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2019-03-07 14:01:01

By Matt Walker AN ARTIFICIAL gut could help alleviate iron deficiency in millions of people around the world. By assessing how much of the iron in a particular food would be absorbed by the intestine, the gut may help researchers develop food with more iron stored in a form the body can use. Iron deficiency is one of the world’s most widespread nutritional problems, with many researchers developing iron-rich strains of cereals to combat it ( New Scientist, 14 August, p 12). But just because food is rich in iron doesn’t necessarily mean that it is absorbed by the body. Now Raymond Glahn of the US Plant, Soil and Nutrition Laboratory in Ithaca, New York, has designed an artificial gut to test the “bioavailability” of iron in foods. Glahn’s laboratory gut consists of a series of wells about 4 centimetres across, each divided into an upper and lower chamber by an artificial membrane. Food samples are placed in the upper chamber where they are digested by natural stomach enzymes for around three hours. The lower chamber contains a culture of cells, known as Caco-2 cells, which resemble the nutrient-absorbing cells that line the inner surface of the small intestine. To gauge the uptake of iron, Glahn measures the amount of ferritin, an iron-storage protein, produced by the cells. “We have demonstrated that ferritin formation is a highly sensitive and accurate measure of iron uptake,” says Glahn. First results, announced earlier this month, showed that adding vitamin C to infant rice cereal increases the amount of available iron. But citric acid, found in larger amounts in cow’s milk than human breast milk,