Quercetin may be the latest nutrient to offer hope in reducing the symptoms of Covid-19.
In a test of Covid-19 patients in Pakistan, a one-week treatment with quercetin was linked to milder symptoms and faster conversion from positive to negative tests.
Quercetin is a plant flavonol from the flavonoid group of polyphenols. It is found in many fruits, vegetables, leaves, seeds, and grains. Quercetin has a bitter flavor; however, it is still used as an additive to some foods and beverages.
Though quercetin is one of the most abundant dietary flavonoids found organically in nature, processing and heating eliminates much of the amount typically found in raw foods.
Substantial earlier research has demonstrated that quercetin provides broad-spectrum antiviral, anti-inflammatory and antioxidant properties.
Researchers in the current study noted quercetin’s long-proven benefits and acknowledged preliminary studies that had already linked the nutrient to Covid-19 benefits.
“Recently, several clinical trials have revealed treatment benefits of quercetin supplementation in patients with COVID-19, including prophylaxis, speedy clearance of the SARS-CoV-2, speedy resolution of the acute symptoms and improvement in the serum inflammatory biomarker levels,” the researchers wrote in the study introduction.
To conduct the study 100 Covid-19 patient-subjects were randomized to receive either a placebo or a quercetin supplement at the onset of testing positive for Covid-19.
The quercetin product was supplied by a known supplement manufacturer and was tested for purity before administration. Both the supplement group and the placebo group also received the same “standard Covid-19 care” that is provided to patients in Pakistan. The study was reserved to patients with “moderate” Covid symptoms.
According to an array of tests from outpatient physicians, “Quercetin use resulted in milder COVID-19 symptoms and improved the rate of testing positive to testing negative.”
After one week of treatment, 34 patients tested negative for Covid-19, compared to 12 in the control group. Twenty-six patients, compared to 12 in the control group, had their Covid-19 associated acute symptoms resolved.
Quercetin supplementation was also significantly linked to a faster reduction in serum LDH, a biomarker which suggests systemic inflammation.
“Our results, suggest the possible therapeutic role of quercetin in early-stage COVID-19, including speedy clearance of SARS-CoV-2, early resolution of the acute symptoms and modulation of the host’s hyperinflammatory response,” the researchers wrote in the study conclusion.
The study was an open-label randomized controlled clinical trial, and was conducted at the department of medicine, King Edward Medical University, Lahore, Pakistan.
While noting larger studies are needed, the authors concluded that there is a possible therapeutic role of quercetin supplementation in the early stages of mild to moderate symptomatic Covid-19.
“The present study also supports the safety of quercetin supplementation in patients with COVID-19 which has an unpredictable and complex course and hence may be used as an adjuvant alongside routine care in the management of mild to moderate symptoms of COVID-19,” the researchers wrote in the study summary.
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