Iron deficiency may be more common than we think

How prevalent is iron deficiency among the American public? Researchers of a recent study published in JAMA sought answers and discovered that absolute and functional iron deficiency affect a large proportion of American adults even in the absence of anemia, heart failure, chronic kidney disease, or a current pregnancy.

Out of the study sample of 8,021 adult participants, an estimated 14% of U.S. adults had absolute iron deficiency, and an estimated 15% had functional iron deficiency. Absolute iron deficiency results from a severe reduction or absence of iron stores. Functional iron deficiency occurs in the presence of adequate iron stores but insufficient iron availability. Data were taken from the National Health and Nutritional Examination Survey 2017 to 2020 prepandemic cycle.

Researchers hypothesized that dietary iron intake, food security, and alcohol use would be associated with iron deficiency, but did not find clear patterns to support these nutritional factors as potential causes. Approximately 27% of participants reported marginal, low, or very low food security.

“This cross-sectional study indicates that both absolute and functional iron deficiency affect a large proportion of adults in the U.S., especially among those without conditions often screened for iron deficiency,” noted study authors. “Moreover, iron supplement use was infrequent among adults with iron deficiency. Absolute and functional iron deficiency may be a widespread, underrecognized public health problem.”

CDC recommends iron screening for high-risk groups, but there is no clear recommendation for iron deficiency surveillance in the general population.

According to the study authors, current screening recommendations may miss 70% of iron deficiency cases among children and during pregnancy—populations who are at high risk of developing iron deficiency or anemia and who are more commonly tested.

Although most research has focused on adverse outcomes among people with iron deficiency and anemia, iron deficiency affects nonerythropoietic tissue, such as skeletal and cardiac muscle, in the absence of anemia, according to the research.