It is acknowledged that an impaired nutritional status increases the susceptibility and the severity of infections. In turn, serious or repeated infections increase the risk of malnutrition, by inducing anorexia with associated decreased intake of nutrients, causing a status of malabsorption, or altering the body’s metabolism and increasing demand for nutrients [14]. Therefore, it is essential to maintain adequate amounts of each micronutrient. A well-balanced diet is crucial to achieve an optimal intake of all these vitamins and essential elements. However, in the general population and also in developed countries, it can be difficult to obtain an adequate micronutrient intake versus the Recommended Daily Allowance (RDA), because of reduced intake, increased requirements for metabolism, and increased loss.