Published on November 15, 2016

Benefits from our local bogsBenefits from our local bogs

Those cranberries you serve with turkey this Thanksgiving pack more than just a refreshing tart contrast to the rich meat. They are also nutritional powerhouses that may help prevent cancer, urinary tract infections, stomach ulcers, gum disease and cardiovascular disease.

Like other brightly colored fruits and vegetables, cranberries are rich in cancer-fighting antioxidants and polyphenols, said nutritionist and registered dietitian Amy Rose Sager of Sandwich, who works for the Visiting Nurse Association of Cape Cod. Antioxidants neutralize free radicals, highly reactive particles that damage cells and DNA and may contribute to cancer and other diseases, according to the National Cancer Institute. Polyphenols, including flavonoids, are a group of antioxidants produced in plants, and have been found to help prevent cancer and heart disease, according to an article in the journal Oxidative Medicine and Cellular Longevity.

“The problem we have is that they’re hard to eat by themselves,” said Sager, who also runs Leap Into Wellness, a health counseling business focused on a plant-based diet.

To counter the piquant taste of pure juice, cranberry drinks often are made with sugar or high-fructose corn syrup. Sager recommends skipping the sugar and eating the whole fruit to get the most benefit.

“Sometimes we don’t think of them year-round, but you can buy them now and freeze them,” she said. “You can  freeze them and throw a few in the blender for a smoothie.”

As a dietary supplement, cranberry products are used most commonly to help prevent urinary tract infections. It was initially thought that cranberries acidified urine, making it inhospitable to bacteria. But it was later determined that a substance in cranberries, known as A-type proathocyanidins, likely inhibit the ability Escherichia coli (E. coli) to adhere to the urinary tract wall. This bacterium causes most urinary tract infections.

Cranberries can be effective in preventing urinary tract infections, but not as a treatment once someone has an infection, according to Sager.

Evidence Is Mixed on UTI Prevention

The evidence is mixed as to whether cranberries help prevent UTIs, according to the National Center for Complementary and Integrative Health of the National Institutes of Health, which cited two large research reviews both done in 2012. However, a 24-week Boston University study performed earlier this year of 373 women conducted at 17 sites in the United States and one in France indicated that patients prone to recurrent infections could significantly reduce the number of infections by consuming 100 percent cranberry juice. The study, published in the American Journal of Clinical Nutrition, found participants developed 39 urinary tract infections over the study, in comparison with 67 cases in the placebo group.

The same mechanism that prevents E. coli from attaching in the urinary tract may also prevent Helicobacter pylori (H. pylori) bacteria from attaching to the stomach wall, where it can cause ulcers and gastric cancer, but more research is needed to confirm this, according to the University of Maryland Medical Center. H. pylori also is implicated in plaque and gum disease, so cranberries may be useful in preventing those dental problems, too.

The tart little berries might even help your heart. A June U.S. News & World Report article says cranberries’ flavonoids reduce inflammation, increase levels of good cholesterol (high-density lipoproteins or HDLs) and help lower blood pressure by relaxing blood vessels.

Too much of even a good thing can be bad for you. In addition to the high sugar content of some preparations, cranberries increase the time that the blood thinner warfarin (sold as Coumadin) stays in the body. Therefore consumption may be contraindicated, according to the University of Maryland Medical Center, which notes that the berries contain salicylic acid. Aspirin, another blood thinner, breaks down into salicylic acid in the body. The Mayo Clinic suggests restricting cranberry consumption if taking blood thinners and medications that affect the liver.

One other caveat: Cranberry juice, like apple juice, contains oxalates, and can contribute to formation of calcium oxalate kidney stones, according to Renal and Urology News, so people prone to them should avoid overconsumption.

The nutritional content of cranberry drinks, supplements and foods varies, and some may not even include the skins where most of the antioxidants reside. To help consumers, the Cape Cod Cranberry Growers Association offers these guidelines to get the same amount of “bacteria-blocking health benefits” from different forms of cranberry products:

  • 10 ounces of cranberry cocktail
  • 5 cups of fresh or frozen cranberries
  • 1 ounce sweetened cranberries
  • ½ cup of cranberry sauce

Speaking of sauce, nutritionist Sager recommended this recipe from Forks Over Knives for an uncooked cranberry sauce made without added sugar – it relies on dates for sweetness.

  • 1 12-ounce bag of cranberries
  • Zest and fruit of two oranges
  • 1 cup of pitted dates
  • 2 tablespoons of psyllium husk (optional)

Blend all the ingredients in a food processor using an S-shaped blade until desired consistency is reached.

[Featured Image via Cape Cod Cranberry Growers’ Association Facebook Page.]