GARLIC:
Garlic (Allium sativum) is a perennial plant native to Asia, and a member of the lily family. Though it is referred to as the "stinking rose", garlic is an essential ingredient in many types of cuisine around the world.
The history of garlic dates back to approximately 2300 B.C. in ancient Sumeria, and throughout this time, garlic has been used for its antiseptic and antibacterial qualities. When Egyptian medical papers were found dating back to 1550 B.C., they contained eight hundred formulas for the therapeutic uses of garlic. More recently, the famous French chemist, Louis Pasteur, found that garlic was an antibacterial agent.
People have, for thousands of years, used garlic to expel parasitic worms that lodge in the intestinal tract. Some studies show that garlic has an ability to kill amoeba and hookworms. In recent years, Indian studies have demonstrated that garlic has fibrinolytic activity. Fibrin is a protein necessary in clot formation. The protein is essential in the body, but when it exists in excess, there is an increased chance of clots disrupting blood flow. Garlic may have the ability to dissolve fibrin, in a process called fibrinolysis. Garlic has also demonstrated the ability to inhibit fibrinogen receptors on platelets. This is caused by the compound ajoene, which is a major component in garlic.
The Chemistry of Garlic
Today, much more is known about garlic due to advances in the field of organic chemistry. Many individual compounds have been analyzed and tested for their biological values. When garlic is crushed, it releases at least one hundred sulfur-containing compounds, and it is sulfur that gives garlic its distinctive odor.
The best method for using garlic in your diet is to cut or crush the raw clove. When garlic is crushed, it releases an enzyme called allinase, and this enzyme converts alliin, the substance in raw garlic, to allicin. Allicin is an extremely active substituent of garlic. When three allicin molecules combine, they form a compound called ajoene, which has antithrombotic (anti-clotting) properties. This means that it can prevent platelets (the blood cells involved in clotting) from clumping, which is what leads to blood clots.
Minerals in garlic Garlic also contains the minerals selenium and germanium. The amount of selenium in the bulb depends on the content of selenium in the soil where the bulb is grown. Selenium is a very important mineral because it is part of an enzyme in the body known as glutathione peroxidase. This enzyme helps deactivate some harmful substances that are created when we fight infections. When white blood cells become activated to fight a foreign substance in the body, they produce a toxic compound called hydrogen peroxide. Glutathione peroxidase helps to detoxify the body by converting hydrogen peroxides into water.
Glutathione peroxidase also uses its detoxifying properties to convert harmful lipid peroxides into less harmful substances. These toxic compounds are formed when fatty acids in the blood stream are attacked by harmful free radicals.
The Healing Power of Garlic
Research studies demonstrate that garlic is effective in healing the body in a number of ways: Garlic is effective in the destruction of Candida albicans, a fungus responsible for the dreaded yeast infection. Garlic also appears to stimulate NK cells and macrophages. These immune cells kill pathogens and abnormal cells in the body. Garlic has many sulfur compounds in its makeup, one of which is ajoene, which has antifungal properties. Garlic has also demonstrated an ability to inhibit bacteria by interfering with certain chemical reactions in the body. The sulfur compounds in garlic destroy thiol groups (sulfur - hydrogen groups) in the enzymes needed for reproduction of bacteria. Specifically, they interfere with DNA polymerases. These enzymes are needed for the replication of the bacterial chromosomes and this disruption will lead to the inability of the bacteria to reproduce. Garlic also has the ability to lower serum cholesterol. In some studies, it has been demonstrated that garlic can raise the level of "good cholesterol" in the body by at least eight percent. Another favorable aspect of fresh garlic is that it can reduce systolic blood pressure (the top number of blood pressure), and it has been shown to reduce triglycerides in the blood. Garlic also contains small amounts of vitamins A, B, C and E, and the minerals potassium, phosphorus, calcium, sodium, and iron. Not only does garlic reduce systolic blood pressure, it also has the ability to lower blood sugar, which makes it a very useful dietary tool in the treatment of diabetes. If you are hypoglycemic (low blood sugar), you will need to determine if garlic lowers your blood sugar too significantly. As with any substance, each individual is different, and therapeutic amounts must be individualized.
A Warning About Garlic and Blood Thinning Medications
People taking blood-thinning drugs, such as Ticlopidine or Coumadin, must use caution when using garlic. Garlic, with its anti-clotting properties, may react badly with these categories of drugs, and result in excessive bleeding. Not enough is known yet about the interaction between garlic and these drugs, so those people on blood thinners should not use standardized garlic extracts in excess of one-half clove of garlic daily.
Garlic has many healing attributes in its favor. It is antifungal, antibacterial which means it will help to heal athletes foot, jock itch and ringworm by taking it internally and externally It can also assist with the healing of a yeast infection. Warm garlic oil helps to heal an earache caused by bacteria.
Besides warding off vampires it can also fend off a cold,
flu or sore throat due to its allicin content.
Alliin is a complex sulfur compound that is changed to allicin by crushing. It's
like magic! Pop some fresh garlic in your mouth, crush it with your teeth and
natures takes the signal to change the alliin into allicin so the healing can
begin.
Research is showing promising results in garlic's ability to fight off cancer cells, especially the cells that attack the digestive system, the breast, and the prostate gland. A chemical called allyl sulfide is thought to be responsible for the cancer fighting ability.
Garlic also has the ability to make your blood thinner and less sticky which means it helps to prevent the platelets from building plaque up in your arteries. This helps to maintain the flexibility of the arteries in the heart. That means that the heart won't have to work so hard to do a normal job.
Allium sativum, commonly called garlic, is a bulb-forming herb of the Liliaceae (lily family). Its medical use traces back to 5,000 years ago in Asia where it was used by nomadic tribes to ward off evil spirits and improve health (Aaron, 1996). The ancient Egyptians, Greeks, and Romans praised and used garlic. Hippocrates recommended its use to combat constipation and as a diuretic. Aristotle suggested its use for a cure against rabies (Anon., 1997a). It was believed to give strength to the men who built the pyramids, courage to the Roman armies, and fighting spirit to the English gamecocks (Dobelis, 1990). During the early 1900s and the outset of World War I, British army surgeons used garlic as a bactericide (Anon, 1997a).
Like most plants, garlic contains more than 100 biologically useful secondary metabolites including alliin, alliinase, allicin, S-allycystein, diallylsulfide, and allymethyltrisulfide (Challem, 1995). The oil of garlic contains the amino acid alliin which, once the bulbs are crushed, is converted to allicin (Dreidger, 1996). The enzyme alline lyase catalyses the formation of allicin, which is in turn the precursor to several sulfur-containing compounds responsible for the flavor, odor, and pharmacological properties of garlic (Ellmore and Fekldberg, 1994).
Once exposed to air, allicin is further converted to diallyldisulfide which has antibacterial effects (Mabey, et al., 1988). Reduction by cysteine will disrupt the disulfide bond in microbial proteins. Prescriptions containing extracts of Allium sativum, either used alone or with amphotericin B, have effects against human systemic fungal infections and cryptococcal meningitis (Howe, 1997). Ajoene, another sulfer-containing compound found in garlic oil, also decreases bacterial growth in gram negative and positive bacteria and yeast (Naganawa, et al., 1996). Ajoene is not found in commercial garlic preparations, it is only found in small quantities in the natural oil (Ishikawa et al., 1996).
The Ames test revealed that ajoene inhibits mutagenesis induced by both benzo[a]pyreded (B[a]P) and 4-nitro-1,2-phenylenediamine (Ishikawa et. al., 1996). The inhibitions of mutagenesis by ajoene is especially effective for transition-type mutations (Agarwal, 1996).
Garlic has been shown to reduce blood clotting and to reduce blood pressure, therefore making it an important part of the treatment for cardiovascular disease (Mabey, et. al., 1988). Allicin and adrenosine are the most potent antiplatelet constituents of garlic because of their in vitro effects (Agarwal, 1996). Garlic oil administered to healthy students and patients with coronary artery disease (CAD) inhibited platelet aggregation in vivo. Low doses of garlic also appear to be effective over a long term administration (Bordia et. al., 1996). Dithiins and ajoenes possess antithrombic properties (Passwater, 1997). Ajoene is currently being developed as a drug for the treatment of thromboembolic disorders (Agarwal, 1996). Dithiin and ajoenes decrease clotting time because they are anticoagulants and thin blood. This activity indirectly reduces the risk of stroke and cardiovascular disease.
Garlic improves cardiovascular function because it provides protection against hypercholesterolemic, artherosclerosis, ischemia-reperfusion-induced, arrhythmias and infarctions. Oxygen-free radical have been implicated as causative factors in these diseases and antioxidants have been shown to effectively treat these conditions because it scavenges free radicals (Prasad et. al., 1996).
Potent enzymes that inhibit the activities of adenosine deaminase and cyclic AMP phosphodiesterase have been identified from garlic extracts. The presence of such enzyme inhibitors in garlic may perhaps explain its effect as an antithrombotic, vasodilatory, and anticancer combatant (Agarwal, 1996). Many of the therapeutic actions of garlic parallel the physiological effects of nitric oxide and may be explained by its ability to increase nitric oxide synthase activity intracellularly (Das et. al., 1995).
Allium sativum has shown significant effects on cancers that affect the stomach and intestine. Persons who regularly ingest garlic have lower incidence of stomach cancer (Anon., 1994b). The Chinese Academy of Medical Sciences reports that epidemiological studies show that dietary intake of garlic is inversely related to gastric cancers (Howe, 1997).
Diallytrisulfide (DATS) is a compound in garlic that lowers the spread of human lung cancer cells. DATS is extremely effective in reducing growth of human lung carcinoma cells in culture. Also, two other compounds in garlic have anticarcinogenic properties: S-allycysteine (SAC) and diallyldisulfide (DADS) (Anon., 1997c).
Garlic stimulates the immune system. The garlic stimulates the activity of macrophages and bulbs increase the activity of helper T cells. It is also effective in treating upper respiratory viral infections and protects cell membranes from DNA damage (Holladay, 1997).
Although there are some negative effects noted in the literature, most are case studies, and some epidemiological surveys. For one, 38 cases of botulism appeared from a restaurant which pointed to a commercially chopped garlic in soybean oil (St. Louis et al., 1988). Another anecdotal occurrence involved over-usage of garlic. A case of spontaneous spinal epidural hematoma associated with platelet dysfunction from excessive garlic ingestion (Rose et. al., 1990). Other ailments pinned to garlic include a contact dermatitis allergy (Delaney & Donnely, 1996; Burden et al., 1994), and possibly occupational asthma caused by aromatic herbs or garlic powder (Lemiere, 1996). There are more severe links that have been implied such as cancer (which is against intuition because it has been an anti-cancer agent). But, the connection is very indirect: the mouthwash used to cover-up the garlic smell seems to be the cause of the increase (Kabat et. al., 1989). There has been recent concern has been raised stemming from new analysis of cancer concern that ancillary compounds that have in effect been ignored may be affiliated with overall cancer rates (Davis, 1989). The most indicting data from a scientific viewpoint comes from a true experiment that was conducted on primary rat hepatocytes. The finding show that while garlic was beneficial for detoxification and antioxidation at 1mM of extract, treatment at 5mM was associated with a significant decrease in cell viability, significant morphology changes, and lowered activity (Sheen et al., 1996). There have been a number of negative aspects that have been correlated to garlic, but most come as anecdotal evidence or as preliminary data.
Compared to the minute evidence against garlic, the positive effects are overwhelming in number and strength. As more research is conducted, it may soon be classified next to ginseng as a panacea at the present rate of positive discoveries being made
Garlic supplements have an important part to play in the treatment of high cholesterol. Overall a 12% reduction in total cholesterol was shown over a placebo and that this reduction was normally evident after only 4 weeks treatment and that this was likely to persist for as long as the study was in progress.
New research shows that taking garlic during pregnancy can cut the risk of pre-eclampsia (raised blood pressure and protein retained in the urine). Studies reveal that garlic may help to boost the birth-weight of babies destined to be too small. The research was carried out by Dr D Sooranna, Ms J Hirani and Dr I Das in the Academic Department of Obstertrics & Gynaecology at the Chelsea & Westminster Hospital in London UK.
They concluded that although pre-eclampsia and growth retardation are complex
multifactoral conditions, taking standardised garlic tablets throughout pregnancy may decrease the chances of
these types of complictions at birth. They focussed on growth retarded babies
and pre-eclampsia, a potentially dangerous condition for mother and baby which
occurs in about one in ten pregnancies. Experiments by the research team showed
that adding extracts of garlic to cells from the placenta of women likely to
suffer from these conditions was able to quickly stimulate growth. Furthermore,
the activity of key enzemes that are reduced in the abnormal pregnancies were
significantly increased when garlic was added.
Several beneficial effects are ascribed to Allium sativum (garlic), for example, lowering of the arterial blood pressure as well as an inhibition of arteriosclerotic vascular changes.
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Diaphoretic, diuretic, expectorant, stimulant. Many marvellous effects and healing powers have been ascribed to Garlic. It possesses stimulant and stomachic properties in addition to its other virtues.
As an antiseptic, its use has long been recognized. In the late war it was widely employed in the control of suppuration in wounds. The raw juice is expressed, diluted with water, and put on swabs of sterilized Sphagnum moss, which are applied to the wound. Where this treatment has been given, it has been proved that there have been no septic results, and the lives of thousands of men have been saved by its use.
It is sometimes externally applied in ointments and lotions, and as an antiseptic, to disperse hard swellings, also pounded and employed as a poultice for scrofulous sores. It is said to prevent anthrax in cattle, being largely used for the purpose.
In olden days, Garlic was employed as a specific for leprosy. It was also believed that it had most beneficial results in cases of smallpox, if cut small and applied to the soles of the feet in a linen cloth, renewed daily.
Garlic has also been widely studied for its role in cardiovascular health. Dioscorides was a well-known first century physician who wrote that garlic "clears the arteries and opens the mouths of veins." Recent studies have examined its effect on blood cholesterol with mixed results. Some studies have shown a reduction in LDL cholesterol, or bad cholesterol levels, while others have not. However, if garlic does indeed have cardio-protective properties, it may be traced--at least in part--to its proposed ability to reduce the formation of blood clots, a claim that is gaining research attention of its own.
As if this were not enough to get garlic into the medicinal plant hall-of-fame, garlic has also been studied for its immune boosting properties. Numerous studies performed in recent years indicate that the compound allicin, found in fresh garlic, has antibiotic and antifungal properties.