Flavonoids show benefits against flu infections especially when a specific gut bacterium is present
Researchers from the Washington University School of Medicine, St. Louis have concluded from an animal study published in Science, that a specific microbe found in the gut may protect consumers of flavonoid-rich foods against flus.
The protection from flu was found to be the result of a metabolite produced in the gut as a result flavonoid consumption. The metabolite is called desaminotyrosine, otherwise known as DAT, according to the researchers and is produced by an obligate anaerobic bacterium from the clostridium group called Clostridium orbiscindens. Flavonoids as you may know, are a sub-group of polyphenols, and within that group are anthocyanins, which are plant pigments.
When researchers gave DAT to mice and then infected them with the flu virus, the mice experienced far less lung damage than mice not treated with DAT.
It was also observed in the study that mice treated with antibiotics had more serious flu symptoms, possibly because important gut bacteria responsible for creating DAT were killed off.
So What does DAT do?
As reported by the researchers, DAT enters the blood and triggers a signalling pathway which ultimately leads to and increases antiviral response by white blood cells.
In simplified terms, DAT fires up the immune system to fight pathogens.
The scientific evidence can´t be ignored
This study further adds to the rapidly increasing body of scientific evidence which points to the health benefits of combining polyphenolic prebiotics with probiotics.
Among the richest foods in flavonoids, are black elderberries, chokeberries and blackcurrants.
Black elderberry holds particular value as traditional remedies against upper respiratory infections and has been shown to have potent antiviral properties. Its use against coughs, colds and flus and for protection against illness goes back about 2000 years.
In 2016 a human study published in Nutrients (Tiralongo et al.) reported that participants who took an elderberry formula produced by Iprona AG had significantly less severe symptoms if they were to catch a cold. Furthermore, the participants who received the elderberry formula had significantly fewer cold episode days and about a third shorter illness duration.
In 2012, Krawitz et al. also demonstrated a potent antibacterial and antiviral effect of a standardized elderberry extract made from Haschberg elderberries in an in vitro study.
It stands to reason that combining elderberry extracts, preferably from the potent Haschberg variety with the right probiotic formulation can significantly improve the body´s ability to the fight against flu infections.
Anthocyanins like cyanidin 3-glucoside, which are flavonoids found in abundance in Haschberg elderberries, have been shown to have a prebiotic effect by increasing the population of beneficial gut bacteria like Atopobium spp., Bifidobacterium spp., Lactobacillus spp., Clostridium coccoides, Eubacterium rectale, while at the same time inhibiting the growth of harmful bacteria like Bacteroides spp. and Clostridium histolyticum (Hidalgo et al, 2012).
Including standardized Haschberg elderberry extracts in probiotic formulations is hence a classic win-win move.
Reference: DOI: 10.1126/science.aam5336