Garlic vs. 'Superbug'

Garlic vs. 'superbug'

Ancient medicinal food contains ingredient shown to fight MRSA

By Julie Deardorff | Tribune health and fitness writer

Drug companies are testing more than a dozen new medicines and vaccines to treat "hospital superbugs," or drug-resistant staph bacteria, but an ancient medicinal food might be just what the doctor should order.

Garlic, well known for its natural antibiotic properties, contains an ingredient that has been shown to effectively kill methicillin-resistant Staphylococcus aureus (MRSA), a virulent microbe that wreaks havoc in skin and soft-tissue wounds, several studies have shown.

The nasty superbacterium that now defies most drug treatments infected more than 90,000 Americans last year and killed 19,000, making it a significant public health problem, a new federal report says. Though 85 percent of the staph infections were in hospitals or other healthcare facilities, MRSA also is marching into schools, health clubs and other crowded places.

'One of the solutions'

Garlic, which was mentioned 2,000 years ago in Chinese medical literature and also used by Aristotle and Hippocrates, is "one of the solutions," said Ron Cutler, a microbiologist at the University of East London. Cutler published research in 2004 showing that a compound created in the plant, allicin, kills several different strains of MRSA.

Garlic bulbs contain hundreds of components, including allicin, an amino acid byproduct that is released when raw garlic is crushed or cut. The creation of allicin, a self-defense mechanism in the plants, is what makes garlic so pungent; it?s also the secret behind garlic's healing and medicinal properties.

In addition to reducing the clotting tendency of platelets, garlic can be used as an antiseptic and antibacterial because it stops micro-organisms such as bacteria from reproducing. Studies show that in large doses, garlic can reduce blood pressure and overactivity of the intestine, and it can slightly lower blood-sugar levels. And unlike modern antibiotics, the body does not seem to build up a resistance to garlic, researchers say.

"We believe garlic is effective against MRSA and other resistant bugs," said Mehmet Oz, medical director of the Integrated Medicine Center at New York-Presbyterian/Columbia University and director of the Heart Institute. "[Allicin] is a fascinating mechanism that plants use to protect themselves."

One proposed theory is that allicin blocks certain "enzymes found in pathogenic bacteria, thus crippling the bacteria from invading healthy tissue," said registered dietitian Dave Grotto, author of "101 Foods That Could Save Your Life!" (Bantam Books, $14), which will be released next month. "Another mechanism is that garlic has the ability to prevent the reading of genetic material so the end result is that MRSA cells can?t replicate."

Still, while garlic appears promising, others say more studies using real patients are needed before it can be declared a breakthrough.

"We have many agents that are effective against bacteria in the test tube or that can be used as disinfectants/antiseptics outside of the body," said pharmacist Frank Tverdek, in the infectious-diseases section at Rush University Medical Center. "However, using it in the human body as a treatment for an infection is a whole different matter.

"In order for the compound to be effective, it must be able to be administered in adequate dosage, distributed to the site of the infection in the body, exhibit sustained activity against the MRSA organism and all the while remain a safe intervention," Tverdek said.

One problem is that natural extracts of allicin can be unstable. So researchers, including Cutler, are working to develop so-called stabilized allicin products, including spraying liquids, creams and oral capsules.

Processing the key

Garlic's effectiveness also is affected by the way it's processed. Cooking can destroy some of the active compounds, microwaving appears to completely ruin them and preparations formulated to be odorless might be inactive.

"Allicin is only found in fresh, raw garlic and degrades rapidly once it's produced, so the usefulness of crushing garlic bulbs and rubbing it on the body is probably very limited," said Mary Beth Minyard, associate project leader in bacteriology at Southern Research Institute in Birmingham, Ala.

Still, garlic has plenty of proven healing benefits and few side effects, aside from an offputting aroma. (It also may interact with blood thinners and burn your throat and stomach if you eat too much of it.)

"I think it is quite plausible for consumers to arm themselves with an arsenal of bacteriafighting foods [such as garlic] as a protective measure, not in lieu of medicine, but [as] a prophylactic measure," Grotto said.

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