The Z-Stack supplement contains 800 mg of Vitamin C (as Ascorbic Acid), 125mg of Vitamin D3 (as Cholecalciferol), 30 mg of Zinc (from 130 mg of Zinc Sulfate) and 500 mg of Quercetin.
According to a clinical study conducted by the Saudi Arabian Ministry of Health in 2020, the study reported “Quercetin is a safe natural anti-oxidant and anti-inflammatory polyphenolic compound that found in various natural sources include onion, red grapes, honey and citrus fruits. It was shown that quercetin has the ability to chelate zinc ionsand act as zinc ionophore.
Therefore, quercetin could have antiviral activity against many RNA viruses.”
This study is available for review at: https://clinicaltrials.gov/ct2/show/NCT04468139