What’s All The Buzz About Quercetin?

From Brian C. Joondeph, M.D. on American Thinker.com (Nov. 2, 2021):

Quercetin has been in the news lately, particularly as one of many potential therapeutics that might have some benefit in the prevention or treatment of COVID infection. Is there anything to this?

Big media and the medical establishment are quick to pounce on any “unapproved” potential therapeutics that haven’t gone through large prospective randomized clinical trials and don’t have the seal of FDA approval. Even FDA approval is not enough if the medications are being used off-label, as in the case of hydroxychloroquine or ivermectin.  Decades ago, both were deemed safe and effective by the FDA and approved for human use, although not for COVID or similar viral infections as COVID didn’t even exist when the FDA approved these medications.

Today there is a peculiar hostility toward these medications, both of which are on the list of the World Health Organization’s essential medicines. A Fox News host told viewers that hydroxychloroquine “will kill you” and the FDA told its Twitter followers that ivermectin is for horses and cows and to stop using it. This must have been shocking news to millions around the world who take these medications, some for many years, in the U.S. prescribed by a physician, and elsewhere in the world readily available over the counter.

I am not advocating for or against these drugs, instead referring interested readers to other sources of information on the science and potential benefits of these medications in our fight against COVID. Quercetin appears to be the third in this line of potential therapeutics, not yet being called horse paste but, if history is a guide, it may soon be maligned as dog and cat medicine, something that can also be said for many drugs taken by humans but also used in animals.

What is quercetin? It’s described as “a pigment” which may lead CNN or Fox News to equate its use to drinking paint. Technically it is a flavonoid, “a group of plant metabolites thought to provide health benefits through cell signaling pathways and antioxidant effects. These molecules are found in a variety of fruits and vegetables.”

These compounds have several health benefits including reducing the risk of heart disease, cancer, and degenerative brain disorders through anti-inflammatory effects as a free radical scavenger. While present in fruits, vegetables, and green tea, it is also available as a non-prescription supplement in capsule or powder form.

Quercetin, like hydroxychloroquine and ivermectin, is a zinc ionophore, facilitating the entry of zinc into cells where it interferes with viral replication, potentially suppressing COVID infection.

Could quercetin be of benefit against COVID, or for that matter, the common cold or the flu? As are always told to “follow the science”, what does science say?

A 2012 paper published in Antiviral Research found that quercetin inhibits rhinovirus (common cold) replication both in vitro and in vivo, meaning in the laboratory and in humans. Another 2016 paper in Viruses noted that quercetin inhibited influenza A (seasonal flu) virus entry into cells. Is quercetin a cure or panacea? Certainly not as we have no cure for these viral infections. But following the science leads to the conclusion that it helps. But what about for COVID?

Following the science, rather than the FDA Twitter feed, suggests that quercetin may be of benefit in COVID. A 2021 paper in the International Journal of General Medicine, a prospective, randomized, controlled clinical trial of 152 early-stage COVID patients, the type of study always demanded by Dr. Anthony Fauci and the medical smart set, concluded, “Quercetin is a safe agent and in combination with standard care, when used in the early stage of viral infection, could aid in improving the early symptoms and help in preventing the severity of COVID-19 disease.”

The same group published in the same journal, also in 2021, a smaller similarly designed clinical study concluding, “Quercetin statistically shortens the timing of molecular test conversion from positive to negative, reducing at the same time symptoms severity and negative predictors of COVID-19.” [read more]