In the news: Health Benefits of Cranberry

New Studies on Health Benefits of Cranberry

If you’re like most Americans, cranberry sauce is a staple on your menu for Thanksgiving dinner. But the potential health benefits of this little red berry native to North America extend throughout the year. Cranberry, for example may help women and children prevent urinary tract infections (UTIs) and help type 2 diabetics in controlling blood sugar levels.

Although antibiotics are without a doubt one of the greatest advances in medicine, their widespread use has led to resistant bacteria that are harder to treat. Pneumonia and many urinary tract infections (UTIs) are now among the common drug-resistant infections. Not only have scientists been trying to develop new antibiotics, there is also great research interest in finding strategies to help prevent some of these infections in the first place.

Current clinical evidence clearly indicates a possible benefit overall from the use of cranberries against UTIs. Consuming cranberries seems to prevent bacteria from attaching to the epithelial cells lining the urinary tract, for example. But the effectiveness of cranberry in certain segments of the population at increased risk for UTIs has been questioned.

A new review of cranberry (1) concludes that cranberry has a role in preventing recurring UTIs in women over 45. Older and midlife women are more likely to get UTIs because of the changing hormonal environment during and after menopause. The review looked at studies on the prevention of UTIs and assessed the efficacy and safety of various non-antibiotic strategies such as vitamin C, d-mannose, lactobacilli and estrogens.

The reviewers found evidence to support use of estrogens in postmenopausal women, and cranberry capsules in women aged 45 and older for the prevention of UTIs. Keep in mind that along with good hygiene practices, drinking plenty of water is also key to flushing bacteria out of the bladder and urinary tract.

Adults aren’t the only group concerned with UTIs. Kids can contract UTIs as well. In fact, UTIs are very common during childhood and about 10% to 30% of children experience recurrent UTIs after their first infection. Until recently, antibiotic prophylaxis was often recommended for children with recurrent UTI.

Pediatric researchers in Greece explored the efficacy and safety of cranberry capsules in children aged 2-14 with a history of recurrent UTIs2. Compared to the control group, children taking cranberry had a lower percentage of UTIs, experienced less days on antibiotics, and fewer of them required antimicrobial drugs to prevent recurrent infections. The authors suggest that standardized cranberry extract be considered in some children with recurrent UTIs as an alternative prevention method and one that helps avoid prolonged antibiotic treatment.

Cranberry, Blueberry & Type 2 Diabetes

Preclinical and clinical studies have suggested that cranberries as well as blueberries can also be helpful for diabetics in managing blood sugar levels. A recent review of 7 trials was carried out by university researchers in Brazil (3).

The investigators point out that many dosage forms were used in the clinical studies – juice, whole berries, dried berries and extracts, and highlight the results of several studies.

Daily cranberry juice (240 mL or an 8oz. glass) consumption for 12 weeks and blueberry extract or powder supplementation (containing 9.1 to 9.8 mg of anthocyanins, respectively) for 8 to 12 weeks showed a beneficial effect on glucose control in type 2 diabetic patients. Those results indicate a promising use of these berries in managing type 2, although more studies are required to better understand the mechanisms involved.

References

1. Gill CM, et al. A review of nonantibiotic agents to prevent urinary tract infections in older women. J Am Med Dir Assoc S1525-8610(19)30379-2 published online June 18, 2019.
2. Dotis J, et al. Cranberry standardized capsules may prevent recurrences of urinary tract infections in children. Clin Pediatri. 1: 1007, 2018
3. Rocha DMUP, et al. Effects of blueberry and cranberry consumption on type 2 diabetes glycemic control: A Systematic Review. Crit Rev Food Sci Nutr. 59:1816-28, 2019.