As one of only three commercially cultivated fruits native to North America, the cranberry was a versatile staple in Native American life prior to its arrival on the Thanksgiving table. In addition to using cranberries as a food preservative and fabric dye, many tribes believed cranberries were healing agents that could draw poison from arrow wounds and calm the nerves.
Packed with vitamin C, cranberries have an acidic property that was once thought to relieve urinary tract infections by acidifying the urine and creating an environment inhospitable to bacteria. Scientists now know that cranberries contain proanthocyanidins (PACs), which prevent the adhesion of bacteria to the urinary tract wall. These compounds can actually change the shape of disease-causing bacterium, making it impossible for them to bind to human cells and amass into an infection.
Only the PACs in cranberries and their close relatives — blueberries — have this anti-adhesion effect. Research shows that the cranberry’s anti-adhesion properties are not limited to the urinary tract; they may also inhibit the bacteria associated with stomach ulcers, acid reflux and gastritis, as well as kidney and bladder infections. Plus, PACs can fight a broad range of bacteria, including Staphylococcus, salmonella and E. coli, reducing the need for antibiotics.
Another cranberry component called NDM has been shown to inhibit and even reverse certain oral bacteria responsible for plaque and periodontal disease. In fact, the tart fruit is believed to be so effective in preventing cavities and gum disease that a cranberry mouthwash may not be too far away.
Beyond bacteria, cranberries may also provide protection from viruses. A Taiwanese study demonstrated that cranberry consumption helps to fight against the herpes simplex-2 virus, which can cause genital sores or ulcers, and inflammation of the brain. In other studies, cranberries mitigated the development of intestinal viruses.
The crimson berry is packed with antioxidants: It contains more phenols on a fresh weight basis than 20 other common fruits and vegetables such as red grapes, spinach and strawberries. These phytochemicals serve as a defense against atherosclerosis and related cardiovascular diseases including blood clotting and heart attacks. Additionally, they may stem tumor growth in breast, lung, lymph, stomach and other cancers.
Could the fountain of youth flow with cranberry juice? There is mounting evidence that cranberries can help protect the brain from neurological damage and the effects of aging. In one study at Virginia Polytechnic Institute and State University, cranberry consumption improved participants’ memories. The findings indicate that cranberries may be essential to maintaining a healthy mind as well as a healthy body.
So how much of the good stuff should you be consuming? The National Kidney Foundation recommends drinking a 10-ounce glass of cranberry juice daily to prevent urinary tract infections. Yet for round-the-clock anti-adhesion benefits, some doctors say that two well-spaced servings a day may be better than one.
Whether you choose dried or fresh cranberries, juice blends, jarred or canned sauces, or baked into pastries and breads, you can reap the health rewards. Still, it’s wise to consume moderately and avoid preparations that sweeten the berries with excessive sugar and artificial flavorings, which can raise blood sugar levels. You don’t want to trade one poison arrow for another.