The Contribution of Iron and Transition Metal Micronutrients to Diabetes and Metabolic Disease
Macronutrient excess is the largest single risk factor for type 2 diabetes mellitus (T2DM). Micronutrients also play essential roles in metabolism, however, and emerging data suggest that, within the broad range of average intake for these entities, much narrower optimal levels exist for various cellular functions. This is true for vitamins, minerals, and trace elements, although this chapter will focus on the transition metals, and in particular those with a developed literature relating to diabetes, notably iron, zinc, manganese, copper, and chromium. Surveys of individuals in China reveal diabetes risk is associated with all of these, as well as other metals such as arsenic, 282cesium, and strontium, some of which may be assumed to be acting as toxins rather than reflecting imbalance of necessary trace elements . We will focus on and begin with a consideration of iron, because of its long historic connection with diabetes in the context of hereditary hemochromatosis, the substantial literature, and the potential significance to the largest numbers of those with diabetes.