NEW YORK (Reuters Health) – taking iron supplements does not take advantage of pregnant women who do not have already iron-poor blood, finds a new study.
Anemic pregnant women in West Africa strengthen their iron levels by taking supplements, but women who have had the highest for starters did not see any additional increase, according to the study in the American Journal of Clinical Nutrition.
"This is what you'd expect based on how the bowel responds to iron," said Kimberly O'Brien, Professor of human nutrition at Cornell University, who was not involved in the study. "Gut senses when you need that iron," and your body absorbs better, O'Brien told Reuters Health.
Iron is essential to make hemoglobin, a component of red blood cells that carries oxygen throughout the body. Iron In pregnancy, a woman needs rise as your body produces higher volumes of blood.
Less than one in five pregnant women in the United States have been anemic in 2005, according to the World Health Organization (who). In Africa, however, up to 57 per cent of pregnant women are anemic.
To determine how much supplemental iron was needed to bring women at levels up to a range of sound, the Belgian team of researchers and of the United States has recruited 1270 pregnant women in Burkina Faso. About 550 of them (43 percent) have been anemic at the beginning of the process.
Half of the women took supplements with 60 mg iron and 400 micrograms of folic acid. The other half took supplements with 30 milligrams of iron, the same amount of folic acid and various other nutrients including zinc and vitamins a and c both groups have taken vitamins from the moment they were enrolled in the trial until 3 months after childbirth.
The researchers found that women who have been anemic at the start of the study and those who have not been found with approximately the same levels of iron in their blood-about 11 grams per deciliter. Levels slightly above this are considered normal in pregnant women by the who.
Women who took iron and folic acid, most other nutrients had the same benefit as women who took supplements of iron and folic acid, although the latter contained twice the amount of iron. This may be because women absorb enough iron to the smallest dose, said O'Brien.
Iron during pregnancy is important because the fetus needs oxygen to develop properly (see history of Reuters Health on March 3, 2011). Low levels of maternal iron have been linked with low birth weight, which is dangerous for children, because they are more likely to have disabilities or die during the first are one year old.
Iron levels in pregnant women actually drop as the pregnancy progresses, with the requirements of the highest iron in the third quarter, said O'Brien.
U.S. Guidelines recommend that pregnant women get 27 mg of iron per day from a combination of food and supplements. Most prenatal vitamins contain at least 6 mg of iron and cost between $ 3 and $ 40 per month. Women of childbearing age typically get approximately 13.7 mg of iron per day, according to the Centers for Disease Control and Prevention.
The lead author of the study by the Institute of tropical medicine in Antwerp, Belgium, did not respond to requests for comment by the deadline.
"The benefit of iron supplements for women nonanemic is unclear", the team concludes in their book.
Women in Africa may have less iron in their diets than those in the United States, noted the O'Brien. In addition to more people there are intestinal parasites, that "hook on your intestines and feed on blood," he said.
Can "have an increased need for iron loss of blood for those pests," he explained.
When the body has sufficient levels of iron, the intestines and absorbs no more, O'Brien added. "Normally it's okay because we have enough stores, but the iron requirements of pregnancy are so high."
Source: http://bit.ly/hxQQpz The American Journal of Clinical Nutrition, March 2, 2011.
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