Garlic is known to have been
used for 7,000 years in cooking and as a medicine. It is one of the first plants cultivated by humans. Garlic has a long history of medicinal
uses – including its use by grave diggers during the terrible episodes of bubonic
plague in the 14th and 15th centuries that killed half of
human populations in areas where it struck. Grave diggers
drank wine with crushed garlic to prevent catching the plague – perhaps their
skin odor repelled the fleas that transmitted plague from infected rats. Perhaps this was hype, and hope. However, there are numerous current
studies on the medicinal properties of garlic that are promising,
Garlic as an antioxidant: Studies from the National Research Council of
Canada have shown that allicin, which gives garlic its aroma and flavor, acts
as an extremely powerful antioxidant. Garlic does not have a substantial amount of the compounds
responsible for antioxidant activity in green tea or grapes. The researchers found that a
decomposition product of allicin, called sulfenic acid, acts rapidly when in
contact with free radicals. The
author wrote ‘The reaction between the sulfenic acid and radicals is as fast as
it can get, limited only by the time it takes for the two molecules to come in
contact. No one has ever seen
compounds, natural or synthetic, react this quickly as antioxidants.’ While onions, leeks and shallots have a
compound similar to allicin, they do not have the same medicinal properties,
due to a slower rate of decomposition of allicin.
Cystic Fibrosis: this is an inherited lung disease that causes lung infections
and limits the ability to breath. It is usually diagnosed in childhood and may
be fatal. A group of infectious bacteria in cystic fibrosis are resistant to
most antibiotics. The chemical
known as allicin produced by garlic bulbs may be helpful in the future to kill
resistant bacteria. Research is being
done at the University of Edinburgh’s School of Chemistry. Research on garlic’s antibiotic actions
is also going on at the University of Copenhagen and many other centers. More
effective antibiotics are desperately needed.
Brain protection:
Researchers at the University of Missouri have found a nutrient in
garlic that protects brain cells against the kind of cell damage that
promotes cognitive problems,
Parkinson’s disease and stroke.
This garlic nutrient, which they call FruArg,, promotes the production of antioxidants which offer
protective and healing benefits to brain cells, Research is ongoing.
Reduction of “soft plaque” in arteries: Research at UCLA Medical Center has shown that patients at risk of
heart attack benefited from using aged garlic extract. ‘Soft plaque’ in the linings of
arteries is composed mainly of white blood cells, which when released promote
blood clotting. Researchers
studied 55 patients who had been diagnosed with ‘metabolic syndrome’ (obesity,
high blood pressure, and other cardiac risk factors). After a workup that
measured the plaque in their coronary arteries, they were given either a
placebo or a dose of 2,400 mg of Aged Garlic Extract daily. A year later those who had taken the
garlic extract showed slowed total plaque accumulation by 80%.
Cancer protection: Several population studies show an association between increased intake of garlic and
reduced risk of certain cancers, including cancers of the stomach, colon, esophagus, pancreas, and breast. An analysis of data from seven population studies showed that the higher
the amount of raw and cooked garlic consumed, the lower the risk of stomach and
colorectal cancer. These studies are
from Europe, the U.S. and China.
Chinese studies also show a decreased risk of prostate cancer with
greater intake of garlic and scallions.
Garlic as a ‘blood
thinner’: Garlic has an anticoagulant effect. Many doctors advise stopping high doses
of garlic 10 days before surgery.
If you are on an anticoagulant medicine, discuss this with your
doctor. Usual doses of garlic in cooking should not be a problem.
There is a restaurant in
San Francisco called The Stinking Rose, which features garlic in every
course. If any reader wants to organize
a trip there, count me in!
Sadja Greenwood MD, MPH past issues on this blog
