What Are the Benefits of Pure Cranberry Juice?

Pure cranberry juice — the unsweetened juice of cranberries — is often used to treat urinary tract infections, although whether it is effective has not been medically proven. But cranberry juice has other health attributes such as being high in vitamins and minerals, and it may improve heart health.

Cranberry, a native evergreen shrub, grows throughout North America and produces tart red berries ubiquitous to the Thanksgiving table in the form of sauce or desserts. Cranberry juice is also popular and widely available in stores, usually sweetened with added sugar or another fruit juice such as apple or grape.

Pure cranberry juice — sold as the unsweetened juice from cranberries — is often used as a dietary supplement to treat or prevent urinary tract infections (UTI), according to the National Center for Complementary and Integrative Health (NCCIH). Cranberries or the leaves from the cranberry plant have been used in traditional medicine to treat bladder, stomach and liver disorders, wounds and diabetes.

​Read more:​ What Are the Benefits of Cranberry Juice for Women?

A study published in the May 2016 issue of the magazine ​AgResearch​ showed that drinking two 8-ounce glasses of cranberry juice a day lowered several risk factors for cardiovascular disease, diabetes and stroke.

Pure cranberry juice is distinguished from other commercially produced juices by the lack of any added sugar. It is also nutritionally beneficial. The USDA shows that unsweetened cranberry juice contains the minerals calcium, magnesium, potassium, selenium, iron and zinc and is a good source of 15 essential vitamins including vitamins C, B6, B12, E, K and A as well as thiamine, niacin and riboflavin.

A 1-cup serving of unsweetened cranberry juice contains 116 calories, almost a gram of protein and 30 grams of carbohydrates, according to the USDA. Although it is unsweetened, pure cranberry juice does contain 30 grams of naturally occurring sugar.

Cranberry supplements are also available in the form of cranberry pills, extracts, powder and capsules.

​Read more:​ What Are the Health Benefits of Cranberry Pills?

Drinking pure cranberry juice is generally considered to be safe, the NCCIH notes, although drinking it in large amounts can cause stomach upset and may over time increase the risk of kidney stones. Large doses of cranberry may alter levels of warfarin, an anticoagulant (blood-thinner).

While the treatment of cranberry for UTI is often employed, an article published by the Cleveland Clinic argues that drinking cranberry juice or taking cranberry supplements probably doesn't help. Cranberries contain an active ingredient, A-type proanthocyanidins (PACs), that can prevent adherence of bacteria to the bladder wall. The article quotes urologist Courtenay Moore, MD, who says there is not enough of this active ingredient in juice or supplements to prevent or heal UTIs.

The University of Wisconsin School of Medicine and Public Health states that there is no evidence that cranberry can cure a UTI. But if you wish to try it, the school recommends drinking pure cranberry juice and mentions that drinking a cranberry juice cocktail will have no more effect on the UTI than drinking another type of fruit juice.

A Harvard University ​Health Letter​ also details that the evidence about whether cranberry juice helps prevent UTIs is mixed, reporting that many commercially available cranberry juices may be high in added sugar and calories.

If you have a urinary tract infection it's best to consult with your doctor regarding treatment. However, drinking pure cranberry juice will give you nutritional benefits unrelated to the infection from the vitamins and minerals in the juice.

​Read more:​ How to Find the Best Cranberry Juice Brands