April 29, 2008, Updated July 2, 2014

Cranberries have long been known as a popular folk remedy for the treatment of urinary tract infections, but until recently there was no scientific evidence to back up this claim. Now Professor Itzhak Ofek of Tel Aviv University has discovered that the benefits ascribed to cranberries are not only real – there are several more as well.

“Cranberries started as a folk medicine in the US,” Ofek told ISRAEL21c. “Every fourth American in the ’60s knew it was good for urinary tract infection.” Ofek’s goal was to find out the truth behind the myth.

With his research funded by the cranberry juice-producing monolith Ocean Spray, Ofek recently published his findings in the journal Molecular Nutrition & Food Research. There is only one snag: the benefits of cranberries, though prodigious, appear to apply only to women.

“It appears that in certain infections, such as ulcers caused by H. pylori bacteria, a clinical trial showed that the cranberry has beneficial effects for women only,” says Ofek. “In urinary tract infections (UTI), the cranberry has been tested only on women and has proven to be beneficial, although UTI is primarily an infectious disease most common in women.”

Ofek has been researching the healing properties of the cranberry for more than a decade, and has discovered numerous benefits in the course of his research. He began at the logical starting point: the claim that cranberries prevent urinary tract infections. Ofek explains that while other researchers had investigated this phenomenon in the past, they had been looking for an antibiotic substance in cranberries.

“We thought: perhaps they did the wrong test?” says Ofek. Sure enough, he and his colleagues found the answer when they tested cranberries for an anti-bacterial substance.

He discovered that cranberries contain a heavy molecule, also known as non-dialyzable material or NDM. This molecule, isolated by Ofek and collaborator Professor Nathan Sharon of the Weizmann Institute, seems to coat some bodily surfaces with Teflon-like efficiency, preventing infection-causing agents from taking root. Surprisingly, the NDM has no effect on good bacteria.

More recently in collaboration with other researchers, Ofek discovered that the NDM substance inhibits the flu virus from attaching to cells. This NDM also has a gastrointestinal benefit: it inhibits unhealthy bacteria from attaching to gastric cells, thereby preventing ulcers.

But cranberries don’t have to be swallowed to provide benefits. When Ofek explored other properties of the cranberry in collaboration with Professor Ervin Weiss of Hadassah Medical Center, they discovered that the benefits of cranberries extend to the teeth as well; a property of cranberries is that it can reduce the bacteria in the mouth that causes cavities. This find could end up giving current brands of mouthwash a run for their money.

However, Ofek cautions against gargling with cranberry juice. “The cranberry is very tart and acidic, so dentists say it will hurt your teeth. That’s why we’re isolating the substance that helps, to put in mouthwash.”

This substance has been patented by Ramot, TAU’s technology transfer company, and is currently the subject of negotiations with companies and investors.

Ramot is also commercializing this active substance in pill form, for people who don’t like to drink cranberry juice but want to reap the benefits.

Ofek’s work isn’t done: he’s still investigating the cranberry for further health benefits, and to see if it can also help men. While he acknowledges that other fruits may also contain healing properties that are waiting to be explored, Ofek also says that in comparison to other fruits, “Cranberries are unique.” And since his research was publicized, cranberry juice consumption has gone up. “The sales of cranberry juice were tripled since our study,” says Ofek.

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Jason Harris

Jason Harris

Executive Director

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