A single-blind study of the potential of zinc supplementation to decrease the risk for contracting COVID-19 was conducted in two clinics in south Florida. After exclusions and dropouts, 104 participants from a clinic that routinely prescribes zinc for COVID prevention were paired with 96 participants from a second clinic who were not routinely prescribed zinc. For ethical reasons, participants in the latter clinic who wanted to participate in the zinc group could do so. Participants were ages 50-84; exclusion criteria included current infection or antibodies indicating a previous COVID infection.
The study began on August 3, 2020, and ended on January 15, 2021 – for the most part prior to the availability of a vaccine. Patients in the non-zinc group were matched for demographics, presence of co-morbidities, and serum vitamin D level. Because of the demographics of the community involved, 90 percent of the participants were Hispanic. Although the participants knew whether or not they were taking zinc, those in the zinc group were randomly assigned to 10 mg (n=31), 25 mg (n=41), or 50 mg (n=32) of elemental zinc (as picolinate) daily and were blinded as to the dose they were taking.
Zinc supplementation resulted in significantly fewer COVID infections compared to the no-zinc group, even though the treatment group participants were an average of three years older and had 15-percent more participants who had COPD. Two participants (1.92%) in the zinc group had symptomatic COVID infections compared to nine participants (10.42%) in the no-zinc group. The two in the zinc group had mild symptoms managed via out-patient telemedicine consult. In addition, antibody tests at the study’s end showed none of the other participants in the zinc group had had asymptomatic COVID. Of the nine COVID cases in the no-zinc group, three required hospitalization for severe hypoxia and one of them died. There were no significant differences in zinc dosing, with no cases in the 10-mg daily group and one each in the 25- and 50-mg daily groups. This study adds to the growing body of evidence for using zinc as a prophylactic in COVID-19.
Reprinted from Thorne’s January 2022 “Research Extracts”
Contributed by Kathi Head, ND