Cranberries contain numerous antioxidants and nutrients that provide many health benefits. Recent research has unveiled yet another benefit of cranberries: A special type of complex sugar that nourishes our gut bacteria.
Cranberries are most noted for their ability to help detach bacteria in urinary tract infections. This has been proven in research. A 2017 review from Portugal’s University of the Beira Interior found overwhelming evidence that consuming cranberries reduced UTI infections. Their meta-analysis found cranberries reduced UTIs by an average of 32 percent among numerous studies.
Another 2017 study showed that the organic acids present in cranberries seem to offer this bacteria detachment effect. The combination of malic, citric and quinic acids in cranberries appears to produce the effect of reducing the adhesion of bacteria from urinary tracts.
However, cranberries provide the opposite effect when it comes to our probiotic bacteria. Especially in the colon. Let’s take a look at the research.
Cranberries contain prebiotic
Researchers from the University of Massachusetts found in a 2017 study that cranberries contain special prebiotics called xyloglucans. These xyloglucans are, however, locked up within the cell walls of the fruit.
The researchers found that xyloglucans feed a family of bacteria called bifidobacteria. These probiotics are contained in our colon.
One of the most predominant bifidobacteria in the colon is the species Bifidobacterium longum. B. longum populate the human colon and secrete byproducts that aid in the elimination of waste. They also help protect the colon from disease-causing bacteria.
The researchers, from the university’s microbiology lab, found that B. longum benefited from consuming the xyloglucans prebiotic.
The research was led by microbiologist Dr. David Sela. Incredibly, Dr. Sela and his team found that one strain of B. longum would break down the cell walls of the fruit. This strain made the xyloglucans available to the other B. longum strains.
Yes, the bacteria worked as a team. One strain broke down the cells walls for the other strains to eat.
“A lot of plant cell walls are indigestible,” said Dr. Sela. “And indeed we cannot digest the special sugars found in cranberry cell walls called xyloglucans. But when we eat cranberries, the xyloglucans make their way into our intestines where beneficial bacteria can break them down into useful molecules and compounds.”
Earlier research hinted at cranberry’s ability to feed our gut bacteria. A paper from the 2015 Proceedings of the Cranberry Health Research Conference explored this effect of cranberry on gut bacteria. They found the myriad of different health benefits derived from cranberry may indeed be related to its ability to promote the growth of these probiotics.
“A limited but growing body of evidence from randomized clinical trials reveals favorable effects of cranberry consumption on measures of cardiometabolic health, including serum lipid profiles, blood pressure, endothelial function, glucoregulation, and a variety of biomarkers of inflammation and oxidative stress.”
As they connected the gut to these:
“Furthermore, new studies indicate synergy between these proanthocyanidins, other cranberry components such as isoprenoids and xyloglucans, and gut microbiota.”
Xylocans and other prebiotics
Xyloglucans are contained in other foods, though the research is still new. Celery contains xyloglucans, for example. So does tomato, potato, flaxseeds,
Xyloglucans are only one class of prebiotics. There are many others, including FOS (fructooligosaccharides) from fruits, GOS (galactooligosaccharides) and TOS (transgalactooligosaccharides). The latter are contained in dairy products and other foods. Whole grains also contain prebiotics – called arabinogalactans. Other prebiotics include polydextrose, inulin and psyllium.
These special food nutrients all feed different species of our probiotic bacteria. Without a good population of different species in our gut, we make our gut inviting to various disease-causing bacteria and yeasts.
Dr. Sela confirmed this point:
“Prebiotics and probiotics might interact with our own physiology to help balance the microbiome, and we already know that when things are not in balance you can get problems like inflammation. Underlying chronic inflammation can lead to or worsen many different medical conditions. That’s the health side of this kind of study of microbiology, food and health.”
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Case Adams is a California Naturopath and a Board Certified Alternative Medicine Practitioner with a PhD in Natural Health Sciences, and diplomas in Homeopathy, Aromatherapy, Bach Flower Remedies, Blood Chemistry, Clinical Nutritional Counseling and Colon Hydrotherapy. He has authored 26 books on natural healing strategies.