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The relationship between iron status and food iron absorption was evaluated in 75 normal volunteers, 15 patients with idiopathic hemochromatosis, and 22 heterozygotes by using double extrinsic radioiron tags to label independently the nonheme and heme iron components of a hamburger meal. In normal subjects, absorption from each of these pools was inversely correlated with storage iron, as measured by the serum ferritin concentration. In patients with hemochromatosis, absorption of both forms of iron was far greater than would be predicted from the relationship between absorption and serum ferritin observed in normal volunteers. Nevertheless, there was still a modest but statistically significant reduction in absorption of nonheme iron with increasing serum ferritin. This relationship could not be demonstrated in the case of heme iron absorption. In heterozygotes, nonheme iron absorption from a hamburger meal containing no supplementary iron did not differ significantly from that observed in normal volunteers. However, when this meal was both modified to promote bioavailability and supplemented with iron, absorption of nonheme iron was significantly elevated. These studies confirm the presence of excessive nonheme iron absorption even from unfortified meals in patients with idiopathic hemochromatosis and suggest in addition that they are particularly susceptible to iron loading from diets containing a high proportion of heme iron. Impaired regulation of nonheme iron absorption was also observed in heterozygous individuals, but a statistically significant abnormality was demonstrable only when the test meal contained a large highly bioavailable iron supplement.

Traditionally the iron status of a population is assessed by estimating the prevalence of iron deficiency anemia. This approach is inadequate in countries where the diet is heavily fortified with iron because it conveys no information about the iron-replete segment of the population. In the present study iron status of a US adult population was evaluated using data collected in the second National Health and Nutrition Examination Survey (NHANES II). Body iron was estimated in each of 2,829 individuals from measurements of hemoglobin concentration, serum ferritin, transferrin saturation, and erythrocyte protoporphyrin. When individuals between 18 and 64 years of age were divided on the basis of sex and menstrual status, body iron reserves were normally distributed and averaged 309 mg in women 18 to 44 years, 608 mg in women 45 to 64 years, and 776 mg in men 18 to 64 years. The dispersion of storage iron in these groups was similar, with standard deviations of 346, 372, and 313 mg, respectively. The prevalence of iron deficiency anemia was surprisingly low, ranging from only 0.2% in adult men to 2.6% and 1.9% in pre- and postmenopausal women, respectively. Epidemiologic methods that examine iron status in the entire population assume importance in light of evidence that in certain segments of the US population, iron deficiency anemia is now less common than the homozygous state for hereditary hemochromatosis.

Iron has been recognized as a potent hematinic since the inception of hematology as a clinical discipline. Even ancient civilizations believed in the beneficial effects of medicinal iron. Nevertheless, the precise functional liabilities of iron lack remain the subject of continuing debate. The consequences of iron deficiency, particularly from a socioeconomic standpoint, are especially important in light of its high global prevalence. A recent review of the literature indicates that approximately 30% of the estimated world population of nearly 4.5 billion are anemic, and at least half of these, 500 to 600 million people, are believed to have iron deficiency anemia.

The article discusses the 2007 revisions to the Underwriters Laboratories (UL) 864 standards for fire safety. The UL 864 Ninth Edition covers four classes of change including changes that reflect consistency with the National Fire Protection Association 72 safety code, changes that reflect consistency with UL product testing practices and changes that reflect the extended cope of the standard itself. According to author, consumers will benefit from these changes.