A urinary tract infection (UTI) is an umbrella term for infections that encompass any part of the urinary tract, that is the kidneys, bladders, ureters and urethras. The occurrence of UTIs in adult males aged under 50 years is low, in comparison, adult women are 30 times more prone than men to develop a UTI due to women have shorter urethras that allow bacteria to ascend into the bladder1. In general, women have a 50% risk of UTI over their lifetime, and approximately 20–40% experience a subsequent UTI recurrence within 6 months2,3.
Uropathogenic Escherichia coli (UPEC) is the principal causative agent for the greater part of UTIs, bringing about 85% of cystitis3 (common symptoms include blood in urine, frequent urge to urinate, cramping in abdomen and back, and etc.). Other Gram-negative bacteria, for example Klebsiella pneumoniae, and some Gram-positive cocci, such as some staphylococcal and enterococcal species, appear to be also connected to the consequence of the remaining infections3. Being the second most common type of infections globally (after otitis media)3, approaches and therapeutic alternatives to antibiotics for prevention and curative treatment against UTIs are always being investigated. There is a budding attention in the search of nutritional therapies for UTI ailments rather than the conventional antibiotic treatments to counter the rising of bacterial resistance to routine antibiotic usage. Here in this article, we will discuss about the consumption of cranberry and probiotic as prophylaxis against UTIs and relief of adverse symptoms.
The red cranberry is abundant in flavonoids, especially proanthocyanidins (PACs), anthocyanidins, and flavonols, together with phenolic acids and benzoates4. Cranberry extract has been routinely and extensively recommended for UTI prevention and cure owing to the preventative activity of the naturally occurring compound, proanthocyanidins that aids in supporting healthy urinary tract function and maintaining a clean waste stream.
It is evident in the results of the meta-analysis from 7 randomised controlled trials conducted on 1498 participants in total demonstrated that cranberry reduced the risk of UTI by 26%2. Another recent study found that taking 500mg of cranberry extract twice daily for 12 months reduced the incidence of UTIs5. Several mechanisms have been proposed for the actions of cranberry against UTIs, among other possible mechanisms behind the protective effects is the ability of cranberry bioactives to interfere with the adherence or sticking of pathogens to epithelial cell receptors in urinary tract, by acting as antiadhesive agents, which emerges to be a key step in the foundation of pathogenesis of these infections6,7. If the bacteria cannot adhere to cells, they will not grow and further develop into infection.
Cranberry extract can cause issues for people taking blood-thinning medications. It contains a good amount of vitamin K and can interact with warfarin. Talk to your doctor about whether or not you should limit or avoid cranberry extract while taking your medication.
Probiotics have arisen as a novel option to the use of antibiotics against UTIs and are the subject of new research in this area. The reason behind this is high predominance of lactobacilli strain in vaginal microbiota, which plays a dynamic and frequently critical role in UTI pathology by maintaining a low pH and avoiding uropathogen colonization by competitive exclusion. As such, in a research study, the instillation of probiotic Lactobacillus in the vaginal cavity via oral administration has been shown to reduce the risk of UTIs in women by 50%8.
The combination of cranberry with some probiotic strains has also been proposed to be effective for the management of recurrent urinary tract infections9. The inhibition of the adherence of uropathogen by cranberry PACs, coupled with competitive exclusion of lactobacilli from probiotics, make perfect combination in the fight against UTIs.
- Tan CW, Chlebicki MP. Urinary tract infections in adults. Singapore Med J. 2016 Sep; 57(9): 485–490.
- Fu ZX, Liska D, Talan D, Chung M. Cranberry reduces the risk of urinary tract infection recurrence in otherwise healthy women: a systematic review and meta-analysis. The Journal of Nutrition. 2017;147:2282-2288.
- De Llano DG, Moreno-Arribas MV, Bartolome B. Cranberry Polyphenols and Prevention against Urinary Tract Infections: Relevant Considerations. Molecules. 2020 Aug; 25(15): 3523.
- Pappas E, Schaich KM. Phytochemicals of cranberries and cranberry products: characterization, potential health effects, and processing stability. Crit Rev Food Sci Nutr. 2009 Oct; 49(9):741-81.
- Caljouw MAA, Van Den Hout WB, Putter H, Achterberg WP, Cools HJM, Gussekloo J. Effectiveness of Cranberry Capsules to Prevent Urinary Tract Infections in Vulnerable Older Persons: A Double-Blind Randomized Placebo-Controlled Trial in Long-Term Care Facilities. J Am Geriatr Soc. 2014 Jan; 62(1): 103–110.
- González de Llano D, Liu H, Khoo C, Moreno-Arribas MV, Bartolomé B. Some New Findings Regarding the Antiadhesive Activity of Cranberry Phenolic Compounds and Their Microbial-Derived Metabolites against Uropathogenic Bacteria. J Agric Food Chem. 2019 Feb 27; 67(8):2166-2174.
- Blumberg JB, Camesano TA, Cassidy A, Kris-Etherton P, Howell A, Manach C, Ostertag LM, Sies H, Skulas-Ray A, Vita JA. Cranberries and Their Bioactive Constituents in Human Health. Adv Nutr. 2013 Nov; 4(6): 618–632.
- Stapleton AE, Au-Yeung M, Hooton TM, Fredricks DN, Roberts PL, Czaja CA, Yarova-Yarovaya Y, Fiedler T, Cox M, Stamm WE. Randomized, placebo-controlled phase 2 trial of a Lactobacillus crispatus probiotic given intravaginally for prevention of recurrent urinary tract infection. Clin Infect Dis. 2011 May;52(10):1212-7.
- Montorsi F, Gandaglia G, Salonia A, Briganti A, Mirone V. Effectiveness of a Combination of Cranberries, Lactobacillus rhamnosus, and Vitamin C for the Management of Recurrent Urinary Tract Infections in Women: Results of a Pilot Study. Eur Urol. 2016 Dec; 70(6):912-915.