Cranberry is an herb native to North America that has been utilized both as a food source and for medicinal purposes throughout history. Native Americans utilized this herb for treatment of bladder and kidney diseases, while English settlers used the berry for appetite loss, stomach discomfort, blood issues, and scurvy (a condition caused by vitamin C deficiency). Cranberry is commonly used today to help prevent urinary tract infections (UTIs) through the mechanism of preventing harmful bacteria from attaching to the urinary tract. Cranberry can be taken through capsules or consumed as a juice. Cranberry is high in antioxidants which help combat harmful free radicals in the body which can cause serious illnesses and aging. Cranberries contain a large amount of vitamin C, which also has a variety of health benefits.
Also known as: Agrio, Airelle à Gros Fruits, Airelle Canneberge, Airelle Européenne, Airelle Rouge, American Cranberry, Arándano, Arándano Americano, Arándano Rojo, Arándano Trepador, Atoca, Atoka, Bearberry, Canneberge, Canneberge à Feuillage Persistant, Canneberge d'Amérique, Canneberge Européenne, Cocktail au Jus de Canneberge, Cranberry Extract, Cranberry Fruit, Cranberry Fruit Juice, Cranberry Juice, Cranberry Juice Cocktail, Cranberry Juice Concentrate, Cranberry Powder, Cranberry Powdered Extract, Craneberry, Da Guo Yue Jie, Da Guo Yue Ju, Da Guo Suan Guo Man Yue Ju, European Cranberry, Extrait de Canneberge, Große Moosbeere, Gros Atoca, Grosse Moosbeere, Jus de Canneberge, Jus de Canneberge à Base de Concentré, Jus de Canneberge Frais, Kliukva, Kliukva Obyknovennaia, Kranbeere, Large Cranberry, Man Yue Ju, Man Yue Mei, Moosebeere, Mossberry, Oomi No Tsuruko Kemomo, Petite Cannberge, Pois de Fagne, Pomme des Prés, Ronce d'Amerique, Sirop de Canneberge, Small Cranberry, Trailing Swamp Cranberry, Tsuru-Kokemomo
Diseases and Conditions
There is mixed evidence concerning whether cranberry can help prevent UTIs. Cranberry has not been shown to be effective as a treatment for existing urinary tract infections. In a 2016 year-long study of one hundred forty-seven women living in nursing homes, taking two daily cranberry capsules decreased bacteria levels in their urine in the first six months of the study, but didn’t decrease their frequency of UTIs over the year of the study, compared to taking a placebo. The two capsules together contained as much proanthocyanidin, a compound that is believed to protect against bacteria, as twenty ounces of cranberry juice. A 2012 research review of thirteen clinical trials suggested that cranberry may help reduce the risk of UTIs in certain groups, including women with recurrent UTIs, children, and people who use cranberry-containing products more than twice daily. A 2012 research review of twenty-four clinical trials concluded that cranberry juice and supplements don’t prevent UTIs but many of the studies were poor quality. NCCIH-supported research is looking at the possible effects of cranberry on cancer-related anemia and tumor cells.
Cranberry, cranberry juice, and cranberry extracts are likely safe when used orally and appropriately. It is likely safe for children to consume cranberry juice. There is insufficient information on the safety of cranberry for pregnant and breastfeeding women, therefore it is best to avoid. Cranberry is generally well-tolerated although some side effects may be experienced especially when consumed in high doses. Potential side effects include:
- Skin redness
- Elevated blood glucose levels
- Gastrointestinal upset
- Vaginal itching
- Vaginal dryness
- Increased risk of uric acid kidney stone formation when consuming large amounts for a prolonged period of time.
Large doses of cranberry may alter levels of warfarin, an anticoagulant.
Supplement and Food Interactions
There are no known supplement, herb, or food interactions for cranberry.
The recommended dosage for cranberry depends on what it is being used for. The following are the specific dosage ranges for different conditions:
- For benign prostatic hyperplasia (BPH), the recommended dosage is five hundred milligrams of powdered dried cranberry fruit three times daily for six months.
- For the common cold, the recommended dosage is four hundred fifty milliliters of cranberry juice beverage daily for seventy days.
- For helicobacter pylori (H pylori), the recommended dosage is five hundred milliliters of cranberry juice daily in two divided doses for ninety days.
- For influenza, the recommended dosage is four hundred fifty milliliters of cranberry juice beverage daily for seventy days.
- For kidney stones (nephrolithiasis), the recommended dosage is five hundred milliliters of cranberry juice dissolved in one thousand milliliters of water and consumed daily for two weeks.
- For urinary odor, the recommended dosage is up to two hundred thirty-seven milliliters of cranberry juice cocktail three times daily for up to four weeks.
- For urinary tract infections (UTIs), several different doses and cranberry products have been used in different settings and in different patients populations. In patients with recurrent UTI, one recommended dosage is five hundred milligrams daily.
- In elderly, long-term care patients, the recommended dosage is four to ten ounces of cranberry juice cocktail providing twenty-six percent cranberry juice daily.
- For children aged six to sixteen years with helicobacter pylori (H pylori), the recommended dosage is two hundred milliliters of cranberry juice, with or without eighty milliliters of Lactobacillus johnsonii daily for three weeks.
- For urinary tract infections (UTIs) in children, the recommended dosage is five milliliters per kilogram of cranberry juice taken daily for six months.
Cranberry itself is a food that is consumed. It can be consumed as a juice, in sauces, in cocktails, as a dried fruit, and many other ways.