps prevent heart disease, but also provides protection against cancer and heavy metal toxicity. A cofactor of glutathione peroxidase (one of the body's most important internally produced antioxidants), selenium also works with vitmain E in a number of vital antioxidant systems. Since vitamin E is one of the body's top defenders in all fat-soluble areas, while vitamin C protects the water-soluble areas, garlic, which contains both nutrients, does a good job of covering all the bases.

Garlic is rich not only in selenium, but also in another trace mineral, manganese, which also functions as a cofactor in a number of other important antioxidant defense enzymes, for example, superoxide dismutase. Studies have found that in adults deficient in manganese, the level of HDL (the "good form" of cholesterol) is decreased.

Anti-Inflammatory, Anti-Bacterial and Anti-Viral Activity

Garlic, like onions, contains compounds that inhibit lipoxygenase and cyclooxygenase, (the enzymes that generate inflammatory prostaglandins and thromboxanes), thus markedly reducing inflammation. These anti-inflammatory compounds along with the vitamin C in garlic, especially fresh garlic, make it useful for helping to protect against severe attacks in some cases of asthma and may also help reduce the pain and inflammation of osteoarthritis and rheumatoid arthritis. In addition, allicin, one of the sulfur-compounds responsible for garlic's characteristic odor, is a powerful antibacterial and antiviral agent that joins forces with vitamin C to help kill harmful microbes. Allicin has been shown to be effective not only against common infections like colds, flu, stomach viruses, and Candida yeast, but also against powerful pathogenic microbes including tuberculosis and botulism.
Although garlic alone appears unable to prevent infection with Helicobacter pylori, the bacterium responsible for most peptic ulcers, frequently eating this richly flavored bulb may keep H. pylori from doing much damage. A study recently conducted at Faith University in Istanbul, Turkey, compared two groups containing 81 healthy individuals each. One group was selected from individuals who regularly ate lots of raw and/or cooked garlic, while the other group was composed of individuals who avoided it. For 19 months, blood samples were regularly collected from both groups and evaluated for the presence of H.pylori. While the incidence of H.pylori was pretty comparable—the bacterium was found in 79% of garlic eaters and 81% of those who avoided garlic—the garlic consuming group had a clear advantage in that antibodies to H.pylori were much lower in their blood compared to those who ate no garlic. (Antibodies are formed when the immune system reacts to anything it considers a potential pathogen, so less antibodies to H.pylori means less of the bacterium was present.) Among those who ate garlic, those who ate both raw and cooked garlic had even lower levels of antibodies than those who ate their garlic only raw or only cooked.

Laboratory studies recently conducted at the University of Munich, Germany, help explain why garlic may be such a potent remedy against the common cold. In these studies, garlic was found to significantly reduce the activity a chemical mediator of inflammation called nuclear transcription factor (NF) kappa-B.

NF kappa-B is itself activated as part of the immune system’s inflammatory response to invading organisms and damaged tissue. So, anything that sets off an inflammatory response –e.g. allergenic foods, a cold or other infection, physical trauma, excessive exercise, excessive consumption of foods containing high levels of omega 6 fatty acids (e.g., meat, corn or safflower oil) – can trigger a surge in NF kappa-B, which in turn not only promotes inflammation but sets up ideal conditions for viruses, including HIV, to replicate. In the blood samples tested in these just published German studies, unfertilized garlic caused a 25% drop in NF kappa-B activity, while sulfur-fertilized garlic lowered NF kappa-B activity by a very robust 41%!

Potent, Even Against Drug-Resistant Strains

Results of two recently published studies suggest that garlic is a potent antibiotic, even against strains that have become resistant to many drugs. One study conducted at the University of California Irvine Medical Center and published in the December 2003 issue of Nutrition showed that garlic juice, even when diluted up to 1:128 of the original juice, demonstrates significant antibacterial activity against a spectrum of pathogens including antibiotic-resistant strains such as methicillin- and ciprofloxacin-resistant staphylococci, vancomycin-resistant enterococci, and ciprofloxacin-resistant Pseudomonas aeruginosa. A second study found that garlic was able to inhibit methicillin-resistant Staphylococcus aureus (MSRA) from human patients that was injected into mice.(MSRA is one of the antibiotic resistant bacteria whose incidence has risen dramatically in recent years in hospitals.) Sixteen hours after the mice were infected, garlic extract, diallyl sulphide or diallyl disulphide (two of the active compounds found in garlic), was given orally. Twenty-four hours after they were infected, the mice were sacrificed and examined. Both garlic extract and its compounds were found to have exerted a number of protective actions against MSRA that significantly decreased the infection while also providing antioxidant protection in the blood, liver, kidney and spleen.

Cancer Protection

The organosulfur compound found in garlic called ajoene may also be useful in the treatment of skin cancer. In a study published in the July 2003 Archives of Dermatological Research, researchers applied ajoene topically to the tumors of patients with either nodular or superficial basal cell carcinoma, and in 17 of the 21 patients, the tumors shrunk significantly. Lab tests of the tumors before and after the application of ajoene revealed a significant decrease in Bcl-2, an apoptosis-suppressing protein. (Apoptosis is the self-destruct sequence used by the body to eliminate cancerous cells.)

Other studies have shown that as few as two or more servings of garlic a week may help protect against colon cancer. Substances found in garlic, such as allicin, have been shown to not only protect colon cells from the toxic effects of cancer-causing chemicals, but also to stop the growth of cancer cells once they develop. While more research is needed to confirm, recent animal research has also suggested that garlic may confer protection against the development of stomach cancer through its potential abilty to decrease H.pylori-induced gastritits. Cooking garlic with meat appears to reduce the production of carcinogenic chemicals that can occur in meat as a result of cooking methods, such as grilling, that expose meat to high temperatures. Good intakes of vitamin C and selenium, with which fresh garlic is well-endowed, are also associated with a reduced risk of colon cancer, making garlic a smart addition to any colon cancer prevention plan.

Diabetes Mellitus

Garlic may be able to help protect against a number of the most damaging degenerative effects of diabetes—retinopathy disease of the retina), nephropathy (kidney disease) and neuropathy (nervous system disease)—all of which are caused by an imbalance between the free radicals generated when blood sugar levels remain high and the body’s protective antioxidant defenses. A study published August 2003 showed that when diabetic rats were exposed to the cancer drug, streptozotocin, which would normally have produced not only a significant rise in blood sugar levels, but an increase in triglycerides, cholesterol, damaged fats, and other markers of increased inflammation, along with a decrease in the antioxidants the body produces to protect itself, that giving the rats garlic oil both lowered the drug’s negative effects while boosting protective antioxidant levels. The rats in this study were given 10 mg of garlic oil per kilogram of body weight daily for 15 days. In humans, a comparable dose of garlic oil would be .7 grams per day, an amount that could be easily consumed if using a garlic oil product, but would take real dedication if consuming cloves. Since a typical garlic clove weighs 3 grams and contains 15mg of total fat, which we can treat as basically synonymous with oil, this would translate to about 46 ½ cloves of garlic!

Protection Against Diabetes-Linked Cardiovascular Disease

Cardiovascular disease is a well-known side-effect of diabetes, but garlic may provide some protection, according to a study published December 2003. When diabetic rats were given garlic extract for an 8-week period, the hyperreactivity of their blood vessels to noradrenaline (a vasoconstrictive hormone) and acetylcholine (a compound involved in nerve transmission) was significantly lessened. According to the researchers, their results suggest that garlic may help prevent the development of abnormal vascular contraction seen in diabetics.

Weight Control

The most potent active constituent in garlic, allicin, has been shown to not only lower blood pressure, insulin and triglycerides in rats fed a fructose (sugar)-rich diet, but also to prevent weight gain, according to a study published in the December 2003 issue of the American Journal of Hypertension. In this study, after 5 weeks of being fed a high fructose diet consisting of 21% protein, 5% fat, 60% carbohydrate, 0.49% sodium and 0,49% potassium, male rats had developed high insulin levels, high blood pressure and high triglycerides. The rats were then divided into 3 groups for the remaining 5 weeks of the study: the first group served as a control; the second was given allicin during the final 2 weeks of the study, and the third was given allicin during the initial 3 weeks. Despite the fact that all three groups consumed the same amount of food, weight rose in the control group and in groups 2 and 3 when not receiving allicin, but remained stable or declined slightly when allicin was given. The researchers concluded that allicin may be of practical value for weight control.

Increased Antioxidant Protection

A study published in the November 2003 E-version of the journal Carcinogenesis showed that levels of a critically important internally produced antioxidant enzyme, glutathione-S-transferase, rose substantially in the stomach and small intestine, and to a lesser extent in the liver and colon, in rats that were put on a short-term feeding regimen that featured two compounds from garlic, diallyl disulfide and diallylthiosulfinate (allicin). Researchers discovered that these garlic compounds selectively induced two genes to produce more of the messenger RNAs (mRNAs) that encode glutathione-S-transferase, and the greatest increases were noted in mRNAs that are normally present only at low levels. The bottom line: eating more garlic may help increase your body’s production of this vitally important antioxidant enzyme.

Protection against Asbestos

Asbestos, a well known carcinogen, is thought to cause cell mutations by generating reactive oxygen species (free radicals) and depleting one of the body's most important internally produced antioxidants, glutathione. Garlic contains numerous sulfur compounds and glutathione precursors that act as antioxidants and also demonstrate anti-carcinogenic properties. In a laboratory study published in the November 2004 issue of Toxicology Letters, garlic extract, when administered along with asbestos, so significantly reduced DNA mutations in human blood lymphocytes (a type of immune cell), that the researchers concluded: "garlic extract may be an efficient, physiologically tolerable quencher of asbestos-induced genotoxcity."


For a small vegetable, garlic (Allium sativum) sure has a big, and well deserved, reputation. This member of the Lily family, a cousin to onions, leeks and chives, can transform any meal into a bold, aromatic and healthy culinary experience.

Garlic is arranged in a head, called the “bulb,” which is made up of separate cloves. Both the cloves and the entire bulb are encased in paper-like sheathes that can be white, off-white or pinkish.

Garlic cloves are off-white in color, and although they have a firm texture, they can be easily cut or crushed. The taste of garlic is like no other - it hits the palate with a hot pungency that is shadowed by a very subtle background sweetness.

The teardrop-shaped garlic bulbs range in size; however, they usually average around two inches in height and two inches in width at their widest point. While elephant garlic has larger cloves, it is more closely related to the leek and therefore does not offer the full health benefits of regular garlic.


Native to central Asia, garlic is one of the oldest cultivated plants in the world and has been grown for over 5000 years. Ancient Egyptians seem to have been the first to cultivate this plant that played an important role in their culture.

Garlic was not only bestowed with sacred qualities and placed in the tomb of Pharaohs, but it was given to the slaves that built the Pyramids to enhance their endurance and strength. This strength-enhancing quality was also honored by the ancient Greeks and Romans, civilizations in which athletes ate garlic before sporting events, and soldiers consumed it before going off to war.

Garlic was introduced into various regions throughout the globe by migrating cultural tribes and explorers. By the 6th century BC, garlic was known in both China and India, the latter country using it for therapeutic purposes.

Throughout the millennia, garlic has been a beloved plant in many cultures for both its culinary and medicinal properties. Over the last few years, it has gained unprecedented popularity since researchers have been scientifically validating its numerous health benefits.

Currently, China, South Korea, India, Spain and the United States are among the top commercial producers of garlic.

How to Select and Store

For maximum flavor and nutritional benefits, always purchase fresh garlic. Although garlic in flake, powder or paste form may be more convenient, you will derive less culinary and health benefits from these forms.

Purchase garlic that is plump and has unbroken skin. Gently squeeze the garlic bulb between your fingers to check that it feels firm and is not damp.

Avoid garlic that is soft, shriveled, moldy or that has begun to sprout. These may be indications of decay that will cause inferior flavor and texture. Size is often not an indication of quality. If your recipe calls for a large amount of garlic, remember that it is always easier to peel and chop a few larger cloves than many smaller ones. Fresh garlic is available in the market throughout the year.

Store fresh garlic in either an uncovered or a loosely covered container in a cool, dark place away from exposure to heat and sunlight. This will help maintain its maximum freshness and help prevent sprouting, which reduces its flavor and causes excess waste. It is not necessary to refrigerate garlic. Some people freeze peeled garlic; however, this process reduces its flavor profile and changes its texture.

Depending upon its age and variety, whole garlic bulbs will keep fresh from two weeks to two months. Inspect the bulb frequently and remove any cloves that appear to be dried out or moldy. Once you break the head of garlic, it greatly reduces its shelf life to just a few days.

How to Enjoy

Tips for Preparing Garlic:

The first step to using garlic (unless you are roasting the entire bulb) is to separate the individual cloves. An easy way to do this is to place the bulb on a cutting board or hard surface and gently, but firmly, apply pressure with the palm of your hand at an angle. This will cause the layers of skin that hold the bulb together to separate.

To separate the skin from the individual cloves, place a clove with the smooth side down on a cutting board and gently tap it with the flat side of a wide knife. You can then remove the skin either with your fingers or with a small knife. If there is a green sprout in the clove’s center, gently remove it since it is difficult to digest.

Chopping or crushing stimulates the enzymatic process that converts the phytochemical alliin into allicin, a compound to which many of garlic’s health benefits are attributed. In order to allow for maximal allicin production, wait several minutes before eating or cooking the garlic.

A Few Quick Serving Ideas:

Marinate pressed garlic in olive oil and use this flavored oil in dressings and marinades.

Purée fresh garlic, canned garbanzo beans, tahini, olive oil and lemon juice to make quick and easy hummus dip.

Healthy sauté steamed spinach, garlic, and fresh lemon juice.

Add garlic to sauces and soups.

Purée roasted garlic, cooked potatoes and olive oil together to make delicious garlic mashed potatoes. Season to taste.


Garlic is not a commonly allergenic food, is not known to contain measurable amounts of goitrogens, oxalates, or purines, and is also not included in the Environmental Working Group's 2003 report "Shopper's Guide to Pesticides in Produce" as one of the 12 foods most frequently containing pesticide residues.

Nutritional Profile

Introduction to Food Rating System Chart

The following chart shows the nutrients for which this food is either an excellent, very good or good source. Next to the nutrient name you will find the following information: the amount of the nutrient that is included in the noted serving of this food; the %Daily Value (DV) that that amount represents (similar to other information presented in the website, this DV is calculated for 25-50 year old healthy woman); the nutrient density rating; and, the food's World's Healthiest Foods Rating. Underneath the chart is a table that summarizes how the ratings were devised. For more detailed information on our Food and Recipe Rating System, please click here.


1.00 oz-wt
42.24 calories
Nutrient Amount DV
World's Healthiest
Foods Rating
manganese 0.47 mg 23.5 10.0 excellent
vitamin B6 (pyridoxine) 0.35 mg 17.5 7.5 very good
vitamin C 8.85 mg 14.8 6.3 very good
tryptophan 0.02 g 6.3 2.7 good
selenium 4.03 mcg 5.8 2.5 good
calcium 51.31 mg 5.1 2.2 good
phosphorus 43.38 mg 4.3 1.8 good
vitamin B1 (thiamin) 0.06 mg 4.0 1.7 good
copper 0.08 mg 4.0 1.7 good
protein 1.80 g 3.6 1.5 good
World's Healthiest
Foods Rating
excellent DV>=75% OR Density>=7.6 AND DV>=10%
very good DV>=50% OR Density>=3.4 AND DV>=5%
good DV>=25% OR Density>=1.5 AND DV>=2.5%


  • Adlercreutz H. Western diet and Western diseases: some hormonal and biochemical mechanisms and associations. Scand J Clin Lab Invest. 1990:50(S201):3-23.
  • American Botanical Council. New Research Supports Garlic's Role in Arresting and Reversing Arteriosclerosis. www., the e-newsletter of the American Botanical Council, April 29, 2005.
  • Andorfer JH, Tchaikovskaya T, Listowsky I. Selective expression of glutathione S-transferase genes in the murine gastrointestinal tract in response to dietary organosulfur compounds. Carcinogenesis 2003 Nov 21 [Epub ahead of print].
  • Anwar MM, Meki AR. . Oxidative stress in streptozotocin-induced diabetic rats: effects of garlic oil and melatonin. Comp Biochem Physiol A Mol Integr Physiol. Aug;135(4):539-547.
  • Baluchnejadmojarad T, Roghani M. Endothelium-dependent and -independent effect of aqueous extract of garlic on vascular reactivity on diabetic rats. Fitoterapia. 2003 Dec;74(7-8):630-7.
  • Bhattacharya K, Yadava S, Papp T, Schiffmann D, Rahman Q. Reduction of chrysotile asbestos-induced genotoxicity in human peripheral blood lymphocytes by garlic extract. Toxicol Lett. 2004 Nov 28;153(3):327-32.
  • Durak I, Aytac B, Atmaca Y, Devrim E, Avci A, Erol C, Oral D. Effects of garlic extract consumption on plasma and erythrocyte antioxidant parameters in atherosclerotic patients. Life Sci. 2004 Sep 3;75(16):1959-66.
  • Elkayam A, Mirelman D, Peleg E, Wilchek M, Miron T, Rabinkov A, Oron-Herman M, Rosenthal T. The effects of allicin on weight in fructose-induced hyperinsulinemic, hyperlipidemic, hypertensive rats. Am J Hypertens. 2003 Dec;16(12):1053-6.
  • Keiss HP, Dirsch VM, Hartung T, Haffner T, Trueman L, Auger J, Kahane R, Vollmar AM. Garlic (Allium sativum L.) modulates cytokine expression in lipopolysaccharide-activated human blood thereby inhibiting NF-kappaB activity. J Nutr. Jul;133(7):2171-5.
  • Lee YL, Cesario T, Wang Y, Shanbrom E, Thrupp L. Antibacterial activity of vegetables and juices. Nutrition. 2003 Nov-Dec;19(11-12):994-6.
  • Salih BA, Abasiyanik FM. Does regular garlic intake affect the prevalence of Helicobacter pylori in asymptomatic subjects. Saudi Med J. Aug;24(8):842-5.
  • Siegel G, Michel F, Ploch M, Rodriguez M, Malmsten M. [Inhibition of arteriosclerotic plaque development by garlic]. Wien Med Wochenschr. 2004 Nov;154(21-22):515-22.
  • Tilli CM, Stavast-Kooy AJ, Vuerstaek JD, Thissen MR, Krekels GA, Ramaekers FC, Neumann HA. The garlic-derived organosulfur component ajoene decreases basal cell carcinoma tumor size by inducing apoptosis. Arch Dermatol Res. Jul;295(3):117-23.
  • Tsao SM, Hsu CC, Yin MC. Garlic extract and two diallyl sulphides inhibit methicillin-resistant Staphylococcus aureus infection in BALB/cA mice. J Antimicrob Chemother. 2003 Dec;52(6):974-80. .

This page was updated on: 2005-07-16 22:44:31
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