No, there is no dietary supplement that can prevent COVID-19. But, dietary supplements can help boost our immunity, and that would help in lowering the risk of COVID-19.
In fact, it is adequate nutrition, that includes foods rich in various micronutrients, that can support the immune system. Also, maintaining a healthy weight, as well as having a healthy lifestyle which includes regular physical activity, safe exposure to sunlight, stress management and adequate amounts of sleep are all important to build up a stronger immune system. And with a stronger immune system, you will be better able to combat this pandemic.