Submitted to: Journal of Pediatric Gastroenterology and Nutrition
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/5/2009
Publication Date: 5/14/2010
Citation: Balay, K.S., Hawthorne, K.M., Hicks, P.D., Griffin, I.J., Chen, Z., Westerman, M., Abrams, S.A. 2010. Orange but not apple juice enhances ferrous fumarate absorption in small children. Journal of Pediatric Gastroenterology and Nutrition. 50(5):545-550. Interpretive Summary: Iron is important for children to prevent anemia. Recently a type of iron called ferrous fumarate has been used more commonly to add to food. We wanted to know if vitamin C (ascorbic acid) would help small children in the United States absorb more of the ferrous fumarate. We conducted a stable isotope study and measured iron absorption before and after giving ferrous fumarate to a group of 21 children from 4 to 8 years of age. The children consumed the ferrous fumarate with and without a vitamin C source. We found that there was a benefit of the vitamin C in the orange juice to improve iron absorption, but that this benefit appeared mostly to occur in the children over age 6. This study will help us decide when to recommend giving juices like orange juice along with foods that contain iron in the form of ferrous fumarate.
Technical Abstract: Ferrous fumarate is a common, inexpensive iron form increasingly used instead of ferrous sulfate as a food iron supplement. However, few data exist as to whether juices enhance iron absorption from ferrous fumarate. We studied 21 children, ages 4.0 to 7.9 years using a randomized crossover design. Subjects consumed a small meal including a muffin containing 4 mg 57Fe as ferrous fumarate and either apple (no ascorbic acid) or orange juice (25 mg ascorbic acid). They were separately given a reference dose of 58Fe (ferrous sulfate) with ascorbic acid. Iron absorption increased from 5.5 +/- 0.7% to 8.2 +/- 1.2%, P<0.001 from the muffins given with orange juice compared with muffins given with apple juice. The absorption of ferrous fumarate given with orange juice and enhancement of absorption by the presence of juice were significantly positively related to height, weight, and age, (P<0.01 for each). Although iron absorption from ferrous fumarate given with apple juice was significantly inversely associated with the (log transformed) serum ferritin, the difference in absorption between juice types was not (P>0.9). These data demonstrate an overall benefit to iron absorption from ferrous fumarate provided with orange juice. The effect was age related such that in children >6 years of age, there was a nearly 2-fold increase in iron absorption from ferrous fumarate given with orange juice.