Top Parenting Myths we hear around the office

Myth: Iron Causes ConstipationThere are two likely sources for this myth. All infants will occasionally make some pellet-like stools and strain during bowel movements. While the infant is drawing his knees up to his chest, scrunching up his face and grunting, the parents are wondering what is causing this "constipation?" The association is made to the iron fortified formula because that is such a big component in the infant's diet. In fact, because an infant's abdominal musculature is relatively weak compared to their adult counterpart, this "bearing down" helps them pass stool and gas. The second source of this myth is the experience (subjective?) of adults that taking iron supplements causes them to be constipated. Hence, adult parents assume that this phenomenon would also exist in children.

In a well designed study, researchers compared infants given iron-fortified formula with those given a low-iron formula and others given cow's milk and followed symptoms of constipation over nine months. There was no increase in constipation with iron fortified formula.

What we do know is that iron is very important in preventing anemia in the first year of life. Anemia is dangerous to infants because it can cause developmental delay and even heart failure. If you are going to give formula, please do not use a "low-iron" formula! For parents wanting to switch formulas, please consult your pediatrician.

-Daniel Weissbluth

Singhal, A., R Morley, R. Abbott, S. Fairweather-Tait, T. Stephenson, and A. Lucas. 2000. Clinical Safety of iron-fortified formulas. Pediatrics 105 (3): E38.

Pizzarro, F., R. Yip, P.R. DAllman, M. Olivare, E. Hertramph, and T. Walter. 1991. Iron status with different infant feeding regmines: relevance to screening and prevention of iron deficiency. Journal of Pediatrics 118 (5): 687-92.