Dietary vitamins modified the association of dietary iron with type 2 diabetes:the National Health and Nutrition Examination Survey,2003-2014

To the Editor:The epidemic of diabetes mellitus poses a major public health threat worldwide.In the United States,the prevalence of type 2 diabetes(T2D)affected 13.9%of adults and would continually increase.[1]Diet is one of the major lifestyle risk factors for T2D,in which dietary iron has generated substantial interest over the past 20 years.[2,3]It is to be noted that dietary vitamins A,B2,B6,E,C,and folic acid were reported to affect the absorption or oxidation of iron in body.[4]However,whether these dietary vitamins play a role in iron-related T2D remains unclear.Further research revealing the holistic role of these dietary vitamins in the association between iron and T2D is needed,which would provide important guidance for decreasing the risk of iron-related T2D.The present study aimed to examine the association between dietary iron and T2D in the National Health and Nutrition Examination Survey(NHANES)and evaluate whether holistic dietary vitamins affect this relationship.