Cranberries are a member of the heather family and are 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.
They’re most often consumed as juice, 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 are effective against urinary tract infections (UTIs).
This article tells you everything about cranberries, including their nutrition facts and health benefits.
Cranberries nutrition facts
Fresh cranberries are nearly 90% water; the rest is mostly carbs and fiber.
The main nutrients in 1 cup (100 grams) of raw, unsweetened cranberries are:
- 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.
These are mainly simple sugars like sucrose, glucose, and fructose.
The rest comprises 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.
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 to maintain 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.
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.
Other plant compounds of cranberries
Cranberries are very high in bioactive plant compounds and antioxidants — particularly flavonol polyphenols.
Many of these plant compounds are concentrated in the skin — and are greatly reduced in cranberry juice.
- Quercetin. The most abundant antioxidant polyphenol in cranberries. Cranberries are among the main fruit sources of quercetin.
- Myricetin. A major antioxidant polyphenol in cranberries, myricetin may have several beneficial health effects.
- Peonidin. Alongside cyanidin, peonidin is responsible for the rich red color of cranberries and some of their health effects. Cranberries are among the richest dietary sources of peonidin.
- Ursolic acid. Concentrated in the skin, ursolic acid is a triterpene compound. It’s an ingredient in many traditional herbal medicines and has strong anti-inflammatory effects.
- A-type proanthocyanidins. Also called condensed tannins, these polyphenols are believed to be effective against UTIs.
Summary: Cranberries are a rich source of various bioactive plant compounds. Some of these, such as A-type proanthocyanidins, may help prevent UTIs.
Prevention of urinary tract infections
UTIs are among the most common bacterial infections — especially among women.
They’re most often caused by the intestinal bacterium Escherichia coli (E. coli), which attaches 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.
Cranberries are among the richest fruit sources of proanthocyanidins — especially the A-type.
Several human studies indicate that drinking cranberry juice or taking cranberry supplements may reduce the risk of UTIs in children and adults.
Systematic reviews and meta-analyses support these findings, especially for women with recurrent UTIs.
In contrast, a few studies have not found any significant benefits.
Not all cranberry products are effective against UTIs. Proanthocyanidins may be lost during processing, making them undetectable in many products.
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 in treating infections. They only reduce your risk of getting them in the first place.
Summary: Cranberry juice and supplements may reduce your UTI risk. However, they do not treat this infection.
Other potential benefits of cranberries
Cranberries may have many other beneficial health effects.
Cranberries may help prevent stomach cancer and ulcers
Stomach cancer is a common cause of cancer-related death worldwide.
The bacterium Helicobacter pylori (H. pylori) infection is considered a major cause of stomach cancer, inflammation, and ulcers.
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.
One study in 189 adults suggested that drinking 2.1 cups (500 ml) of cranberry juice daily may significantly reduce H. pylori infections.
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.
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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.
In human studies, cranberry juice or extracts have proven beneficial for various heart disease risk factors. Cranberry products may help by:
- 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.
Safety and side effects of cranberries
Cranberries and cranberry products are usually safe 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 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 oxalate in your urine is one of the main risk factors.
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.
However, human studies have provided conflicting results, requiring further research.
Suggested read: Sweet potatoes: Nutrition facts & health benefits
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, limiting your consumption of cranberries and other high-oxalate foods may be sensible.
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 vitamins and minerals — and exceptionally rich in several unique plant compounds.
These compounds may help prevent UTIs, stomach cancer, and heart disease.