The Misguided Approach to Polyphenolic Enhancement (and What to Do Instead)

When we think of polyphenols, we think of well-known phytonutrients such as curcumin, quercetin, rutin and resveratrol found in plant-based foods that provide the body with antioxidant protection against free radical damage and oxidative stress. Common practice is to isolate and concentrate these compounds in an attempt to enhance their absorption and provide greater therapeutic outcomes rather than simply consume them in their whole plant form. This approach, which encompasses an old model of botanical medicine understanding, is limited. This is because when polyphenols are isolated from their whole plant form, they naturally have low solubility, stability, and poor bioavailability.¹

What the Research Shows

Newer research shows that polyphenols in their isolated form are highly reactive and considered toxic at concentrated levels. As a result, the body interprets isolated polyphenols as xenobiotics and activates Phase II detoxification to rapidly excrete and eliminate these molecules.² So, when you recommend an isolated polyphenolic supplement such as curcumin, quercetin, rutin or resveratrol by itself, you are essentially accelerating its conjugation and elimination, thereby rendering it less bioavailable and less bioactive in your patients.

To overcome this, polyphenols have been added to delivery systems such as liposomes and phytosomes to bypass the body’s digestive system and enhance their bioavailability. In vitro studies have shown that these enhanced delivery approaches do positively affect bioavailability, but research has yet to prove enhanced bioactivity in human clinical application.³

Why Phospholipid-Enhanced Delivery Systems Are Not the Answer

Phospholipid enhanced delivery systems of polyphenols, such as phytosomes and liposomes, are designed to target the bloodstream in an attempt to enhance bioavailability. In doing so, they are resistant to normal digestive processes, including direct interaction with the gut microbiome.^4-5 It has been shown in both in vitro and in vivo studies that polyphenols share a bidirectional relationship with the gut microbiome, where dietary polyphenols influence gut microbiota diversity and composition and in turn, intestinal microbiota metabolize polyphenols into bioactive metabolites that influence host health.⁶

These metabolites have been extensively studied for their therapeutic activity including anti-inflammatory, antioxidant, anti-diabetic, anti-obesity, and antimicrobial properties. It has also been shown that polyphenolic bioactive metabolites have the potential to modulate regulatory pathways involved in intestinal barrier function, as well as upregulate nuclear factor erythroid 2-related factor 2 (Nrf2), downregulate nuclear factor kappa B (NF-kβ), and reduce the production of pro-inflammatory cytokines IL-8, IL-1β, and tumor necrosis factor alpha (TNF-α).⁷

The Bottom Line

What the science now tells us is that once a polyphenol is isolated from its whole-plant form, it is no longer considered a plant-based food. Nature has already done the bioavailability work for us by producing plant-based foods with high chemical diversity and biochemical specificity that get biosynthesized naturally by the body’s own digestive processes.⁸

It is time that we stop focusing on isolating polyphenols from their natural state and applying delivery systems that are completely foreign to the body’s natural biological processes and instead, focus on utilizing whole-plant bioactive constituents, such as a complete matrix form, to enhance bioavailability and bioactivity of polyphenols in our patients as nature intended.

Claire Kacena, DC is the MSK Solutions and Immune Foundations Clinical Brand Manager at Lifestyle Matrix Resource Center and a board-certified chiropractor.  She obtained her Bachelor of Science degree from Loyola University Chicago in 2010 and then went on to receive her Doctor of Chiropractic from National University of Health Sciences in 2015. Currently, Dr. Kacena is pursuing her diplomate in clinical nutrition.

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