Garlic may be the best weapon against a type of bacteria responsible for millions of cases of food poisoning in the United States every year, according to a new study. Researchers from Washington State University discovered that a compound found in garlic was 100 times more effective than antibiotics at killing Campylobacter, most common cause of food-borne bacterial illness in the United States.
The compound, diallyl sulphide, which is responsible for the garlic smell that sticks to your hands when you cook, worked better and faster than the common antibiotic treatments for Campylobacter, erythromycin and ciprofloxacin.
Eating massive quantities of garlic may not help if you are already sick, but diallyl sulphide "has the potential to reduce disease-causing bacteria in the environment and in our food supply," Xiaonan Lu, coauthor of the study, published Tuesday in the Journal of Antimicrobial Chemotherapy, and a postdoctoral researcher at Washington State University, said in a statement.
"Diallyl sulfide could make many foods safer to eat," Barbara Rasco, study co-author and professor of food science at Washington State University, said in a statement. "It can be used to clean food preparation surfaces and as a preservative in packaged foods like potato and pasta salads, coleslaw and deli meats. This would not only extend shelf life but it would also reduce the growth of potentially bad bacteria."
More than 2 million Americans are affected by Campylobacter ever year, according to the Centers for Disease Control and Prevention. The majority of the infections come from eating raw or undercooked poultry or from eating foods that have been cross contaminated via a surface or utensil that was used to prepare poultry.
Symptoms of Campylobacter infection include diarrhea, cramping, fever and abdominal pain. The bacteria are also responsible for triggering almost a third of Guillain-Barré syndrome cases, a rare, paralyzing condition, researchers said.
The bacteria are surrounded by a biofilm -- a slimy protective surface that makes them 1000 times harder to kill than traditional bacteria, according to the study. The biofilm also sticks to food and other surfaces, which helps it spread.
In the research trials, Diallyl sulphide penetrated the biofilm and killed the bacteria in a fraction of the time it took the antibiotics and killed more of the bacteria than the antibiotics as well.
This latest study adds to the mounting evidence of garlic's benefits. Previous studies have shown that garlic can protect against cardiovascular disease and cancer.
"Studies suggest that garlic consumption may reduce the risk of developing several types of cancer, especially cancers of the gastrointestinal tract," the National Cancer Institute says on its website. "Evidence also suggests that increased garlic consumption may reduce pancreatic cancer risk. A study conducted in the San Francisco Bay area found that pancreatic cancer risk was 54 percent lower in people who ate larger amounts of garlic compared with those who ate lower amounts."
However, people should not rush out and buy mass quantities of garlic, the NCI warned. The amount needed to reduce disease risk is unknown and too much consumption cause excess bleeding, asthma and stomach and digestion problems.
"The National Cancer Institute does not recommend any dietary supplement for the prevention of cancer, but recognizes garlic as one of several vegetables with potential anticancer properties," the organization says on its website. "Because all garlic preparations are not the same, it is difficult to determine the exact amount of garlic that may be needed to reduce cancer risk. Furthermore, the active compounds present in garlic may lose their effectiveness with time, handling, and processing."
The history of using garlic to fight disease goes back several thousand years, Lu, who has published three studies on garlic's health benefits, said in a 2011 statement. Though our ancestors knew garlic helped keep people healthy, they were not aware of why, leading many to believe it had mystical properties, This probably explains why people though garlic could ward off vampires, Lu said.
"In ancient society people used garlic to cure diseases," he said. "However, they did not know why it worked. Now we are finding out."
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