Studies Find Increased Anemia Risk in Babies Born to Obese Moms
Iron-deficiency anemia is still a concern for small children – it is the most common nutritional deficiency in the world, especially for those younger than the age of three years. A critical period for iron storage for the infant occurs during the last trimester of pregnancy. Studies show that babies born to obese mothers are at greater risk for low iron stores than those born to normal weight moms.
Iron is an essential mineral for good health because it helps to carry oxygen throughout the body. Iron is used to make hemoglobin and without enough, production of red blood cells (RBCs) is affected. Although interventions such as iron-fortified formulas have decreased the incidence of iron-deficiency anemia in children, the Centers for Disease Control and Prevention report that it still affects about 7% of US toddlers between the ages of 1 and 2 years.
In addition to the proper functioning of RBCs, iron plays a crucial role in the formation of the central nervous system and children born with iron deficiency are at greater risk for delays in motor and cognitive development. Fifty percent of the iron needed for infant growth is obtained before birth.
Researchers at the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University and The Mother Infant Research Institute at Tufts Medical Center have found that babies born to obese mothers – those with a body mass index (BMI) of 30 or greater – were at an increased risk for having low iron status at birth.
It is known that obesity-related inflammation hinders the transport of iron through the intestine. When a woman is pregnant, this in turn affects the amount of iron that is transferred to the placenta. But prior to now, researchers weren’t exactly sure of the reasons why this occurs.
Senior author Simin Nikbin Meydani DVM PhD and first author and doctoral student Maria Carlota Dao have discovered that levels of a hormone known as hepcidin in the mother was associated with iron status in the infant at birth. This hormone is key to keeping iron levels balanced. Excess amounts of hepcidin in a cell binds and inhibits the function of ferroportin, a protein that allows iron to pass through the cell membrane and into the bloodstream. Obese women are known to produce higher levels of the hormone.
“The chronic low-grade inflammation that can result from being obese triggers an abnormal immune response, increasing production of proteins that increase hepcidin levels,” adds Dao.
The American Congress of Obstetricians and Gynecologists recommend that pregnant women receive 27 milligrams of iron per day. Most prenatal vitamin supplements contain this amount. Iron-rich foods include lean meats, egg yolks, broccoli, spinach, dried peas and beans, raisins, and whole-grain bread.
In addition, women who are obese prior to pregnancy should aim for the appropriate weight gain goals during pregnancy as recommended by the American Pregnancy Association. Women with a BMI of 30 or greater should aim for a weight gain of 11 to 20 pounds unless otherwise directed by a physician.
Dao MC, Sen S, Iyer C, Klebenov D, and Meydani SN. “Obesity During Pregnancy and Fetal Iron Status: Is Hepcidin the Link?” Journal of Perinatology advance online publication. June 21, 2012; doi: 10.1038/jp.2012.81.
American Academy of Pediatrics (2011, April 30). Maternal obesity puts infants at risk of iron deficiency. ScienceDaily. Retrieved July 10, 2012, from http://www.sciencedaily.com-/releases/2011/04/110430133125.htm