Can Cranberry Juice help prevent Urinary Tract Infections?

Author: Emily Seddon   Date Posted:15 August 2016 

A study recently published in the Journal of Functional Foods investigated effects of the combination of Vaccinium marcocarpon (cranberry) proanthocyanidins (PACs) and probiotic bacteria on the female urinary tract.

Urinary Tract Infections

Urinary tract infections (UTIs) are a common problem among the ageing population, with prevalence reaching between 20-50% in women over 65 years of age, however they can affect anyone regardless of gender and age. They are commonly caused by an acute bacterial infection in the urinary system.

Contributing factors include the shorter female urethra (as compared with male), reduced oestrogen levels, decreased urinary concentration, incomplete emptying of the bladder, incontinence, catheters and certain medications. UTIs can also impact men, especially when combined with prostatic hypertrophy, prostatitis or urethral stricture.

Symptoms of UTI may include:

If left untreated, UTIs can cause polynephritis (kidney infection) which is extremely serious and needs medical attention.

The Science:

The 2016 study found that cranberry PACs alone and in combination with the probiotic strain of Lactobacillus acidophilus prevented the invasion of E. coli, a common pathogen when found in large amounts or outside the gastrointestinal tract, in an in-vitro environment.

The study showed:

  • PACs inhibited the ability of E. coli to invade enterocytes in vitro. It was most effective in amounts between 18-36 mcg PAC/ml.
  • That the anti-bacterial activity of the PACs did not reduce the efficacy or amount of probiotics.
  • In addition to this, a probiotic blend of L. acidophilus, L. gasseri, L. plantarum, L. rhamnosus and B. animalis (without cranberry PACs) was found to prevent E. coli invasion.

This study is supported by numerous findings demonstrating that cranberry PACs and cranberry products may be effective in the prevention of uncomplicated UTIs in women and children.

Other possible interventions for the prevention of UTI development include acupuncture and vaginal oestrogen levels.

Cystitis-Care Cranberry 10g

How does cranberry work?

Vaccinnium macroparcon (cranberry) appears to work through its anti-adhesive activity - by inhibiting the adhesion of pathogens to the mucosal lining of the urinary tract, impairing colonization and subsequent infection.

Do I need to combine it with probiotics?

It may be beneficial to combine a preventative treatment of cranberry with probiotic capsules and fermented foods, including yoghurt, kefir, kombucha, sauerkraut and kimchi.

Will cranberry juice work or do I need capsules?

If the juice has high levels of proanthocyanidins, it may have the same effect as capsules (Braun & Cohen 2012). However, the naturally-present sugar in the juice may encourage the growth of pathogens.

Are there any safety issues to consider?

If pain or irritation persists for more than 48 hours, consult your doctor. The presence of blood in the urine warrants immediate medical attention.

Interactions with medications may occur. Check with your healthcare provider for any known issues.

Written by Emily Seddon
Emily Seddon

Emily (BHSc Naturopathy) is a qualified naturopath with a love of science. Growing up with a hippy mum and dad, Emily grew used to thinking outside the box for her own health. She has since completed a degree in Health Science, majoring in Naturopathy, combining that passion for healthy living with scientific and traditional evidence to help others to live happy and healthy lives.

She loves using herbal and nutritional medicine to treat ailments and lives by the philosophy of "there is no such thing as too much tea."


Leave a comment

Comments have to be approved before showing up