Getting to Know Quercetin and Nettles

What You Will Learn in This Article

  • What is Quercetin?
  • Importance of Quercetin for Novel Virus
  • What are Nettles?
  • Importance of Nettles for Novel Virus
  • Other Benefits of Quercetin and Nettles
  • What I Recommend

I want to share with you a new supplement we have just rolled out which may be timely given all the craziness happening around the world. As I’m writing this, California, Colorado and Oregon are on fire. Things are half-open (even if that) due to the pandemic. Parents struggle to work while having their kids at home 24/7. Compounded with not being able to go out, it’s a new way of living.

There are a few things you can do in this time to ease the impact on your body. Supporting your body’s detoxification pathways is vital during this time. The smoke can suppress your immune system and make you more susceptible to contracting the virus.

Quercetin and nettles are one quick and easy thing you can add to your protocol.

What is Quercetin?

Quercetin is a bioflavonoid found in fruits, vegetables, nuts, seeds, red wine, etc. Foods that are a good source of quercetin include capers, onions, cooked asparagus, cherries, tomatoes, red apples, berries, green or black tea, and more. Capers are the best source, while tea is on the lowest end.

However, the way the food is grown seems to make a difference in how much quercetin it provides. Tomatoes that were organically grown were 79% higher in quercetin than conventionally grown ones.

Because quercetin is poorly absorbed, it’s often combined with other compounds like enzymes, herbs high in vitamin C, or other bioflavonoids.

Importance of Quercetin Now, During the Pandemic and Fires

Quercetin has many beneficial characteristics: it improves lung function, decreases inflammation, increases antioxidants, and generally enhances immune function. Quercetin may even help heal a compromised gut barrier, or “leaky gut.”

Lung Function

Quercetin has specifically been studied for a condition called idiopathic pulmonary fibrosis (IPF). “Idiopathic” refers to an unknown cause. According to the National Institutes of Health, symptoms of this condition include shortness of breath and dry cough. Symptoms may be different between people and may develop slowly or quickly. When IPF develops into an acute situation, this condition can lead to severe oxygen deprivation which requires a ventilator.

According to a 2018 study published in Critical Care, Acute exacerbation of IPF, referred to as AE-IPF, “shares several pathophysiological features with acute respiratory distress syndrome (ARDS), a very severe condition commonly treated in this setting.” ARDS is usually the cause of death in people who die of the novel virus.

The researchers mention that the known increased risk of ARDS death due to ventilator-induced lung injury has been a helpful lesson in advising care for IPF patients. This has been reflected with the novel virus, as 80% of people who have been put on ventilators for the novel coronavirus in New York have died.

Researchers in Montreal are excited about quercetin as a possible treatment for COVID-19.

According to a 2017 study, IPF patients have been found to have significantly lower antioxidant levels in their bodies, including the master antioxidant, glutathione. They also have increased lung inflammation.

According to that same study, quercetin is able to increase internally-produced antioxidants and decrease inflammation in the blood of patients with Idiopathic Pulmonary Fibrosis, which is very similar to ARDS.


Quercetin has been found to work as a COX-2 inhibitor. Drug versions of COX-2 inhibitors include NSAIDS like aspirin and ibuprofen. Other natural COX-2 inhibitors you might be familiar with include things like green tea and curcumin. All these substances are common “go-to”s for inflammatory conditions.


Quercetin has shown antioxidant capabilities in cell studies by reducing oxidative stress and increasing Nrf2, a protein that helps protect cells and tissues from damaging free radicals.

A paper published in 2019 found a “Role of Nrf2 and its activators in respiratory diseases.” Nrf2 is important for airway health, and when it is low, patients are more likely to develop things like respiratory infections, asthma, COPD, lung cancer, idiopathic pulmonary fibrosis (IPF), and acute respiratory distress syndrome (ARDS).

Antiviral + Immune Defense

In a cell study published in the journal Viruses in 2016, Quercetin was found to be preventative against the Influenza A virus. Quercetin was able to prevent the virus from entering the cell.

Quercetin is generally supportive of the immune system. It’s been shown to stimulate the immune system, fight viruses, inhibit release of histamine, decrease inflammation, and improve the Th1/Th2 balance, so that the immune system is neither underactive or overactive. For that reason, it’s been proven helpful for asthma, allergies, and anaphylactic reactions.

Researchers in Montreal are excited about quercetin as a possible treatment for the novel virus. Since it’s already proven to be effective against Zika virus and Ebola, there’s a good possibility quercetin could also help people fighting the novel coronavirus. Because it inhibits viral entry into cells, quercetin may prove to be a great preventative and treatment strategy. Clinical trials are underway in China as of early 2020.

What are Nettles?

Nettles (Urtica dioica L.), also referred to as “stinging nettles” are leaves or stems (sometimes roots) from a bush that grows in forests, along roads, or by rivers or streams in the Northern Hemisphere. It’s referred to as “stinging” because the fine hairs that grow on the stems and leaves cause inflammation to the skin that feels like burning. A temporary rash may follow.

Blending raw nettles or cooking deactivates these “stinging” compounds and allows us to eat them and benefit from their nutrients and therapeutic effects.

Importance of Nettles Now, during Pandemic

Nettles are a great herb to add to your health regimen right now, as it is an excellent tonic for both the lungs and the immune system.

Lung Function

Nettles were studied in an animal model of asthma to determine how it could help airway inflammation. Nettles were able to decrease inflammation and protect the lungs against damage from oxidative stress.

Blood Pressure

Adults were more likely to be admitted to the hospital for the novel virus if they had pre-existing health conditions. What are those pre-existing conditions? The top 5 are in descending order: #5) cardiovascular disease, #4) chronic lung disease (COPD & Asthma), #3) chronic metabolic disease (diabetes), #2) obesity… and the #1 cause? High blood pressure.

Stinging nettle, it turns out, has traditionally been used for hypertension (high blood pressure). In an animal study, nettle leaf increased antioxidant power, decreased oxidative stress, and lowered high blood pressure.

Nettles are a good source of the antioxidant vitamin C. Vitamin C is known to be a potent water-soluble antioxidant that can prevent damage to the tissues of the body. It acts as an antioxidant for the immune system, protecting cells from infection-induced oxidative stress.


Some of the anti-inflammatory compounds in nettles include kaempferol, quinic acid, and choline. The flavonol kaempferol has been described as a potent anti-inflammatory. Quinic acid is effective in treating atherosclerosis due to its ability to lower inflammation in the blood vessels. In the Nurses’ Health Study, those whose diets were richest in choline (associated with a Mediterranean Diet) had better blood levels of inflammation markers, including C-Reactive Protein.

Nettles’ anti-inflammatory ability is also reflected in the herb’s effectiveness for pain relief. In a 27-person study of arthritis, a stinging nettle cream was very effective for pain compared to a placebo. In a randomized double-blind study of 81 patients with osteoarthritis, a supplement containing nettles improved symptoms and decreased the need for NSAIDs and other pain meds.


Nettles are a good source of the antioxidant vitamin C. Vitamin C is known to be a potent water-soluble antioxidant that can prevent damage to the tissues of the body. It acts as an antioxidant for the immune system, protecting cells from infection-induced oxidative stress.

Antiviral + Immune Defense

Nettles work as an anti-viral and to support immune defense in a few different ways:

Nettles activate CD8+ T cells (cytotoxic T lymphocytes). These CD8+ cells are very important for immune function and are important for fighting against intracellular pathogens like viruses and bacteria. It’s likely that activating them would be beneficial at both the beginning and the end of any viral infection.

Nettles are high in Vitamin C, which is essential for healthy immune function. Not only that, but it’s said to be especially helpful for respiratory infections.

You can start getting nettles into your diet by making up this Nettle Infusion. It’s super easy and very beneficial to your health. It’s important to know that, if you’re making nettle tea or heating up your nettle infusion, you shouldn’t heat it to over 140 degrees Fahrenheit (60 C), as exceeding 140 will destroy the vitamin C content. A temperature of 140 degrees is the usual temperature for your latte when you go to your favorite coffee shop.

Other Benefits of Quercetin and Nettles

Not only are nettles and quercetin great for supporting the immune system; some conditions that may be helped by this blend include:

Lowering allergy response and histamine (Both)

Quercetin may help with allergies. In a study published in Iran Journal of Allergy, Asthma, and Immunology, Italian researchers found that quercetin was as effective as an herbal Chinese formula, Food Allergy Herbal Formula (FAHF) in blocking anaphylaxis to peanuts in animal studies. They saw it as a potential allergy “drug.”

Nettles also seem to help histamine and allergies, despite containing histamine themselves. In a cell study, several compounds in nettle extract were shown to work against allergic rhinitis by fighting inflammation.

In a human study in which patients were given freeze-dried nettles for allergies, 57% said nettle was ‘effective’ and 48% said the nettle worked better than their allergy medications had.

However, unlike many over-the-counter choices to regulate histamine levels, the phytoconstituents of this plant extract do not cross the blood-brain-barrier, thus it is unlikely to cause the drowsiness or other adverse events associated with common anti-histamine OTC medications and can be taken at any time during the day.

Healing Leaky Gut (Quercetin)

Some studies indicate that quercetin could be helpful in healing a compromised gut lining, commonly referred to as “leaky gut.” It does this by improving the production of tight junction proteins which help connect intestinal cells and maintain the intestinal barrier. Quercetin has been shown in animal studies to be able to heal injuries in the intestinal lining.

Because increased permeability of the gut lining is associated with autoimmune disease, using quercetin might be helpful in addressing autoimmune conditions such as Hashimoto’s, Rheumatoid Arthritis, or Inflammatory Bowel Disease.

Blood Sugar Balance (Nettles)

Nettles may be a helpful tonic for keeping balanced blood sugar levels.

In a study of 92 patients with advanced type 2 diabetes, nettle leaf extract was given to 46 patients (one 500 mg capsule every 8 hours for 3 months) combined with the conventional oral blood sugar drugs. The placebo group did not receive the nettles. At the end of the study, the nettle group had significantly lower fasting glucose levels, 2 hour postprandial glucose (following a meal), and HbA1c levels. The researchers concluded that nettle might be a safe way to control blood sugar in type 2 diabetic patients who need insulin therapy.

What I Recommend

Here at Wellena, we have sourced a high quality Quercetin Plus Nettles supplement that is a synergistic combination of quercetin and nettles in a 1:1 ratio. The high vitamin C content of the nettle extract helps the body absorb the quercetin, and they work together to bring down inflammation and support the immune system, among other benefits, listed above.

Quercetin Plus Nettles harnesses the power of these two potent antioxidants.

Quercetin Plus Nettles harnesses the power of these two potent antioxidants.

How We Extract Constituents in Our Supplements

CO2 Extraction

Many supplements use chemical solvents to extract constituents like quercetin from their whole food sources. We use CO2 extraction, which ensures that the final product is pure and safe with no chemical residues left in the final product.


Herbal supplements like stinging nettles are standardized to ensure you’re getting a certain number of milligrams of the desired constituents. It’s a method of quality control that ensures a predetermined amount of a constituent is in the final product, regardless of the type of extraction used. That means that whether the extract is water soluble, alcohol soluble, et cetera, the supplement contains, say, 600 mg of extract, regardless of the amount of dry leaf used in making the product.

How to Incorporate Into Your Daily Regimen

How to take: As a dietary supplement, take three capsules per day with meals, or as directed by your health care practitioner.

You can try our Quercetin Plus Nettles here.




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