The Proven Health Benefits of Cranberries

Cranberries are rich in antioxidants and fiber and offer many potential health benefits. The tiny, tart fruit may help prevent urinary and gastrointestinal tract infections, reduce the risk of heart disease, boost oral health, and improve blood glucose levels in people with type-2 diabetes.

While most research has studied juice and supplements, cranberries can also be eaten fresh or dried. Cranberry supplements are generally considered safe, but people with a higher risk of kidney stones or who take certain medications, as well as those who are pregnant or breastfeeding, should consult their healthcare provider before taking them.

Proven Health Benefits

Cranberries are often touted as a superfood because they are rich in nutrients like vitamins C, E, and K, as well as fiber. They also contain many phytochemicals, compounds that have antimicrobial and antioxidant properties.

Research shows that cranberries (in various forms) have the following health benefits:

• Prevent urinary tract infections: Cranberries contain compounds called proanthocyanidins (PACS) that prevent the bacteria that commonly cause UTIs from attaching to cells in the urinary tract and causing infection. Research shows that cranberry may help prevent recurring urinary tract infections (UTIs). Cranberry is associated with an average 30% decreased risk of recurrent UTIs in women, children, and people who have undergone bladder radiotherapy.
• Prevent GI tract infections: The PACS in cranberries may also play a role in suppressing stomach or intestinal infections caused by a bacteria called Helicobacter pylori (H. pylori). A study of 522 adults with H. pylori showed that those who drank cranberry juice with a high amount of PACS twice a day for eight weeks had a 20% lower infection rate than those who took cranberry powder or a placebo.
• Prevent bladder inflammation: Research shows that taking cranberry capsules significantly lowered the incidence of cystitis (bladder inflammation) in men undergoing prostate cancer treatment as well as women with chronic cystitis.
• Improve blood glucose levels: A review of 22 studies concluded that cranberry may lower fasting blood sugar and hemoglobin A1c (a test that measures average blood sugar levels over the past three months) in people with type 2 diabetes. It's thought that the polyphenols in cranberry are responsible for this blood sugar-lowering effect.
• Boost heart health: Cranberry may improve some risk factors for heart disease, such as blood pressure and body mass index (BMI). It may also increase high-density lipoprotein (HDL, or "good" cholesterol) in people under 50 years old.
• Improve oral health: PACs like those found in cranberries may be beneficial in preventing tooth decay and gingivitis.

Other Potential Benefits

Cranberry has also been studied in clinical trials for the following conditions, but more data is needed before it can be recommended:

• Rheumatoid arthritis
• Slowing cancer progression
• Overactive bladder
• Metabolic syndrome
  

Nutritional Profile

Cranberries are rich in fiber and several important vitamins and minerals. The following nutrition is found in 1/2 cup (100 grams) of raw cranberries:

How to Use It

Cranberry can be easily incorporated into your diet. Here's how:

• Add fresh cranberries (which are not typically consumed raw due to their acidity ) to recipes, such as muffins.
• Look for dairy products and cereals that contain dried cranberries.
• Add cranberry extract or powder to smoothies.
• Take a cranberry supplement, which is available in capsule and tablet form.

Side Effects

Cranberry isn't associated with many side effects. However, due to its high sugar content, sweetened cranberry juice may cause stomach upset or diarrhea, particularly in children.

Precautions

Ask your healthcare provider before beginning cranberry supplementation if you:

• Have a history of kidney stones: Cranberry supplements increase the concentration of oxalate in the urine. Although the research is mixed, some studies suggest this may increase the formation of kidney stones.
• Are pregnant and/or breastfeeding: There isn't much safety data about cranberry use during pregnancy or breastfeeding.

Interactions

Cranberry may interact with the following drugs:

• Warfarin: Some research has found an association between high doses of cranberry and an increased risk of bleeding in people who take the anticoagulant (blood thinner) warfarin.
• Tacrolimus: Cranberry has been shown to decrease blood levels of tacrolimus, an immune system suppressant that may be used for eczema or to prevent organ transplant rejection.
  

Summary

Cranberry juice may help prevent recurrent UTIs, prevent oral decay, and improve heart health. Some evidence also supports the use of cranberry in preventing intestinal infections caused by H. pylori and lowering blood glucose levels in people with type-2 diabetes.

If you decide to use it, remember that cranberry may interact with the prescription drugs warfarin and tacrolimus. Cranberry supplements may not be advised for people at risk of kidney stones or those who are pregnant or breastfeeding.