I also shared that I had tested positive for COVID-19 last week as well. Fortunately, my symptoms were limited to feelings similar to “jet lag” for a few days. I am 100% now!
Many people have asked me if I had a secret weapon. And, yes, I think I did. It was a special form of quercetin…
This natural compound is one of the hottest topics right now in the medical literature because of its potential in possibly neutralizing the SARS-CoV-2 virus responsible for COVID-19. There is a high level of excitement based upon new research that I will share here. The caveat is that to achieve this possible benefit from quercetin there are some important considerations about the form and dosage.
Quercetin is perhaps the most abundant and active member of a group of pigments found in plants known as flavonoids. Quercetin is found in many fruit, especially citrus, apples, and berries, green leafy vegetables, seeds and nuts, green tea and other medicinal plants, dark chocolate, and red wine.
Quercetin exerts considerable health benefits as an important antioxidant and anti-inflammatory compound. Much of the recent research on quercetin has focused on its immune enhancing and antiviral aspects. It boosts white blood cell activity and mobilizes them to areas of infection. In human cell cultures quercetin has been shown to block the infectivity of a variety of viruses by inhibiting multiple processes in the virus life cycle. A human clinical trial in athletes showed these effects translated to quercetin reducing upper respiratory viral infections.
The excitement with quercetin as an answer to COVID-19 was initially the result of the possibility that quercetin may enhance the antiviral effects of ionic zinc. When zinc is unbound to other molecules, i.e., when it is in a free ionic state, it exerts significant action in blocking viruses from replicating. It does this action by inhibiting an enzyme produced by the virus known as replicase. This enzyme is what a virus uses in order to reproduce itself within human cells. Quercetin acts as what is known as a zinc ionophore by basically creating a channel that allows free ionic zinc to enter the infected cell and block viral replication.
The science on quercetin’s anti-coronaviral activity has evolved further showing additional specific actions useful against SARS-CoV-2.
In an excellent review titled “A role for quercetin in coronavirus disease 2019 (COVID‐19)” a group of Italian researchers make a very strong case for quercetin’s potential benefits in the prevention and treatment of COVID-19. Considerable attention was devoted to the multiple target sites of quercetin against SARS‐CoV‐2. Specifically, how quercetin is able to neutralize this coronavirus through detailed molecular docking studies and cell culture experiments.
One of the key aspects of the infectivity of SARS‐CoV‐2 is the presence of specialized proteins that allow it to bind to and then penetrate host cells to cause infection. If you have seen the illustration of what SARS‐CoV‐2 looks like you know that it is characterized structurally by the presence of “spikes.” These spikes contain proteins that attach themselves to a type of receptor on the surface of human cells called an ACE-2 receptor. This site acts as a doorway to infection with this virus.
Quercetin exerts significant inhibition on the binding of specific spike proteins to ACE-2 receptors, thereby blocking the ability of the virus to infect human cells. Quercetin has also been shown to directly neutralize viral proteins the are critical in the replication of SARS‐CoV‐2. It exerts multiple sites of inhibition of the virus.
The authors concluded that based upon the current data, quercetin is one of the most promising antiviral compounds capable of interfering the ability of SARS‐CoV‐2 to infect cells as well as its replication.