Give Thanks: Cranberries, Best of Super Foods

By LEE DYE

Nov. 21, 2007

Here's something to be thankful for. Amid the potentially deadly turkey dressing, gravy and pie on your Thanksgiving Day table, there will likely be one of the healthiest foods on the planet. In fact, if it were just discovered today, it would probably be ranked among the top medical discoveries of the year, if not the decade.

We're talking cranberries here, those unpretentious red berries that scientists have been saying for years are nearly miraculous in terms of what they can do for our health. And now they are coming up with a better understanding of just how cranberries accomplish their magic.

But first, here's the lowdown:

The cranberry is the No. 1 antioxidant, containing the highest concentration of phenols, a type of antioxidant that is thought to reduce the risk of chronic diseases such as cancer, stroke and heart disease (University of Scranton).

Cranberries contain a compound that helps prevent metastasis, the spread of cancer to other parts of the body (University of Massachusetts-Dartmouth). Cranberries may also improve chemotherapy for ovarian cancer (Rutgers University).

Cranberry juice, long recognized for its ability to lessen urinary tract infections, also works against a number of gastrointestinal viruses (St. Francis College).

The cranberry has several antioxidants (flavonoids) that fight off the bacterium that causes tooth decay (University of Rochester School of Medicine and Dentistry).

And there is considerable evidence that cranberries can reduce the damage from stroke (University of Massachusetts-Dartmouth); improve the health of the heart, at least in pigs (University of Wisconsin-Madison); and work like antibiotics on E. coli, a class of microorganisms responsible for human illnesses ranging from kidney infections to gastroenteritis (Worcester Polytechnic Institute).

Phew. That's a lot, especially for a small berry that is almost lost in the avalanche of food that spills over the American dinner table each November. But how, one might ask, does it do all that?

Scientists at the Worcester Polytechnic Institute in Worcester, Mass., have been hammering away at that for years, and they have come up with an explanation for how cranberries ward off urinary tract infections.

Researchers have long suspected that the berries must do something to stop harmful bacteria from latching on to the lining of the urinary tract.

Terri Camesano, associate professor of chemical engineering at WPI, heads a team of researchers who have found that cranberry juice causes chemical changes in the bacteria. Those changes work in several ways to create a barrier that keeps the bacteria from even getting close to the lining. For example, cranberry juice causes tiny tendrils on the surface of E. coli to become compressed, reducing the bacteria's ability to latch on to the lining.

If the bacteria can't attach to the sides of the tract, it can't do its damage. The research suggests that the juice is extremely powerful, even in very diluted stages. Only a 5 percent solution is required to reduce the bacteria's ability to latch on to the urinary tract.