The Solgar-funded study highlights the polyphenol mechanisms that, through their intestinal microbiota interaction, promote bacterial genera involved in cognitive functions that include Akkermansia, Lactobacilli, and Bifidobacteria.
Discussing the role of cocoa flavanols in sports nutrition the paper authors say it is “necessary to clarify the interactions with the intestinal microbiota to understand the mechanisms at the basis of multiple beneficial effects exerted by these molecules, especially at the cardiometabolic and psycho-cognitive level.
“Cocoa polyphenols are absorbed only minimally in the small intestine,” they write. “At the same time, most of them, reach the colon and undergo metabolism by the intestinal microbiota to form small bioactive molecules that carry out their beneficial properties.
“Out of the many gut microbial species, Escherichia coli, Bifidobacterium sp., Lactobacillus sp., Bacteroides sp., Eubacterium sp., are known to be mainly responsible for the cocoa’s polyphenol metabolism.”
Cocoa flavanols are a class of polyphenols that are present in foods such as cocoa, tea, vegetables, and fruits.
The large family of flavanols or flavan-3-ols—which includes catechins, epicatechins, and their oligomers such as those present in cocoa, have been shown to possess numerous beneficial properties.
Typical daily doses of cocoa flavanols vary from 5 to 1000 milligrams (mg) of flavanols with an average between 200–500 mg flavanols contained in different formulations, such as cocoa powder.
Other food sources include flavanol-enriched dark chocolate, cocoa bars, or others flavanol enriched products usually taken before sports performance.
Cocoa flavanol questions
The effect of cocoa flavanols on sports performance is not universally agreed upon with a 2018 review looking into its effects on cognitive function as well as exercise performance and recovery.
The review points to cocoa flavanol’s effect on vascular function, reduction of exercise-induced oxidative stress, and ability to alter fat and carbohydrate utilisation during exercise, without affecting athletic performance.
The team, which also includes researchers from the University of Padova, adds that at the brain level, cocoa flavanols, once crossed the blood-brain barrier, act by increasing the cerebral blood flow and promote cognitive functions.
Here, the researchers cite a paper from 2017, which suggests cocoa flavanol administration could enhance normal cognitive functioning and exert a protective role on cognitive performance and cardiovascular function specifically impaired by sleep loss, in healthy subjects.
The review’s author’s then comment on the intestinal microbiota’s role in cocoa flavanol efficacy adding that cocoa polyphenols undergo extensive biotransformation in the large intestine by the resident commensal bacteria.
“It is also gradually being understood that the diversity and specificity of these microorganisms are essential for polyphenol metabolism to produce small secondary metabolites that probably represent the bioactive compounds interacting with human biochemical pathways,” the team writes.
“Two main metabolites, phenyl-γ-valerolactone, and phenylvaleric acid are found in the urine after 5–10 hours from oral intake of dark chocolate or green tea.”
In summing up their findings, the team acknowledge that research on the effects of polyphenols on the human epigenome and their bidirectional interactions with microbiota are in its infancy,
but thanks to omics techniques and the combined use of a systems biology approach, it is possible today to rapidly reach a critical mass of knowledge for their targeted use also in the field of sports medicine.
“Individual network analysis comparing gene-nutrient associations and genetic polymorphisms, also taking into consideration the individual microbiota and its role in xenobiotics bioavailability,” the team writes.
“This will likely allow more precise and personalized strategies in athletes for effective nutritional regimens, phytocomplex supplementation/integration and targeted exercises.
“Within this context, that can be indicated collectively as phytonutritional epigenomics, polyphenols are likely candidates for safe and effective modulation of biological phenomena of interest for the improvement of sports performance,” the paper concludes.
Published online ahead of print: https://doi.org/10.3390/nu12051265
“Deciphering the Role of Polyphenols in Sports Performance: From Nutritional Genomics to the Gut Microbiota toward Phytonutritional Epigenomics.”
Authors: Vincenzo Sorrenti et al.