Cranberries are a good source of certain vitamins and minerals, as well as several unique plant compounds that may help prevent UTIs, stomach cancer, and heart disease.

Cranberries are a member of the heather family and related to blueberries, bilberries, and lingonberries.

The most commonly grown species is the North American cranberry (Vaccinium macrocarpon), but other types are found in nature.

Due to their very sharp and sour taste, cranberries are rarely eaten raw.

In fact, they’re most often consumed as juice, which is normally sweetened and blended with other fruit juices.

Other cranberry-based products include sauces, dried cranberries, and powders and extracts used in supplements.

Cranberries are rich in various healthy vitamins and plant compounds, some of which have been shown to be effective against urinary tract infections (UTIs).

This article tells you everything you need to know about cranberries, including their nutrition facts and health benefits.

Fresh cranberries are nearly 90% water, but the rest is mostly carbs and fiber.

The main nutrients in 1 cup (100 grams) of raw, unsweetened cranberries are (1Trusted Source):

  • Calories: 46
  • Water: 87%
  • Protein: 0.4 grams
  • Carbs: 12.2 grams
  • Sugar: 4 grams
  • Fiber: 4.6 grams
  • Fat: 0.1 grams

Carbs and Fiber

Cranberries are primarily composed of carbs and fiber (1Trusted Source).

These are mainly simple sugars, such as sucrose, glucose, and fructose (2Trusted Source).

The rest is made up of insoluble fiber — such as pectin, cellulose, and hemicellulose — which pass through your gut almost intact.

Cranberries also contain soluble fiber. For this reason, excessive consumption of cranberries may cause digestive symptoms, such as diarrhea.

On the other hand, cranberry juice contains virtually no fiber and is usually diluted with other fruit juices — and sweetened with added sugar (3Trusted Source).

Vitamins and Minerals

Cranberries are a rich source of several vitamins and minerals, especially vitamin C.

  • Vitamin C. Also known as ascorbic acid, vitamin C is one of the predominant antioxidants in cranberries. It is essential for the maintenance of your skin, muscles, and bone.
  • Manganese. Found in most foods, manganese is essential for growth, metabolism, and your body’s antioxidant system.
  • Vitamin E. A class of essential fat-soluble antioxidants.
  • Vitamin K1. Also known as phylloquinone, vitamin K1 is essential for blood clotting.
  • Copper. A trace element, often low in the Western diet. Inadequate copper intake may have adverse effects on heart health (4Trusted Source).
SUMMARY

Cranberries are primarily made up of carbs and fiber. They also boast several vitamins and minerals, including manganese, copper, and vitamins C, E, and K1. Keep in mind that cranberry juice has almost no fiber.

Cranberries are very high in bioactive plant compounds and antioxidants — particularly flavonol polyphenols (2Trusted Source, 5Trusted Source, 7Trusted Source).

Many of these plant compounds are concentrated in the skin — and are greatly reduced in cranberry juice (3Trusted Source).

SUMMARY

Cranberries are a rich source of various bioactive plant compounds. Some of these, such as A-type proanthocyanidins, may help prevent UTIs.

UTIs are among the most common bacterial infections — especially among women (15Trusted Source).

They’re most often caused by the intestinal bacterium Escherichia coli (E. coli), which attaches itself to the inner surface of your bladder and urinary tract.

Cranberries contain unique phytonutrients known as A-type proanthocyanidins or condensed tannins.

A-type proanthocyanidins prevent E. coli from attaching to the lining of your bladder and urinary tract, making cranberries a potential preventive measure against UTIs (13, 16Trusted Source, 17Trusted Source, 18Trusted Source, 19Trusted Source).

In fact, cranberries are among the richest fruit sources of proanthocyanidins — especially the A-type (14Trusted Source, 20Trusted Source).

A number of human studies indicate that drinking cranberry juice or taking cranberry supplements may reduce the risk of UTIs in both children and adults (22Trusted Source, 23Trusted Source, 24Trusted Source, 25Trusted Source, 26Trusted Source, 27Trusted Source, 28Trusted Source).

Systematic reviews and meta-analyses support these findings, especially for women with recurrent UTIs (29Trusted Source, 30Trusted Source, 31Trusted Source).

In contrast, a few studies have not found any significant benefits (32Trusted Source, 33Trusted Source, 34Trusted Source).

Not all cranberry products are effective against UTIs. In fact, proanthocyanidins may be lost during processing, making them undetectable in many products (35Trusted Source).

On the other hand, cranberry supplements — which contain sufficient amounts of A-type proanthocyanidins — may be a useful preventive strategy.

If you suspect that you have a UTI, talk to your healthcare professional. The primary course of treatment should be antibiotics.

Keep in mind that cranberries are not effective for treating infections. They only reduce your risk of getting them in the first place.

SUMMARY

Cranberry juice and supplements may reduce your risk of UTIs. However, they do not treat this infection.

Cranberries may have a number of other beneficial health effects.

Prevention of Stomach Cancer and Ulcers

Stomach cancer is a common cause of cancer-related death worldwide (36Trusted Source).

Infection by the bacterium Helicobacter pylori (H. pylori) is considered a major cause of stomach cancer, stomach inflammation, and ulcers (37Trusted Source, 38Trusted Source, 39Trusted Source, 40Trusted Source).

Cranberries contain unique plant compounds known as A-type proanthocyanidins, which may cut your risk of stomach cancer by preventing H. pylori from attaching to the lining of your stomach (41Trusted Source, 42Trusted Source, 43Trusted Source, 44Trusted Source).

One study in 189 adults suggested that drinking 2.1 cups (500 ml) of cranberry juice daily may significantly reduce H. pylori infections (45Trusted Source).

Another study in 295 children found that daily consumption of cranberry juice for 3 weeks suppressed the growth of H. pylori in about 17% of those infected (41Trusted Source).

Heart Health

Heart disease is the leading cause of death worldwide.

Cranberries contain various antioxidants that may be beneficial for heart health. These include anthocyanins, proanthocyanidins, and quercetin (46Trusted Source, 47Trusted Source, 48Trusted Source, 49Trusted Source).

In human studies, cranberry juice or extracts have proven beneficial for various heart disease risk factors. Cranberry products may help by (50Trusted Source, 51Trusted Source, 52Trusted Source, 53Trusted Source, 54Trusted Source, 55Trusted Source):

  • increasing your levels of HDL (good) cholesterol
  • lowering levels of LDL (bad) cholesterol in people with diabetes
  • protecting LDL (bad) cholesterol from oxidation
  • decreasing stiffness in blood vessels among people with heart disease
  • lowering blood pressure
  • decreasing blood levels of homocysteine, thus cutting your risk of inflammation in blood vessels

That said, not all studies found similar results.

SUMMARY

If consumed regularly, cranberries or cranberry juice may reduce your risk of stomach cancer. The juice and extract also improve several risk factors for heart disease, including cholesterol levels and blood pressure.

Cranberries and cranberry products are usually safe for most people if consumed in moderation.

However, excessive consumption may cause stomach upset and diarrhea — and may also increase the risk of kidney stones in predisposed individuals.

Kidney Stones

Kidney stones form when certain minerals in your urine reach high concentrations. It is often very painful.

You can minimize your risk through your diet.

Most kidney stones are made of calcium oxalate, so excessive amounts of oxalate in your urine is one of the main risk factors (56Trusted Source).

Cranberries — especially concentrated cranberry extracts — may contain high levels of oxalates. For this reason, they are considered a risk factor for kidney stones when consumed in high amounts (57Trusted Source, 58Trusted Source, 59Trusted Source).

However, human studies have provided conflicting results and the issue requires further research (57Trusted Source, 59Trusted Source).

Susceptibility to developing kidney stones varies between individuals. In most people, cranberries probably do not significantly affect kidney stone formation.

Still, if you are prone to getting kidney stones, it may be sensible to limit your consumption of cranberries and other high-oxalate foods.

SUMMARY

High consumption of cranberries may increase the risk of kidney stones in predisposed individuals.

Cranberries are widely consumed dried, as a juice, or in supplements.

They’re a good source of a few vitamins and minerals — and exceptionally rich in several unique plant compounds.

Some of these compounds may help prevent UTIs, stomach cancer, and heart disease.