When it’s autumn in North America, you can bet it’s time for cranberry season. As the days grow shorter and the leaves begin to turn, people begin looking forward to all things cranberry, from cranberry sauce to muffins, stuffing, cakes, and pies. And unlike many of the unhealthy choices we indulge in each fall, cranberries not only taste good, but they’re also good for us. So come with us as we explore cranberries health benefits. By the end, you’ll fall in love with this healthy fall fruit…if you haven’t already!
Cranberry Nutrition Facts
When it comes to cranberries, the most popular variety is the American cranberry, or Vaccinium macrocarpon. A relative of blueberries, the American cranberry is native to Canada and the United States and grows best in cool, wet, acidic conditions.
While most plants would turn their roots up at this kind of environment, the rather harsh growing conditions of the cranberry make for a fruit that’s rich in vitamin C, vitamin K, vitamin E, manganese, and dietary fiber. In fact, just 1 cup of cranberries contains 20% of the recommended dietary allowance of fiber.
Cranberries are also rich in phytochemicals—biologically active compounds that protect plants and give them their characteristic taste, color, and smell. While there are thousands of known phytochemicals, cranberries happen to be particularly good sources of phytonutrients called polyphenols.
Like Russian nesting dolls, polyphenols can be further broken down into flavonoids, phenolic acids, and non-flavonoid polyphenols. Of these, cranberries are especially rich in flavonoids—including quercetin, myricetin, and the anthocyanins peonidin and A-type proanthocyanidins—and a terpene called ursolic acid.
Over the past several decades, researchers have become increasingly interested in phytochemicals like the ones found in cranberries and have discovered that they act not only as antioxidants and anti-inflammatories but also as antimicrobial and anti-cancer agents.
As you might imagine, these properties contribute to an impressive array of health benefits. For example, phytochemicals are known to reduce oxidative stress and inflammation, boost the immune system, lower blood pressure and cholesterol levels, aid in the prevention of chronic diseases like heart disease and diabetes, and kill bacteria, viruses, fungi, and even cancer cells.
The antioxidant properties of cranberries, in particular, may even make them useful as a natural alternative to synthetic preservatives used in meat preservation, as was found in a study of cranberry extract published in the journal Food Research International.
Cranberries Health Benefits
While most of us probably won’t be preserving our own meat any time soon, the health benefits of cranberries are something we can all take part in. And studies have shown that these benefits are ripe for the taking regardless of whether cranberry juice, dried cranberries, or cranberry extracts are used.
As mentioned, many of the phytochemicals in cranberries exhibit significant antimicrobial properties. And a study published in the journal Food Science and Technology International found that cranberry juice displays potent antibacterial effects against Staphylococcus aureus. The results achieved were even greater than those seen with both acai berries and blueberries.
Cranberries are perhaps best known for their ability to prevent and treat urinary tract infections (UTIs). This is due to their high levels of proanthocyanidins, which have been found to inhibit the adherence of Escherichia coli in the urinary tract. In fact, several studies, including a 2006 study published in the World Journal of Urology, have found that cranberries significantly reduce the adherence of various strains of E. coli known to cause UTIs.
Cranberries have also been found to protect gut health by exerting an antibacterial effect against Helicobacter pylori—the main cause of peptic ulcers. A study in the journal Helicobacter found that the risk of both gastric ulcers and gastric cancer can be reduced by regular consumption of cranberry juice.
Finally, a study published in Material Science and Engineering found that a gel composed of cranberry juice concentrate was as effective as chlorhexidine—a widely used antimicrobial—against a wide array of bacteria known to cause gum disease.
Multiple studies have found that the antithrombotic and anti-inflammatory effects of the polyphenols in cranberries reduce many of the risk factors associated with cardiovascular disease.
Some of the benefits seen with consumption of cranberries include lower blood pressure, decreased aggregation of platelets, and reduced levels of oxidized LDL—a particularly harmful type of cholesterol that forms when LDL interacts with free radicals. Oxidized LDL is associated with a higher risk of blood vessel plaque, which in turn puts a person at greater risk of heart attacks and strokes.
In addition, a recent clinical trial published in the European Journal of Nutrition found that daily consumption of low-calorie cranberry juice over a period of 8 weeks supported heart health by improving blood sugar control and increasing levels of HDL cholesterol.
Of the phytochemicals in cranberries that are known to have a beneficial effect on blood sugar, multiple studies have shown that anthocyanins, in particular, may be among the most significant.
These important polyphenols have been found to aid in the prevention of type 2 diabetes by regulating carbohydrate metabolism, reducing levels of inflammation, improving insulin secretion, and decreasing insulin resistance—a precursor to diabetes that’s marked by a reduced ability of the body’s cells to absorb insulin.
For example, a study published in the Journal of Research in Medical Sciences found that male diabetics who drank a cup of cranberry juice daily for 12 weeks experienced a significant decrease in both blood sugar and markers associated with an increased risk of heart disease.
Like the clinical trial mentioned in the previous section, the results of this study showcase the interconnectedness of diabetes and heart disease and the preventive effect cranberries may have on both.
Cancer Prevention and Treatment
The powerful phytonutrients in cranberries may also have a part to play in the prevention and treatment of cancer via their antioxidant properties as well as their ability to induce cancer cell death, reduce the proliferation of cancer cells, and alter the various signaling pathways associated with tumor growth.
In fact, a meta-analysis published in the journal Antioxidants documented strong evidence showing that cranberries are effective against an astounding 17 different types of cancer, including esophageal, stomach, colon, bladder, prostate, and breast cancers as well as lymphoma and glioblastoma—a malignant form of brain cancer that’s notoriously difficult to treat.
Do Cranberries Cause Kidney Stones?
While some sources warn that the high concentration of oxalates in cranberries may lead to a higher risk of kidney stones, some studies have found that consumption of cranberries actually decreases the formation of stones.
For example, a clinical trial published in BJU International found that participants who drank cranberry juice diluted with water every day for 2 weeks experienced a significant decrease in factors that contribute to kidney stone development and an increase in factors that protect against the development of stones.
As you can see, it appears that any way you look at it, cranberries are a great addition to a healthy diet. So whether you prefer whole cranberries for homemade cranberry sauce or bread, cranberry juice, or dried cranberries for cereal and snacking, it’s never a bad idea to crank up your cranberry consumption!