Up to 3 million more children suffer lesser but still serious effects, such as loss of night vision. Iodine deficiency is the world's leading single cause of preventable brain damage and mental retardation. Where this deficiency is endemic, the entire population may be affected, with different symptoms appearing in different age groups. The combination of malnutrition and infectious disease can be particularly pernicious. Protein-energy malnutrition can impair the immune system, leaving malnourished children less able to battle common diseases such as measles, diarrhea, respiratory infections, tuberculosis, pertussis, and malaria.
Malnutrition can also heighten the adverse impacts of toxic substances.
The consequences of food and nutrition shortfalls are enormous. In rapidly industrializing cities with high levels of malnutrition as well as disease and growing industrial pollution, residents may confront a triple burden of malnutrition, infection, and toxic pollution. References and Notes 1. Christopher J.L. Murray and Alan D. Lopez, eds. Ibid. , p.