Increased Micronutrient Requirements during Physiologically Demanding Situations: Review of the Current Evidence

Abstract

Every day, the human body is exposed to physical and psychological challenges that upset its internal equilibrium. Strenuous activities, daily defense against pathogens or the response to infection, seasonal changes, and recurring natural biological processes (e.g., the menstrual cycle) can all disturb homeostasis. The body brings its internal environment back into balance by the constant interaction of its many regulatory processes, allowing it to adapt to the ever-changing environment. This ability to adapt and respond (referred to as ‘phenotypic flexibility) is fundamental to maintaining good health. Micronutrients (vitamins and minerals) have key roles in numerous homeostatic processes, enabling the body to produce enzymes, hormones and other substances that are essential for energy production, cell maintenance and repair, immune function and recovery from illness, blood formation, and maintenance of vital organs. Micronutrients are thus crucial to facilitate adequate responses to stressors that may challenge the body’s homeostasis. Micronutrients are generally not produced by the human body, necessitating an adequate daily intake at levels that have been recommended by various governing bodies. However, micronutrient requirements to optimally support homeostasis during daily demanding situations have not been clearly established. This review examines the roles of micronutrients during some of these demanding situations, to help determine whether there may be a rationale for increasing micronutrient intake during these periods to address any increased needs and potentially aid recovery.