This post was written by Amanda Langan, RDN, LD, CNSC, Parkview Health.
Most of us have heard that drinking cranberry juice can prevent or even cure a urinary tract infection (UTI), but is it true? Multiple studies have looked at the efficacy of cranberry products specifically, cranberry juice or cranberry supplements vs antibiotic therapy treatment – and the results are mixed.1 So mixed, in fact, that in 2020, the Food and Drug Administration cited “limited” or “inconsistent” evidence to support the use of cranberry juice or cranberry supplements in the treatment of UTI’s in women.2 In this post, we’ll dive into where this home remedy came from and how cranberries might be helpful in urinary health.
The history of cranberries
Cranberries are native to North America and were first cultivated and harvested by Native Americans thousands of years ago. It is said that the Native Americans hailed the benefits of this tart berry for its kidney and urinary tract healing abilities. English settlers were also known to use cranberries to prevent scurvy, a pesky affliction caused by vitamin C deficiency. Cranberries, high in vitamin C, were the answer to these weary sea voyagers’ prayers.
Today, cranberries are grown and harvested on a massive scale that involves flooding the growing fields, transforming them into bogs. This allows the hollow, four chambered fruit to float to the surface, be scooped up and used in juices and the ever-popular cranberry sauce we are all familiar with on our Thanksgiving table.3,4
Health benefits of cranberries
So, how can this bright red berry help to treat and prevent UTIs? Glad you asked! First let’s understand what a UTI is. Bacteria, typically Escherichia coli – more commonly called E. coli, enters the urinary tract and causes infection. UTIs are more common in females due to a shorter urethra while other individuals are just more prone to developing them. Treatment usually involves a short course of antibiotics and drinking lots of fluids.
There are two key aspects of cranberries that may be helpful in preventing and possibly treating a UTI: vitamin C5 and Proanthocyanidins (PACs).1 Cranberries are high in vitamin C, an antioxidant and vital nutrient in maintaining a robust immune system. Having a strong immune system allows the body to fight off infection more easily thus preventing or reducing the occurrence of infections like a UTI.
PACs work directly in the bladder and prevent bacteria from sticking to the walls of the bladder thus preventing infection. A review published in 2023 looked at 50 studies which investigated the beneficial effect of cranberry products on the prevention and treatment of UTI. The results of these studies showed some reduction in the recurrence of UTIs in women, children and those prone to developing UTIs, but showed little benefit in adults over the age of 65, pregnant women and those with other bladder dysfunctions.1 Varied populations studied and various products used in these studies make it difficult to boil down the evidence to one specific recommendation.
Although cranberries are synonymous with UTI prevention, their protective benefits extend beyond UTI prevention. The acidic nature of cranberry juice decreases the pH of urine, thus making it more acidic which prevents the growth of bacteria. Diets high in fruits and vegetables, including cranberries, can aid in decreased kidney stone formation along with consuming adequate fluids. Including 100% cranberry juice may be beneficial in both increasing fluid consumption while preventing kidney stones.6 Cranberry benefits are even being researched for heart health, support of the gut microbiome and for cancer prevention.7
Adding cranberry to your diet
Including 100% cranberry juice or fresh or frozen cranberries as part of a healthy diet is potentially beneficial in preventing and reducing symptoms of a UTI. Current recommendations are to consume a minimum of 3 ounces of 100% cranberry juice without added sugar. Avoid cranberry cocktail options, and make sure you do 100% cranberry juice, which is very tart. Tempting as this slightly sweeter cocktail might be, it does not provide the same protective benefits as they are a combination of various juices and sugar is typically added.
Alternatively, an ounce and a half of fresh or frozen cranberries can be added to a number of dishes in order to get those protective PACs. Try adding frozen cranberries to a smoothie, your morning bowl of oatmeal, a creamy cup of yogurt or a fresh salad. Or add an ounce of 100% cranberry juice to your water bottle to liven up your daily hydration.
However you choose to incorporate this tart fruit into your diet, remember that adequate hydration and proper hygiene is key in preventing UTIs. Those who have diabetes should be careful, as fruit and fruit juice contain carbohydrates.
If you are experiencing symptoms of a UTI see your doctor right away for treatment.
Sources
- https://pubmed.ncbi.nlm.nih.gov/37947276/
- https://www.fda.gov/food/hfp-constituent-updates/fda-announces-qualified-health-claim-certain-cranberry-products-and-urinary-tract-infections
- https://www.nal.usda.gov/collections/stories/cranberries
- https://www.mountsinai.org/health-library/herb/cranberry
- https://health.clevelandclinic.org/benefits-of-cranberries
- https://www.eatrightpro.org/news-center/practice-trends/is-medical-nutrition-therapy-appropriate-for-kidney-stones
- https://cranberryinstitute.org/sites/default/files/uploads/Cranberry%20Institute%20Digital%20Berry%20Best%20Guidebook.pdf
