Table 1.

Equations of search for articles used in the review and total of articles obtained.

Nutrient	Search terms	Records identified through Pubmed Search and Google Scholar	Included records
Vitamin C	("vitamin C" OR "ascorbic acid") AND ("COVID 19" OR "COVID- 19" OR "COVID- 19 Virus Disease" OR "Coronavirus Disease 2019" OR "SARS-CoV-2 Virus" OR "Severe Acute Respiratory Syndrome Coronavirus 2" OR "2019-nCoV")	n = 214	n = 13
Vitamin D	("Vitamin D" OR "Cholecalciferol" OR "Hydroxycholecalciferols" OR "Ergocalciferols" OR "25-Hydroxyvitamin D2" OR "Vitamin D3" OR "Calciferols" OR "Ergocalciferol" OR "Vitamin D2") AND ("COVID 19" OR "COVID- 19" OR "COVID- 19 Virus Disease" OR "Coronavirus Disease 2019" OR "SARS-CoV-2 Virus" OR "Severe Acute Respiratory Syndrome Coronavirus 2" OR "2019-nCoV")	n = 539	n = 51
Zinc	(“Zinc”) AND (“COVID-19” OR “Coronavirus Disease 2019” OR “SARS-Cov-2 Virus” OR “Severe Acute Respiratory Syndrome Coronavirus 2”)	n = 393	n = 16
Selenium	(“selenium” OR “Compounds, Selenium” OR “Selenic Acid” OR “Selenious Acid” OR “Sodium Selenite”) AND ("COVID 19" OR "COVID- 19" OR "COVID- 19 Virus Disease" OR "Coronavirus Disease 2019" OR "SARS-CoV-2 Virus" OR "Severe Acute Respiratory Syndrome Coronavirus 2" OR "2019-nCoV")	n = 66	n = 5