used for hypertension, hyperlipidemia, coronary heart disease, age-related vascular
changes and atherosclerosis, myocardial infarction, earaches, chronic fatigue
syndrome, and menstrual disorders. Garlic is also used to treat Helicobacter
pylori infection. Other uses include treatment of allergic rhinitis, traveller's
diarrhoea, colds, and flu. It is also used for immune system stimulation, and
prevention and treatment of bacterial and fungal infections. Other uses include
treatment of fever, coughs, headache, stomachache,sinus congestion, athlete's
foot, gout, rheumatism, bronchitis, low blood pressure. It is also used as an
aphrodisiac, for enhancing circulation, fighting stress and fatigue.
garlic oil is used for fungal infections.
garlic is used alone or in combination with yogurt for vaginitis.
and beverages, fresh garlic, garlic powder, and garlic oil are used as flavour
concerns regarding safety when used orally and appropriately. Garlic has been
used safely in clinical studies lasting up to 7 years without reports of
Likely to be safe when used orally and appropriately, short-term. In one study,
garlic extract 300 mg three times daily had side effects comparable to placebo
when used in children ages 8-18 years for eight weeks.77 There are no case reports available of significant
adverse events or mortality in children associated with ingestion of garlic.
and Lactation: No concerns regarding safety when used orally in amounts
commonly found in foods.78
Taking low doses of garlic powder orally, 300 mg per day, seems to lessen
age-related decreases in aortic elasticity.
doses of 900 mg per day seem to slow development of atherosclerosis in both
arteries when used over a four-year period.79,72,73
cancer. Several population studies suggest that increased dietary garlic
consumption can decrease risk of developing colorectal cancer.84,80,81,82 However, garlic supplements do
not seem to offer this benefit.83
cancer. Some evidence from population studies suggests that increasing dietary
garlic consumption is associated with a decreased risk of developing stomach
Blood Pressure. Some clinical research shows that taking garlic orally can
modestly reduce blood pressure in patients with hypertension and in people with
normal blood pressure.87,88,89,63,75,90
analysis, garlic reduced systolic blood pressure by about 8% and diastolic
blood pressure by about 7%, compared to placebo in patients with hypertension.90
Applying a garlic gel containing 0.6% ajoene seems to be as effective as
terbinafine 1% cream.91
pedis (athlete's foot). Applying a garlic gel containing 1% ajoene seems to be
more effective than 0.6% ajoene gel, and seems to beas effective as 1% terbinafine
(Lamisil) for tinea pedis infections. Sixty days after completing one week of
treatment 1% ajoene produces 100% mycologic cure, 0.6 % produces 72% mycologic
cure, and 1% terbinafine produces 94% mycologic cure.92,93
SCIENTIFIC EVIDENCE to RATE
cold. Preliminary clinical research suggests garlic might reduce the frequency
and number of colds when taken prophylactically.94
applicable part of garlic is the bulb. Garlic is mostly used for its antihyperlipidemic,
antihypertensive, and antifungal effects. However, it is also reported to have
antibacterial, antiparasite (worms), antiviral, antispasmodic, promotes
sweating, expectorant, immunostimulant, and antithrombotic effects.95,96,97,98,99 Many of the pharmacological
effects of garlic are attributed to the allicin, ajoene, and other organosulfur
constituents such as S-allyl-L-cysteine.98
that the effectiveness of garlic products might to be determined by their
ability to yield allicin, which in turn triggers production of other active constituents.100
garlic cells in fresh garlic contain the odorless amino acid, alliin. When
intact cells are broken, alliin comes intocontact with the enzyme alliinase in
garlic, producing allicin, an unstable, odiferous compound.100,97 Fresh garlic contains approximately
1% alliin. One milligram of alliin is converted to 0.458mg allicin.101 Further conversion yields ajoene. The amount of
allicin in garlic preparations is dependent upon the method of preparation.
Processes that involve maceration of the garlic clove increase the activity of
allicinase. Freeze-dried garlic may contain little or no allicin. To improve
effectiveness, garlic preparations may be coated to protect the active constituents
stomach acid.102 Heat and steam distillation used
to produce garlic oil from crushed garlic converts allicin to allyl sulfides
which are also thought to have biological activity.100
aged to reduce the content of other sulfur compounds and the odor commonly
associated with garlic. The process to produce odorless aged garlic extract
reduces the alliin content to only 3% of what is typically contained in fresh garlic.101
garlic extract is usually standardized to S-allyl-L-cysteine, another major
organosulfur constituent in garlic.95
patients with hyperlipidemia, garlic might lower cholesterol levels by acting
as a HMG-CoA reductase inhibitor (statin).103,104 There is some evidence the constituent
S-allyl-L-cysteine may be a potent inhibitor of hepatic cholesterol synthesis.105
For age-related vascular changes and atherosclerosis, garlic is thought
to be beneficial and protect vascular endothelial cells from injury by reducing
oxidative stress, inhibiting low-density lipoprotein (LDL) oxidation, and
through antithrombotic effects.106,107,98,108 There is evidence that LDL oxidation may be inhibited
by the constituents S-allyl cysteine, S-allyl mercaptocysteine, alliin, allixin,
and by N-acetyl-S-allyl cysteine, a metabolite of S-allyl cysteine.108 Garlic appears
to prevent endothelial cell depletion of glutathione, which may be responsible
for its antioxidant effects.106
powder and aged garlic preparations have been shown to have antiplatelet properties
in both patients with cardiovascular disease and in healthy volunteers.109,95,96,110,111
has been found to have antithrombotic properties and can increase fibrinolytic
activity,decrease platelet aggregation and adhesion, increase the prothrombin
time (PT), and inhibit metabolic enzymes in platelets responsible for the
conversion of arachidonic acid into prostaglandins and other products.95,96,98,112 Raw garlic seems to have more
potent antiplatelet properties
cooked garlic.113,114,115 Crushing garlic before cooking
might prevent some of the loss of antiplatelet activity.115 Garlic oil does not appear to affect platelet aggregation.116
thought to reduce blood pressure by causing smooth muscle relaxation and
vasodilation by activating production of endothelium-derived relaxation factor (EDRF,
also seems to have humoral and cellular immunostimulant activity.
constituents allicin and ajoene are thought to beresponsible for garlic's
antifungal activity against ringworm infections.98,93 Fresh garlic, but not aged garlic, has shown
activity against Escherichia coli, methicillin-resistant Staph aureus,
salmonella enteritidis, and Candida albicans in the laboratory; it has been
suggested as a food additive to prevent food poisoning.
118 Preliminary evidence suggests
that garlic compounds might have activity against viruses
garlic has dose-relatedadverse effects, which most commonly include breath and
body odour, mouth and gastrointestinal burning or irritation, heartburn, flatulence,
nausea, vomiting, and diarrhoea. These effects can be more pronounced with
consumption of raw garlic or in patients unaccustomed to eating garlic.78,65,101 Oral use of garlic can also cause
changes to the intestinalflora,78 ,101 which
might result in gastrointestinal upset. Garlic's effect on platelet function is
well known, and can possibly increase the risk of bleeding.
Interactions with Herbs & Supplements:
Herbs and Supplements: Concomitant use of herbs that have constituents that
might affect platelet aggregation could theoretically increase the risk of
bleeding in some people. These herbs include angelica, clove, danshen, ginger,
ginkgo, red clover, turmeric, vitamin E, willow, and others.109,95,96,110,111
Interactions with Drugs:
Drugs including Warfarin.
Interactions with Foods:
Interactions with Lab Tests:
Pressure: Garlic can lower blood pressure and blood pressure readings.87,88,89
Garlic can lower serum cholesterol concentrations and test results.87,88,89
Interactions with Diseases or Conditions:
(GI) Irritation: Garlic can irritate the GI tract; dose related, resolves on
discontinue one to two weeks prior to scheduled surgery.121,101,122
Clare’s Blends: 1gm/day
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