Health Benefits of Cranberries

by Diane, M.P.H, M.S.

Cranberries are a wonderful source of Vitamin C, a good source of Vitamins E, K, and A, dietary fiber, lutein, zeaxanthin, folate, and minerals like manganese, copper, and potassium, as well as, other essential micronutrients that support good health. Naturally low in calories, fat, and sodium, cranberries play a significant role in preventing urinary tract infections, reducing the risk of gum disease and tooth decay, and possibly other inflammatory conditions. 

Why are cranberries so good for you?

  • Cranberries are rich in phytonutrients (naturally-derived plant compounds), especially proanthocyanidin antioxidants*, which are essential for good health. They surpass nearly every fruit and vegetable, including strawberries, spinach, broccoli, red grapes, apples, raspberries, and cherries, in offering the most disease-fighting antioxidant activity, the strongest effect on inhibiting human cancer cells, and the most powerful phytochemicals! A unique variety of antioxidants (phenolic antioxidants, proanthocyanidin antioxidants, anthocyanin antioxidants, flavonoid antioxidants, and triterpenoid antioxidants) and combination of three antioxidant nutrients (resveratrol, piceatannol, and pterostilbene) are found exclusively in whole cranberries. These phytonutrients provide maximal antioxidant benefits only when consumed in combination with each other, and also, only when consumed with conventional antioxidant nutrients present in cranberry like manganese and vitamin C. When cranberry processing disrupts this antioxidant combination, health benefits are decreased. Studies have shown that it is the overall blend of cranberry antioxidants that provides the strongest health benefits. (One cup of whole cranberries has an Oxygen Radical Absorbance Capacity (ORAC) score of 9584 µmol TE units per 100 g, one of the highest in the category of edible berries. Only blueberries 0ffer more [wild varieties have 13,427; cultivated blueberries have 9,019]).

  • Provide an excellent source of 2 types of important phytochemicals:
    • Flavonoids (anthocyanins, flavonols, proanthocyanidins): Research suggests that these three phytochemicals work together to suppress the growth of human cancer cells and decrease the risk of atherosclerosis (hardening of the arteries).
    • Phenolic acids (hydroxycinnamic acid)
  • Help prevent and treat bladder/urinary tract infections: Cranberries contain proanthocyanidins (PACs), that seem to make it more difficult for certain types of pathogenic bacteria, like E. coli, the bacteria responsible for 80-90% of urinary tract infections, to latch onto the bladder and urinary tract lining. Women who drink cranberry juice tend to suffer fewer symptomatic urinary tract infections (UTIs). By making it more difficult for unwanted bacteria to cling to the bladder and urinary tract lining, PACs help prevent proliferation of bacterial populations that could result in outright infection. The age group in which researchers are least sure about this process involves children—it’s not clear when cranberry’s health benefits fully extend to this age group. Benefits have been most pronounced in middle-aged women who have experienced recurrent UTIs. In some studies, UTIs in this age and gender group have been reduced by more than 1/3 through dietary consumption of cranberry juice.

  • Cranberry’s antioxidant and anti-inflammatory phytonutrients (ex., flavonoids) support digestive health and have been associated with a reduced risk of colon cancer and periodontal disease.
  • Optimize the balance of bacteria in our digestive tract: Participants in a recent study who drank 2 ounces of cranberry juice daily over the course of 3 months were able to increase the relative amount (%) of Bifidobacteria in their digestive tract while maintaining other bacterial types (Bifidobacteria are typically considered to be a desirable and “friendly” type of bacteria). As a result, the microbial environment of the digestive tract improved.
  • Regular cranberry juice consumption for months been associated with a significant reduction in Helicobacter pylori bacteria which increase the risk of stomach cancer and ulcers: Stomach ulcers are often related to overgrowth of one particular type of stomach bacteria (Helicobacter pylori or H. pylori) on the stomach lining. Just as PACs help prevent the adhesion of certain bacteria to the lining of the bladder and urinary tract, PACs seem to prevent attachment of H. pylori to the stomach wall. Cranberry juice may help reduce the risk of gum disease and stomach ulcer in this way. Cranberries are the only fruit that contain these unique and powerful PACs.
  • Anti-inflammatory benefits: Dietary consumption of cranberry has been shown to reduce the risk of chronic, unwanted inflammation in the stomach, large intestine (colon) and cardiovascular system (especially blood vessel linings). For the cardiovascular system and many parts of the digestive tract (including the mouth, gums, stomach, and colon) cranberry has been shown to provide important anti-inflammatory benefits. Phytonutrients in cranberry are especially effective in lowering our risk of unwanted inflammation, and virtually all of the phytonutrient categories represented in cranberry are now known to play a role. These phytonutrient categories include PACs, anthocyanins (the flavonoid pigments that give cranberries their deep shades of red), flavonols like quercetin, and phenolic acid (hydroxycinnamic acids).
  • May improve oral health and reduce the risk of periodontal (gum) disease:
    • PACs prevent plaque formation and the development of cavities on teeth by interfering with the ability of gram-negative bacterium, Streptococcus mutans, to stick to the tooth surface, in a way similar to the mechanism preventing urinary tract infections.
    • The anti-inflammatory properties of cranberry can help lower the risk of periodontal disease. Chronic, excessive levels of inflammation around the gums can damage tissues that support our teeth. This kind of inflammation gets triggered by overproduction of certain pro-inflammatory cytokines (messaging molecules) which “tell” cells to mount an inflammatory response. As messages are sent more frequently, the inflammatory response becomes greater. Phytonutrients in cranberry help reduce this inflammatory cascade of events precisely at the cytokine level.
  • Lower the risk of high blood pressure: Animal studies with rats and mice indicate that cranberry antioxidants benefit the cardiovascular system by reducing oxidative stress inside blood vessels which could eventually damage blood vessels and elevate blood pressure. Additionally, antioxidants may lessen or prevent overconstriction of blood vessels which would increase blood pressure.
  • Promote a healthy cardiovascular system: The combination of antioxidants and anti-inflammatory phytonutrients in cranberries may prevent cardiovascular disease by counteracting against cholesterol plaque formation in the heart and blood vessels. These compounds also appear to lower LDL (bad) cholesterol levels and increase HDL (good) cholesterol levels in the blood. Oxidative stress and chronic inflammation place blood vessel walls at great risk of damage. Once damaged, blood vessels walls can undergo a process of plaque formation, and the risk of atherosclerosis (blood vessel wall thickening, stenosis, and blocking) can be greatly increased. Dietary intake of cranberries and cranberry juice (in normal everyday amounts, unchanged for research study purposes) has been shown to prevent the activation of two enyzmes that are pivotal in the atherosclerosis process by blocking activity of a pro-inflammatory cytokine- messaging molecule called tumor necrosis factor alpha (TNF-alpha). These anti-inflammatory benefits of cranberry appear to be critical components in the cardiovascular protection offered by this amazing fruit.
  • Help lower LDL (bad) cholesterol and total cholesterol, but raise HDL (good) cholesterol.
  • Consumption of cranberries turns urine acidic: This, together with the bacterial anti-adhesion property of cranberry juice helps prevent the formation of alkaline (calcium ammonium phosphate) stones in the urinary tract by working against proteus bacterial-infections.
  • Contain hippuric acid, which has an antibacterial effect on the body, as well as natural antibiotic ingredients.
  • May improve immunity and reduce the risk of colds and the flu.
  • May help to trigger programmed cell death in tumor cells (apoptosis) and reduce the risk of cancer, especially breast, colon, lung, and prostate cancer: Chronic excessive oxidative stress (from lack of sufficient antioxidant support) and chronic excessive inflammation (from lack of sufficient anti-inflammatory compounds) are two key factors which raise the risk of cancer. The cancer-related benefits of cranberries are not surprising, since they are rich in both antioxidant and anti-inflammatory nutrients.
  • Whole cranberries consumed in dietary form, in comparison with purified cranberry extracts consumed in either liquid or dried supplement form, do a better job of protecting our cardiovascular system and liver: It is the synergy among cranberry nutrients (rather than individual cranberry components) that is responsible for cranberry’s health benefits. This synergy is only found in the whole berry when consumed as food. The importance of “whole foods” in our diet definitely applies to the antioxidant, anti-inflammatory, and anti-cancer benefits of cranberry.

There is a clear association between a diet high in fruits and vegetables and a low risk of chronic disease. Fruits and vegetables contain phytonutrients, naturally derived from plant compounds. In particular, antioxidants, a group of extremely beneficial phytonutrients, are increasingly being shown to contribute to improving human health. For optimum health try to eat 5-10 servings of various fruits and vegetables each day.

Safety concern for patients with oxalate stones or on Coumadin:
  • Cranberries contain oxalic acid, a substance naturally found in many fruits, vegetables, grains, nuts and seeds (ex., spinach, rhubarb, chard, beets, beet leaves, bananas, star fruit) which may crystallize as oxalate stones in the urinary tract in some individuals. People with a known history of oxalate urinary tract stones should limit intake of cranberries and, especially vegetables belonging within the Brassica family. Adequate water intake is advised to dilute and maintain normal urine output and reduce the risk of such stones. If you have kidney stones, consult your doctor before self-treating with cranberry juice or cranberry products.
  • People taking Coumadin (Warfaran) should avoid or minimize eating cranberries, drinking cranberry juice, or taking cranberry containing herbal products. Cranberry products destabilize Coumadin and increase its anticoagulant effect on the body which increases the risk of severe bleeding problems. Avoid or drink only small amounts of cranberry juice when taking warfarin.

* Antioxidants: Important compounds in plants which protect the body from “free radicals,” harmful oxidants in cigarette smoke, pollutants, unhealthy foods, and environmental toxins. Free radicals cause cell damage which weakens the immune system and may increase the risk of several diseases. Antioxidants reduce the effect of free radical oxidants by binding with them to decrease their destructive tendencies and repairing the damage already done. Research has shown that antioxidants help to maintain healthy cells, tissues, and arteries.

Medical disclaimer: The information on this website is intended solely for the general information for the reader. It is not to be used to diagnose specific health problems or for treatment purposes. It is not a substitute for medical care provided by a licensed and qualified health professional. Please consult your health care provider for any advice on medications.


  1. “Cranberries: #1 in Antioxidants and #1 in Proanthocyanidins (PACs).” USDA Oxygen Radical Absorbance Capacity (ORAC) of Selected Foods. 2007.
  2. “Cranberries-What’s New and Beneficial About Cranberries?” Whole Foods: The World’s Healthiest Foods. 2013. (Source:
  3. Davis, Jeanie Lerche. “Cranberries: Year-Round Superfood. You Can Get the Antioxidant Benefits of Cranberries Long After the Holidays.” WebMD, Inc. Feature Archive. 2007. Reviewed on September 29, 2009.


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