MANHATTAN, Kan.—Obese women are more likely to suffer from iron deficiency than their normal weight counterparts, according to a study published in the Obesity journal (2011 Jan;19(1):191-9. DOI:10.1038/oby.2010.112).
Researchers Florence Neymotin from Kansas State University, Manhattan, KS, and Urmimala Sen from Georgia State University, Atlanta, noted they were examining “examines a pathway to increased levels of obesity as of yet almost entirely unexplored," when they looked at the relationship between obesity and iron deficiency via analyses of blood samples. They wrote other medical studies have used cross-sectional data to concluded a negative relationship between body mass index (BMI) and iron levels, but the current study uses a much larger sample in terms of number of observations and time span, controls for a larger number of demographic characteristics.
They used public-use data files from the continuous National Health and Nutrition Examination Survey (NHANES) (1999 to 2006) survey to determine the relationship between obesity and an individual's iron blood content. Results suggest a negative relationship between levels of iron blood content in women older than 12 years old and individual BMI after controlling for other individual characteristics.
They found as iron deficiency increases by 1 percent, average BMI will correspondingly increase by about 0.10 percent on average.
However, the researchers noted the exact process by which iron levels affect an individual's BMI is still medically in question. “The current analysis has clearly established a correlational, although not a definitively causal, relationship between iron deficiency and BMI," they wrote. “A causal relationship would indicate the unambiguous benefit of iron supplementation in the population of individuals likely to develop anemia. Nevertheless, it is possible given the results of the current analysis that identification of individuals with low iron levels will serve as method of targeting those at risk of developing obesity."