Iron deficiency-related anemia is the most common nutritional deficiency disorder in the world, mainly affecting children, women and older adults in underdeveloped countries.To combat iron deficiency, inorganic forms of iron (such as ferrous sulfate) are used as iron supplements. However, providing large doses of this iron produces negative health effects, including diarrhea, changes in the bacteria in the gut and increased inflammation. In this study, we are comparing participants consuming the form of iron commonly used in iron supplements (ferrous sulfate) versus participants consuming other forms of iron in order to determine the effects of these iron supplements on intestinal health, immune function and iron status. The findings from this research study are important because they will inform the development of safer treatments for iron deficiency.
- Women must be >1 year post-menopausal, or had both ovaries removed if premenopausal
- BMI between 18 and 35 kg/m2
- Free of any known chronic disease
- Taking iron supplements
- Irregular bowel movements (<3 times per week)
The study is conducted at the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University. Participants will be asked to take an iron supplement, with or without a multivitamin, or placebo every day, or once a week, for 4 weeks. In addition to a screening visit before the start of the study to determine eligibility, participants will attend approximately three visits over a period of about 4 weeks. At the start of the study, participants will attend an enrollment visit (visit 1) and a baseline (visit 2), then after 4 weeks will attend a final study visit (visit 3). For visits 2 and 3, blood will be drawn twice, before and after a meal, ranging in amount for a total of 153 mL (about 31 teaspoons) per visit. A stool sample will also be collected at visits 2 and 3, and questionniares will be completed during the study visits and throughout the study on the telephone.