Table 1

The table describes the findings, reported in studies, regarding serum zinc concentration and intracellular zinc concentration related to the risk factors for COVID–19 (including age, type 2 diabetes and obesity), antihypertensive agents as well as statin therapy

Type of studyn=no of subjects
N=no of studies		Serum zinc concentrationIntracellular zinc concentration
Increasing age
 Observational45n=853↓ in 31% of subjects–
 Review8N=20↓ significant with increasing age↓ significant in 1 study
 Observational17n=1521↓ significant with increasing age–
Type 2 diabetes**
 Observational22n=82↓ related to higher glycated hemoglobin↓ related to higher glycated haemoglobin
 Meta–analysis18n=20183↓ significant versus control groups–
 Cross–sectional21n=33↓ in 77 % of the subjects–
 Observational19n=31↓ in 27% versus control group (n=31)–
 Cross–sectional20n=252↓ in 68% versus control group 6.4% (n=188)–
Obesity
 Observational23
 		n=115↓ in 74% of subjects seeking bariatric surgery–
 Review23N=3↓ in 28% before bariatric surgery–
↓ in 36–51% postbariatric surgery
Diuretics
 Clinical Trial46Clopamide 5 mg/day, 16 weeks (n=8)↓ significant versus baseline↑ in WBC, ↓ in RBC
 Clinical Trial47Hydrochlorothiazide 25–50 mg /day,
6 months (n=39)		↓ significant in 51% of treatment group–
 Clinical Trial48Hydrochlorothiazide, 25 mg, ≥3 months (n=9)↔ versus controls–
 Clinical Trial*25Indapamide (n=29), Torasemide (n=5), Spironolacton (n=2), 3 months↓ significant compared with baseline zinc level↓ significant compared with baseline
ACE–inhibitors
 Clinical Trial49Captopril, 266±34 mg/day,
>6 months (n=11)		↓ significant versus baseline–
 Clinical Trial50Captopril, 75 mg/day, >3 months (n=6)↔ versus other groups↓ significant versus baseline
 Clinical Trial†28Captopril, 50–150 mg/day, 6 months, (n=10)↓ significant versus baseline↔ versus baseline
 Clinical Trial51Captopril, 6 months (n=16)‡↔ versus baseline↓ significant versus baseline
 Clinical Trial51Enalapril, 6 months (n=18)‡↔ versus baseline↓ significant versus baseline
 Clinical Trial50Enalapril, 20 mg/day, >3 months (n=7)↔ versus controls↔ versus controls
 Clinical Trial†28Verapamil, 240 mg⁄day, 6 months (n=10)↓ significant versus baseline↔ versus baseline
 Clinical Trial27Ramipril, 5 mg/day, 3 months (n=20)–↓ significant versus baseline
 Clinical Trial*25Perindopril (n=9), Captopril (n=3), Ramipril (n=2), 3 months↓ versus baseline↔ versus baseline
Calcium–antagonists
 Clinical Trial*25Amlodipine (n=13), Nifedipine (n=5),
3 months		↔ versus baseline↓ significant versus baseline
 Clinical Trial27Amlodipine, 10 mg/day, 3 months (n=20)–↔ versus baseline
Angiotensin 2 receptor blockers
 Clinical Trial27Valsartan, 80 mg/day, 3 months (n=20)↓ significant versus baseline↓ significant versus baseline
 Clinical Trial‡52Losartan, 50 mg/day, 4 weeks (n=17)↓ non–significant versus baseline↔ versus baseline
 Clinical Trial*25Losartan (n=8), Valsartan (n=2), Telmisartan (n=2), 3 months↔ versus baseline↔ versus baseline
Beta blockers
 Clinical Trial27Metoprolol, 100 mg/day, 3 months (n=22)↔ versus baseline↔ versus baseline
 Clinical Trial†28Atenolol, 50–150 mg/day,
6 months (n=10)		↓ significant versus baseline↔ versus baseline
 Clinical Trial*25Bisoprolol (n=7), Metoprolol (n=7), Nebivolol (n=4)↔ versus baseline↔ versus baseline
Statin therapy
 Review29Statin therapy, various large scale studies N = 2910–45% increased relative risk for type II diabetes (see above:**)–
 Clinical Trial31Simvastatin (n=11), Atorvastatin (n=9),
10 mg/day, 4 months		↓ significant versus baseline–
 Clinical Trial30Fluvastatin (n=20), 80 mg/day,
8 weeks		↓ significant versus baseline–

  • ↓ decreased, ↑ increased, ↔ no change, – unreported data.

  • *Randomised clinical trial, dietary zinc intake controlled,

  • †Modified diet to improve lipid profile during test–period.

  • ‡Dietary zinc intake monitored during test–period.

  • RBC, red blood cells; WBC, white blood cells.