Iron-deficiency anemia is a common problem, affecting approximately 8 percent of one- to five-year-old children in the United States. Various studies have found that iron-deficiency anemia is associated with lower test scores in mental and motor functioning in toddlers and worse school performance in adolescents. The absorption of iron can be affected by the presence of substances that enhance or inhibit iron absorption. One enhancer is ascorbic acid, which is present in some fruit drinks, such as orange and apple juice, that become a larger portion of children’s diets as they age. Apple juice has less ascorbic acid than orange juice and is consumed more than orange juice in the United States. There is some concern that apple juice may not be as good an iron-absorbing enhancer as orange juice, but few studies have evaluated this concept. Shah and colleagues assessed iron absorption in children in meals containing apple or orange juice.
The participants in the study were children three to six years of age, drawn from the general population. They were included in the study if they were within the 5th and 95th percentiles of weight-for-height, had no underlying medical problems, took no medications or vitamin supplementation, and were willing to drink apple and orange juices. The children consumed identical meals on two consecutive days, with apple juice served one day and orange juice the next in a randomized fashion. Iron absorption was measured from red blood cell iron stable isotopes 14 days later. Complete blood count, serum ferritin concentration, and transferrin receptor levels were evaluated at this time. The main outcome measurement was iron absorption assessed by established isotope methods.
A total of 21 children completed the study. The nutritional intake from the two study meals showed that the orange juice meal had significantly higher levels of absorption of protein, phosphate, zinc, copper, and ascorbic acid. The mean absorption of iron was the same for orange and apple juice meals. The iron absorption from the apple juice meal was significantly correlated with serum ferritin concentration levels, while the absorption from the orange juice meal was correlated with serum transferrin receptor concentration.
The authors conclude that children absorb iron well from meals that contain apple or orange juice. They add that current recommendations are for children to receive five servings of fruits, juices, and vegetables every day. Apple juice can be a part of their diet without any concern about iron absorption. They caution that excessive amounts of apple juice can have some negative consequences, such as abdominal pain and diarrhea.