Review of nutritional components in Covid-19: what about micronutrients?

Nutritional status is an important protection factor against viral infections. Both undernutrition and malnutrition cause deficits in micronutrients, trace elements and vitamins necessary for various physiological functions and the appropriate functioning of the immune system. These deficiencies and infectious diseases often coexist, with complex interactions. An assessment of the micro-nutrient nutritional status of Covid-19 patients has not been at the center of priorities and recommendations, due to both the medical emergency and the absence of direct evidence and rapid effects of supplementation. Few recommendations have come from learned societies due to the lack of significant evidence of the effects of supplementation in positive patients and a need for robust studies. Essential trace elements and vitamins are necessary for the differentiation, activation and execution of many functions of immune cells, but their specific role has yet to be defined. This review article discusses in the context of Covid-19 the importance of micronutrients (selenium, copper, zinc, vitamins C, D, A and those of group B) in the host to tend towards an optimization of the immune response to infections. A nutritional balance remains the key word for achieving micronutrient homeostasis. Attention had to be paid to micronutrients in primary prevention, in the general population, in order to reduce the risk of impaired nutritional status in case of major health situations.