Quercetin for Brain Fog in Long Haul COVID

Understanding Brain Fog in Long-Haul COVID

Brain fog is a common and debilitating symptom of long-haul COVID, characterized by confusion, forgetfulness, and difficulty focusing. While its exact causes are not fully understood, one emerging theory involves zombie cells—dormant cells that fail to undergo routine programmed cell death. These cells:

• Contribute to neuroinflammation by releasing inflammatory cytokines.

• May exacerbate symptoms like mental fatigue and cognitive impairment.

Postmortem studies of individuals who died from COVID-19 show a 7-fold increase in zombie cells, making them a key focus for research. Among potential treatments, a combination of dasatinib (a cancer drug) and quercetin is being studied for its effects on these lingering cells.

What Is Quercetin?

Quercetin is a flavonoid found naturally in plants, known for its vibrant colors and protective properties. It offers a range of health benefits, making it a promising candidate for managing brain fog and other inflammatory symptoms.

Key Benefits of Quercetin:

1. Antioxidant Power:
   Neutralizes free radicals, reducing oxidative stress and preserving cellular health.

2. Anti-Inflammatory Effects:
   Modulates inflammatory pathways, helping to reduce chronic inflammation.

3. Immune Support:
   Enhances immune response and exhibits anti-histamine properties, benefiting individuals prone to allergies.

4. Heart Health:
   May lower blood pressure, improve LDL cholesterol levels, and support cardiovascular health.

5. Neuroprotection:
   Antioxidant properties contribute to potential protection against age-related cognitive decline.

6. Antiviral Properties:
   Shown to inhibit the replication of certain viruses, supporting the immune system during respiratory infections.

Food Sources of Quercetin

Incorporating quercetin-rich foods into your diet is a natural way to increase intake. The best sources include:

Vegetables:

• Onions (especially red onions).

• Asparagus.

• Broccoli.

• Green peppers.

• Peas.

Fruits:

• Tomatoes.

• Apples.

• Cherries.

• Berries (blueberries, blackberries, and raspberries).

Leafy Greens:

• Red-leaf lettuce.

Quercetin Supplementation: What You Need to Know

When dietary sources aren’t enough, quercetin supplements can help. However, understanding bioavailability is crucial to ensure effectiveness, particularly for brain fog and neuroinflammation.

Choosing the Right Quercetin Supplement:

1. Avoid Metabolites and Glycoside Forms:
   These forms are less neuroprotective and cross the blood-brain barrier less effectively. Look for supplements labeled hesperidin-methyl-chalcone (HMC) or quercetin-chalcone.

2. Opt for Enhanced Forms:
   Liposomal or phytosomal quercetin offers higher potency and better absorption.

   • Recommended product: Thorne Quercetin Phytosome (available in the FullScript store).

3. Mind the Dosage:
   General guidelines suggest taking no more than 1g per day. High-potency forms require careful dosing to avoid side effects.

4. Combine With Vitamin E:
   Taking quercetin alongside a multivitamin or with foods can improve absorption.

How Quercetin May Help Brain Fog in Long-Haul COVID

Quercetin’s ability to cross the blood-brain barrier makes it uniquely positioned to:

• Neutralize zombie cells, reducing neuroinflammatory burden.

• Improve cognitive function by reducing oxidative stress and inflammation.

• Support overall brain health, potentially alleviating symptoms of brain fog.

By targeting the root causes of inflammation, quercetin offers a multi-faceted approach to managing brain fog in long-haul COVID.

Bottom Line: Incorporating Quercetin Into Your Routine

If you’re experiencing persistent brain fog:

1. Increase your intake of quercetin-rich foods like onions, berries, and leafy greens.

2. Consider supplementing with a high-bioavailability quercetin product, such as Thorne Quercetin Phytosome.

3. Pair quercetin with a multivitamin or meal to enhance absorption and maximize its benefits.

Quercetin is a promising option for addressing brain fog in long-haul COVID, combining its antioxidant, anti-inflammatory, and neuroprotective effects to support mental clarity and overall health.

References 

Costa LG, Garrick JM, Roquè PJ, Pellacani C. Mechanisms of Neuroprotection by Quercetin: Counteracting Oxidative Stress and More. Oxid Med Cell Longev. 2016;2016:2986796. doi:10.1155/2016/2986796 https://www.hindawi.com/journals/omcl/2016/2986796/

McClure, Paul. Drugs identified that may reverse brain fog caused by COVID-19. New Atlas. 2023 Nov 22. https://newatlas.com/medical/four-existing-drugs-may-reverse-premature-brain-aging-covid-19/

Ossola B, Kääriäinen TM, Männistö PT. The multiple faces of quercetin in neuroprotection. Expert Opin Drug Saf. 2009;8(4):397-409. doi:10.1517/14740330903026944 https://www.tandfonline.com/doi/full/10.1517/14740330903026944