Malnutrition and infection: Complex mechanisms and global impacts

Activation and sustenance of immune responses during infection requires increased energy consumption. Protein energy malnutrition (PEM) is a critical, yet underestimated factor in susceptibility to infection, including the “big three” infectious diseases: HIV/AIDS, tuberculosis, and malaria. In this article, we discuss current concepts and controversies surrounding the complex influences of malnutrition on infection and immunity, and point to practical consequences of countermeasures in acute malnutrition. We call for new strategies to overcome worldwide morbidity and mortality caused by chronic malnutrition in impoverished countries and by the newly emerging public health threat of overnutrition in industrialized societies