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Laboratory, Endocrine, & Neurotransmitter Symposium

14.5 CMEs | Live Stream available

August 28-30, 2020

Bellevue, WA

Gain additional clinical insight and treatment considerations to evaluate some of the most prevalent and challenging conditions that patients present with, including depression, anxiety, altered mental focus and stamina, sexual dysfunction, sleep disturbances, addictions and dependencies, weight management, and chronic disease. Register today at the early bird price of $379. Additional discounts available for a 2-pack of tickets (one for you, one for a colleague.)


Wellness Wednesday Webinar Series

Neurotransmitter Primer

By: Fiona Campbell, ND

June 3rd, 2020

In this month's webinar, you will review the anatomy and physiology of neurotransmitter (NT) secretion and function, examine the role of individual NTs and how imbalances present clinically, and learn to incorporate NT evaluation and treatment in your hormone balancing practice. Attendees will also obtain treatment considerations for addressing neurotransmitter imbalances, without prescription medications. Sign up today!


“An Apple a Day” in the Gut

Polyphenols and Gut Bacteria


By Julia Malkowski, ND, DC | May 27, 2020

The long-held adage that an apple a day keeps a doctor away is worthy for several reasons including negative caloric value, fiber and polyphenol content. Polyphenols have demonstrated anti-cancer, anti-oxidant, anti-microbial, and anti-inflammatory properties in human health. The significant benefits of polyphenols on systemic health is largely dependent upon the gut microbiota that metabolize polyphenols. The gut microbiota itself is also directly and positively influenced by polyphenols in a mutualistic relationship.

Fruits, vegetables, certain herbs, seeds, cereals, coffee, tea, cocoa and wine are good sources of polyphenols. Polyphenols must be metabolized within the gastrointestinal tract to bioavailable health promoting metabolites. Hydrolysis and conjugation reactions of polyphenols takes place in the small intestine. The metabolites not absorbed in the small intestine then travel to the colon where they undergo metabolism via gut bacteria. Every polyphenol metabolite is consumed by the gut bacteria. Specific bacteria, such as Clostridium, Eubacterium serum and Bifidobacterium dentium, are involved in the metabolism of polyphenols. The renowned benefits of green tea are due to the polyphenols largely metabolized by Eubacterium species. The polyphenols from the red, purple and blue pigmentation of fruits and vegetables have low bioavailability, therefore we are reliant upon gut bacteria for their utilization. The microbe-modified polyphenols are absorbed, then undergo methylation, sulfation and glucuronidation prior to eliciting their myriad health benefits.

Polyphenols interact with the gut bacteria through multiple actions which modulate microbial diversity and abundance. Polyphenols and their aromatic metabolites modulate the composition of gut bacteria via prebiotic effects and even exhibit antimicrobial activities against pathogenic bacteria. Due to their high molecular weight, polyphenols work synergistically as a prebiotic with soluble fiber. One type of polyphenol, a catechin found in red wine, blackberries and apples, inhibits the growth of Clostridium histolyticum and promotes the growth of beneficial E. coli. Catechin has been shown to have bacteriostatic activity against Klebsiella pneumonie, Salmonella choleraesis, Pseudomonas aeruginosa and Staphylococcus aureus. Bacteriostatic polyphenols are derived from common plant foods, and one study identified a bacteriostatic polyphenol from the skin of several nuts.

Polyphenols derived from chocolate, green tea, blackcurrant and grape seed extracts have all been shown to increase Lactobacillus species while suppressing growth of certain Clostridium species. Wild blueberries were shown to significantly increase Bifidobacterium species. Polyphenols derived from red wine have been shown to significantly increase the abundance of Bacteroides, Lactobacillus and Bifidobacterium species. The polyphenol-induced abundance of Lactobacillus and Bifidobacterium species has indeed been associated with amelioration of inflammation, as indicated by lower levels of C-reactive protein.

Gut bacteria and polyphenols have an essential mutualistic relationship that significantly benefits health. The myriad of systemic health benefits of polyphenols is closely linked to their metabolism by gut bacteria. While gut bacteria influence polyphenol metabolism, the polyphenols in turn positively affect the microbial community. In addition to diet-derived microbiota accessible carbohydrates (soluble fiber), habitual intake of an abundance of diverse polyphenols contributes to normobiosis and optimal health.


Cardona, F., Andres-Lacueva, C., Tulipani, S., Tinahones FJ., Queipo-Ortuno, MI., (2013). Benefits of polyphenols on gut microbiota and implications in human health. J Nutr Biochem, Aug;24(8):1415-22.

Marín, L., Miguélez, E. M., Villar, C. J., & Lombó, F. (2015). Bioavailability of dietary polyphenols and gut microbiota metabolism: antimicrobial properties. BioMed research international, 2015, 905215.

Ozdal, T., Sela, D. A., Xiao, J., Boyacioglu, D., Chen, F., & Capanoglu, E. (2016). The Reciprocal Interactions between Polyphenols and Gut Microbiota and Effects on Bioaccessibility. Nutrients, 8(2), 78.

Disclaimer: All information given about health conditions, treatment, products, and dosages are for educational purposes only and do not constitute medical advice.