By Dr. Mercola
Beautifully red, puckeringly tart and delicious in an amazing array of dishes, from beverages to salads to main dishes, cranberries are the quintessential berry for the holidays.
While many grocery stores make them available in late fall for just this reason (and because they’re ripest between October and December), those who’ve learned to appreciate and even crave the deep flavor cranberries provide are savvy enough to buy extra and either freeze or dry them for use long after the New Year has come and gone.
Beyond their taste and versatility, this glossy little fruit has a very interesting history, and the harvesting process is unlike any other. Further, like other foods, the larger and North American version, Vaccinium macrocarpon,imparts a unique set of nutrients that make them as good for you as they are tasty.
Cranberries: Traditional Uses and Other History
In 1840, one of the most enterprising growers, Henry Hall of Massachusetts, discovered that wild cranberries growing in sandy areas at the bottom of Cape Cod Bay were larger, hardier and more abundant, which indicated the most optimal growing conditions.
Cultivation often begins unintentionally. An American ship exporting cranberries wrecked along the Dutch coast, washing crate loads of berries up onto the shore, where they took root and are farmed in the same spot to this day.
When the pilgrims came to the New World, one of the things they learned about the Indians was their ability to use plants in numerous ways.
Cranberries were used for food and to make a vibrant red dye for blankets and clothing, but also had an important function in traditional medicine for Native Americans as a poultice for healing wounds.
More recent medical practitioners understand that the astringent tannins contained in these little fruits help to contract tissues and stop bleeding. They also have compounds that are antibiotic.
The Unusual Health Aspects of Cranberries
Vitamin C is the most prominent vitamin in cranberries, with 24 percent of the Dietary Reference Intake (DRI), along with vitamin E (alpha tocopherol) and vitamin K. Cranberries are an excellent source of dietary fiber (5 grams per serving), and manganese (20 percent of the DRI). A one-half cup serving has only 25 calories.
Part of the beauty of fiber is that it helps move things along in your colon, while at the same time helps optimize your cholesterol, plus it can make you feel more full longer, so you eat less. An added bonus is that it helps control your blood sugar.
You’ve heard cranberries are helpful for urinary tract infections (UTIs) because of their acid content. However, new information has come to light indicating that powerful phytonutrients in cranberries help prevent this painful ailment. Broken down into five categories, these phytonutrients and their dominant molecules include:
- Phenolic acids — Hydroxybenzoic acids such as vanillic acids; hydroxycinnamic acids, including coumaric, cinnamic, caffeic and ferulic acids
- Proanthocyanidins — Epicatechins
- Anthocyanins — Cyanidins, peonidins and malvidins
- Flavonoids — Quercetin, kaempferol and myricetin
- Triterpenoids — Ursolic acid
Yes, every one of these is a mouthful to say, but the antioxidant, anti-inflammatory and anti-cancer properties they exert for anyone who consumes them gives them that right.
Because cranberries are grown in bogs, and flooded so they’ll float for easier harvest, they’re often also drenched in sunlight, producing anthocyanins, which increases not only their bright red color but also leads to higher concentrations of this phytonutrient. In turn, the cranberries develop increasing amounts of free radical-zapping antioxidants.
What Cranberries Can Do for You
In recent years, researchers have identified an increasing number of mechanisms that help explain the anti-cancer properties of cranberries, according to the George Mateljan Foundation,1 a not-for-profit health food site. These are now known to include:
- Blocked expression of matrix metalloproteinases, or MMPs
- Inhibition of ornithine decarboxylase enzymes (ODCs)
- Stimulation of quinone reductase enzymes, aka QRs
- Inhibition of CYP2C9s, Phase I detoxification enzymes
- Triggered apoptosis (programmed cell death) in tumor cells, including cancers of the breast, colon, lung and prostate
The Cranberry Marketing Committee2 reports that these little berries contain one of the highest rankings in terms of antioxidant content among plant-based foods, which is particularly beneficial for preventing inflammation, especially in your mouth and gums to help lower your risk of tissue-damaging inflammation from periodontal disease.
On through your stomach and colon — basically, wherever food passes through — is where the flavonols like quercetin and phenolic acids like hydroxycinnamic acid kick in, alongside PACS and anthocyanins. Further, messaging molecules called cytokines rev up and inform your cells to respond by suppressing inflammation.
Stomach ulcers, often related to overgrowth and latching on of Helicobacter pylori, a bacteria, to the stomach lining, but cranberries may prevent that in much the same way they help to prevent UTIs.
Cranberries — as Opposed to Cranberry Juice — for UTIs
The proanthocyanidins, aka PACS, in cranberries help lower the tendency for certain bacteria to cling to the walls of your urinary tract, which helps fight infections, annually experienced by more than 3 million people in the U.S., mostly women. Symptoms include pelvic pain, bloating and frequent, painful urination.
Such infections typically don’t last long, but once you’ve had one, you know what it feels like. In addition to your bladder, they can affect any part of your urinary system, including your kidneys or urethra.
Around 25 percent of women suffer through recurring UTIs, and some are concerned about going on an antibiotic because of the chance of side effects and drug resistance. While cranberry juice has been touted as the go-to substance for UTIs, whole cranberries are actually much more effective. Medical News Today reported:
“For many, the first port of call is a box of cranberry juice. However, new research suggests that while cranberry capsules can help, cranberry juice may be little more than a panacea.
As a result, the researchers propose using probiotics as a safe alternative to antibiotics in the treatment of UTIs. Probiotics are 'good' bacteria found in the digestive tract and naturally occurring in certain foods, such as fermented vegetables — including sauerkraut and kimchi — and live-cultured yogurt.”3
A study headed by Dr. Timothy Boone, vice dean of the Texas A&M Health Science Center College of Medicine in Houston, tested cranberry juice against cranberry capsules in a study involving 160 patients from ages 23 through 88.
The American Journal of Obstetrics and Gynecology,4 which published the findings, noted that the risk of urinary tract infection and catheter use is high among women undergoing elective gynecological surgery. Half received cranberry capsules; the other half took a placebo. Medical News Today reported:
“Cranberry capsules lowered the risk of UTIs by 50 percent. In the cranberry treatment group, 19 percent of patients developed a UTI, compared with 38 percent of the placebo group.”5
Cardiovascular and Related Benefits From Cranberries
Studies show cardiovascular health, oxidative stress, metabolic syndrome, diabetes mellitus and atherosclerosis (blood vessel thickening and closing) to be other areas where the phytonutrients in cranberries and other berry types can exert healing advantages.
One review named improved LDL oxidation, lipid peroxidation and glucose metabolism.
“Benefits were seen in healthy subjects and in those with existing metabolic risk factors. Underlying mechanisms for these beneficial effects are believed to include upregulation of endothelial nitric oxide synthase, decreased activities of carbohydrate digestive enzymes, decreased oxidative stress and inhibition of inflammatory gene expression and foam cell formation.”6
Immune system support is another factor improved by the phytonutrients in cranberries. They’ve been shown to lower cold and flu frequency, although this is an area that is not studied as much as their effect on your heart, which can be severely damaged by oxidative stress. It impacts your blood vessels as well, and subsequently your risk of atherosclerosis. The George Mateljan Foundation added:
“The antioxidant components of cranberries also appear to play a key role in cranberry's cardiovascular benefits. In animal studies, these antioxidant benefits have been clearly associated with decreased risk of high blood pressure.”7
Because the compounds in cranberries help optimize your cholesterol levels, your whole cardiovascular system is improved. A large part of the benefits lie in their ability to block environmental pollutants and other types of stressors that can wreak havoc in your system and attack your immune system.
How to Keep Your Cranberries Healthy
Interestingly, the blend of compounds, vitamins and minerals in cranberries is unique, as Runners World noted:
“While other fruits and berries are similar to the cranberry in that they too are packed with vitamins, nutrients and antioxidants, only the cranberry contains this unique form of PAC, which is structurally different than those found in other plant foods.
This unique structure is the reason that, despite thorough testing, polyphenol-rich grape and apple juices, raisins, green tea and chocolate have not been found to produce the same anti-adhesion activity.”8
One cup (110 grams) of chopped cranberries contains 5 grams of fiber and 4 grams of sugar, while unsweetened cranberry juice has zero fiber and 31 grams of sugar, according to Nutrition Data. Additionally, it should be noted that the estimated glycemic load of raw cranberries9 is 2, while that of unsweetened cranberry juice10 is 8.
And avoiding the consumption of too much fructose, which is implicated in dozens of serious diseases, including cancer, goes without saying.
That being said, the whole cranberry is much better for you than the juice, and there are a plethora of delicious recipes to help you out in this regard. If you use sweetener, stevia is a natural plant substance that won’t elevate your blood glucose level, unlike sucrose.11 Don’t confuse it with Splenda, which is chemically contrived in a lab and could have unpleasant side effects.
Dried cranberries known as Craisins are convenient to add to salads and other dishes, but they have loads of sugar added to them. In fact, there are 29 grams of sugar in one-quarter cup! A great alternative is making them yourself, using 12 ounces of fresh whole cranberries with 1 teaspoon of pure stevia powder and one-half cup of water. Follow the instructions for Sugar-Free Dried Cranberries at Low Carb Yum.12