"Quercetin (Qu) and its derivatives are naturally occurring phytochemicals with promising bioactive effects. The antidiabetic, anti-inflammatory, antioxidant, antimicrobial, anti-Alzheimer's, antiarthritic, cardiovascular, and wound-healing effects of Qu have been extensively investigated…" ACS Omega Journal, May 2020.
Researchers have been excited about Quercetin for decades. There are a variety of research streams underway (everything from bone health and arthritis comfort to liver support, insulin regulation, pancreatic support, ovarian support, breast tissue support, allergy support, and anti-parasitic protection), but for this article, we'll focus on immune health.
Even though Quercetin is a powerhouse nutrient, it has suffered from one major drawback: this natural compound doesn't dissolve well. When Quercetin supplements are taken orally, they show disappointing absorption levels. Luckily that's about to change!
But first, let's talk about what Quercetin is.
No – Flav-o-nol!
Quercetin is a flavanol. If you've purchased a good high-quality vitamin C supplement, you may have noticed that it contains "bioflavonoids." Flavonols are simply a subclass of flavonoids that come from plants (phytonutrients).
Flavanols are found in onions, leeks, Brussels sprouts, tea, berries, beans, and apples and have a wide range of health benefits. Quercetin is a particular flavonol that acts as an antihistamine. Allergy sufferers looking for a natural, non-drowsy solution to hay fever and hives have used Quercetin for years. Histamines are part of the inflammatory response of our immune system to protect us against pathogens.
One of the most researched benefits of Quercetin is its ability to stabilize mast cells. Mast cells are a type of white blood cell found in connective tissue throughout the body. Mast cells are found in our skin, around our blood vessels, in the lymphatic system, as well as in our nerves, lungs, and intestinal tract. They are also part of our allergy response; they release histamine granules and trigger an inflammatory response to protect our bodies.
Not only is Quercetin an antihistamine and anti-inflammatory, but it's also an antioxidant. Exposure to oxygen makes our cells oxidize (like rusting from the inside out). This is normal and cleared by our lymphatic system when our bodies are in balance.
If our bodies become unbalanced or if we have an overload of free radicals (particles with unbound oxygen that cause damage to cells), our cellular structures start to degrade. In fact, this is one of the theories about why and how we age.
When it comes to viruses, there have been exciting discoveries about Quercetin in the past twenty years. Researchers have found that Quercetin has antiviral effects against RNA viruses like flu and coronaviruses and DNA viruses like the herpes family. Scientists believe Quercetin stops a virus' ability to replicate while simultaneously ensuring that the immune system does not overreact by modulating mast cells and their release of histamine.
I Get By With A Little Help From My Friends
Quercetin alone is an excellent resource for immune system priming, but it becomes even more powerful when combined with other nutrients.
We are all familiar with the power of Zinc to reduce or stop respiratory infections. But, many people don't realize that Zinc isn't just a nice-to-have; it is crucial to immune system function. This slightly brittle metal is an essential mineral that helps with growth and DNA synthesis. We do not need a lot of Zinc for our bodies to function properly, but our bodies cannot make it, so we must get it from outside sources. Unfortunately, many foods high in Zinc aren't very popular (onions, broccoli, beans.) But, Zinc plays a role in cell growth and multiplication – a necessity for our immune system's defensive response. In the lab, Zinc has been shown to shut down viral reproduction in minutes! And, Zinc is required for almost 100 enzymes to carry out their necessary chemical reactions in our bodies.
It's noteworthy that when Zinc is present in the intercellular matrix (the "water" within the cell), it increases the pH of the cell and decreases the ability of RNA viruses to replicate. Paired with Quercetin's natural RNA virus-fighting abilities, research has shown that Quercetin and Zinc can stop a virus from reproducing.
The challenge, however, is getting Zinc into our cells. It needs an ionophore to be transported across the cell wall into the center of a cell where viruses replicate. Zinc is a positively charged ion that makes it difficult for it to cross the cell membrane. An ionophore is a fat-soluble molecule that binds to ions. This allows them to move across the cell's protective cell wall. Zinc cannot get to the center of the cell without the right ionophore; it just gets stuck in the bloodstream and can't be used by the cells.
Luckily enough, the perfect ionophore partner for Zinc is…Quercetin!
Quercetin pushes Zinc into the center of the cell, where it can stop a virus from reproducing. Getting Zinc into our cells is especially important when we are sick. Zinc is part of our immune response; without adequate elemental Zinc, we can quickly become depleted. Without enough Zinc, we'll experience excess inflammation (the precursor to systemic breakdown), unbalanced oxidative stress/cellular damage, extreme fatigue, loss of appetite, and impaired wound healing. Zinc depletion can be a problem for older adults and is an underlying reason why they succumb to lowered immune responses and diseases at a higher rate than younger people.
At any age, Zinc is crucial for the growth of and normal functioning of immune cells. Even a moderate deficiency will slow down the activity of lymphocytes, neutrophils, and macrophages working to protect us from viruses and bacteria. Combining Zinc and Quercetin is the optimal solution to getting Zinc into cells, so we have the protection we need.
It Takes Three
Quercetin's transporter abilities are integral to the immune system's fight against disease, but there is one problem. To get Quercetin into the body where it can pair up with Zinc, it needs some help.
Quercetin is not water-soluble, so it is very poorly absorbed during digestion. It is an aglycone meaning it is missing a sugar that would improve its bioavailability. Under the microscope, Quercetin is a brilliant citron yellow needle-shaped crystal...but it is insoluble in cold water and only slightly soluble in hot water. However, it becomes very soluble in lipids – more on that in moment.
When Quercetin is combined with Ascorbic Acid (vitamin C), they share antiviral and immune system modulating capabilities. Ascorbic acid can also recycle Quercetin, making it even more effective and long-lasting. Vitamin C has long been recognized as an essential vitamin for fighting off sickness, its antiviral properties, protection against stress, and keeping our bodies healthy overall. By combining vitamin c and Quercetin, we can prime the immune system to be ready to fight viruses and to keep on fighting.
Vitamin C, Quercetin, and Zinc form a three-way partnership of virus-fighting immune resources. We want our bodies to have ample stores of these three nutrients before we are sick and act as a powerhouse defense working for us if we do get sick. But don't forget, we have that one missing component…
50X Your Virus Fighting Ability
Quercetin, either by itself or combined with vitamin C, reduces the oxidative damage caused by glutathione (the master antioxidant) depletion. Zinc also needs Quercetin to cross the cell wall to do its virus-fighting job. These nutrients must be as bioavailable to our body as possible, but most importantly, Quercetin has to lead the way.
A new form of Quercetin is a breakthrough! Quercetin combined with sunflower lecithin is a game-changer. It is clinically studied and has now been released for use. Called Quercetin Phytosome, it helps dramatically increase the amount of Quercetin measured in blood plasma. This new form allows high levels of Quercetin to easily cross the gut barrier and the cell wall. It still has the same ionophore capabilities to transport Zinc into the cells. It also provides significantly more Quercetin for Ascorbic Acid to recycle for even longer-lasting availability.
Doctors Michel Chrétien and Majambu Mbikay are researchers at the Montreal Clinical Research Institute (IRCM). They began studying Quercetin in the 1990s for cholesterol regulation. They saw that it was helping people with a cholesterol mutation who were also more susceptible to malaria. Soon they began researching Quercetin's effects on parasites, bacteria, and viruses.
They found that Quercetin can shut down the early entrance of viruses into cells. They have applied their research to Ebola and Zika and now to COVID-19. Chretien says, "A cell has a lock, and the virus has a key [to enter and infect the cell], but Quercetin puts glue in the lock."
Now with this new lipid-based Quercetin, we can put more "glue" in those locks! In fact, the latest form of Quercetin Phytosome is like putting SUPER Glue in those locks. It increases serum levels of Quercetin circulating in the body, gives vitamin C more to recycle, and ups the amount of Zinc that can be transported into the cells.
This trio's antiviral, antibacterial, and anti-parasitic capabilities make each of them a go-to resource for health on their own. But, using Quercetin in this new form with its enhanced bioavailability creates a tsunami of resources to keep your immune system in prime shape.
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Salehi, B., Machin, L., et al, Therapeutic Potential of Quercetin: New Insights and Perspectives for Human Health, ACS Omega 2020, 5, 20, 11849–11872, 2020 May 14. https://doi.org/10.1021/acsomega.0c01818
|These statements have not been evaluated by the Food & Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease.|
Lisa Moretti is a Certified Health Coach from the Institute of Integrative Nutrition (IIN), the largest nutrition school in the world. She was at the top of her cohort in 2015. She's been involved in the natural health and supplement world professionally since 1981.