Poor iron status affects billions of people worldwide. The prevalence of obesity continues to rise in both developed and developing nations. An association between iron status and obesity has been described in children and adults. The mechanism explaining this relationship remains unknown; however, findings from recent reports suggest that body mass index and inflammation predict iron absorption and affect the response to iron fortification. The relationship between inflammation and iron absorption may be mediated by hepcidin, although further studies will be required to confirm this potential physiological explanation for the increased prevalence of iron deficiency in the obese.