Chelation is the process whereby an organic moiety acts as a ligand to bind a metal ion through two or more coordination bonds. Some low-molecular-weight compounds that may be released during the digestion of food can act as metal chelators and increase metal solubility in the intestinal lumen. In some circumstances, chelated forms of metals are naturally present in food, such as heme iron (part of hemoglobin or myoglobin protein) found in meat. Heme is a stable protoporphyrin ring-containing compound that protects a central iron atom from interacting with other potentially deleterious compounds, such as phytic acid, that would reduce its availability and inhibit iron absorption. Nonheme iron bioavail-ability is affected by various enhancing and inhibitory substances found in food. In contrast, heme iron bio-availability is not. The heme moiety is absorbed intact by the enterocyte. Inside the enterocyte a cytosolic enzyme heme oxygenase breaks apart the protopor-phyrin ring and releases the caged iron atom, which can then be transferred out into the blood.

Breaking Bulimia

Breaking Bulimia

We have all been there: turning to the refrigerator if feeling lonely or bored or indulging in seconds or thirds if strained. But if you suffer from bulimia, the from time to time urge to overeat is more like an obsession.

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