Top Quercetin Benefits for a Better Health

  • Nature's Source

What is Quercetin?

Quercetin mostly serves as a pigment for plants that belong in the flavonoid family, a form of antioxidants. It is found in many fruits such as apples and berries, vegetables such as onions and leafy greens, as well in many teas and wines. Quercetin works by scavenging particles in the body known as free radicals which damage cell membranes, interfere with DNA, and damage blood vessels. As a potent antioxidant and anti-inflammatory compound, quercetin’s health benefits include neutralizing free radicals while also supporting blood vessel integrity and the immune response.

Quercetin Health Benefits

More recently, quercetin is gaining attention due to new research findings showing the therapeutic potential of this compound, particularly in immune support. Research shows that this compound exhibits antiviral, anti-inflammatory effects. More specifically, quercetin can help mitigate lipid oxidation, clot formation, and blood vessel integrity. This means that quercetin can protect blood vessels from fatty deposits and plaque as well as promote smooth blood flow.

Allergy Support

First, quercetin can provide relief for those who suffer from allergies. Whether it's seasonal, asthma, hay fever, or hives, quercetin can help reduce symptoms by stabilizing the release of histamines from immune cells. These histamines are the chemicals responsible for allergic symptoms. Researchers think that quercetin may help reduce symptoms of allergies, including runny nose, hives, watery eyes, swelling of the face and lips. The optimal dose to reach these anti-histamine-like effects is can range from 1000-3000mg daily. In addition, combining quercetin with vitamin C and nettle leaf can maximize this antihistamine effect, adding more antihistamine machinery. Consulting with a naturopathic doctor can help you find the optimal dose for your allergy symptoms.


Quercetin’s antiviral properties have been investigated in numerous studies. More recently, research shows that quercetin and its derivatives could interact with specific proteases essential for viral replication, such as in Hepatitis, HIV, Coronaviruses, and Enterovirus. Research is showing Quercetin’s potential to block “ACE2 receptors” on cells to which COVID-119 attaches, similar to a lock and key. Studies show that quercetin can block the virus from entering and therefore hijacking the cellular machinery, it uses to replicate which may halt the virus’ chance to multiply in the early stages. Based on its molecular structure, quercetin could be a “key” that fits the lock and may block damaging keys from attaching. Quercetin along with vitamin C and Zinc seems to show a synergistic effect with halting viral replication and reducing further damage in the vasculature. This is mainly due to overlapping antiviral and immunomodulatory properties and the capacity of vitamin C to recycle quercetin, increasing its efficacy while zinc prevents the viral entry and further suppresses replication

Cardiovascular Support

Research now solidifies the link between inflammation and most diseases, particularly heart disease. Because of its ability to reduce inflammation and fight oxidative stress, quercetin seems to be beneficial for individuals with cardiovascular disorders. Quercetin supplements may help reduce the risk of plaque build-up in arteries also known as atherosclerosis, which can lead to a heart attack or stroke. Inflammation is a primary driver in these conditions and quercetin supplementation may help slow down inflammation in conditions such as high cholesterol, diabetes, eye-related disorders, cognitive impairment, and gout. Test tube studies also show that quercetin prevents oxidation to LDL cholesterol, and population studies show that people who eat diets high in flavonoids have lower cholesterol.

Who Should Not Take Quercetin?

Pregnant women, individuals with kidney disease, and cancer patients undergoing chemotherapy should avoid quercetin. It may also interact with certain drugs so it is best to consult with your primary care provider before taking quercetin. These drugs include anticoagulants such as Warfarin (Coumadin), Clopidogrel (Plavix), and Aspirin. Other interactions to note are chemotherapy drugs, corticosteroids, and digoxin.

Not All Quercetin Supplements Are the Same

Typically, quercetin is not absorbed that well. The presence of fat is key to the absorption of quercetin. The limiting factor in quercetin’s clinical efficacy appears to be its poor bioavailability. Enzymatically modified isoquercitrin (EMIQ) has been shown to have significantly greater bioavailability than other available forms. There are now forms of quercetin that are more bioavailable to optimal absorption. So, look for activated quercetin such as EMIQ as an ideal option. Taking the capsule with a meal that contains fat can further help with absorption. Great quercetin supplement options:
• Bioclinic or Natural Factors Bioactive Quercetin EMIQ 50mg: A most absorbable form of quercetin, offers 40 times greater absorption than regular quercetin
• Quercetin SAP: great option with bromelain for further anti-inflammatory effects • AOR Quercetin Pro: high dose of 500mg per capsule


Quercetin is a versatile compound that displays a broad range of therapeutic properties. It is considered one of the most abundant antioxidants in the diet. Its main effects are anti-inflammatory, anti-viral, cardiovascular support by fighting free radicals and reducing inflammation. Although is it possible to get plenty of it from a healthy plant-focused diet, some may benefit from taking this compound in a concentrated capsule form for even stronger therapeutic effects.


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