Iron — Health Professional Fact Sheet. Introduction. Iron is a mineral that is naturally present in many foods, added to some food products, and available as a dietary supplement. Iron is an essential component of hemoglobin, an erythrocyte protein that transfers oxygen from the lungs to the tissues . ![]() As a component of myoglobin, a protein that provides oxygen to muscles, iron supports metabolism . Iron is also necessary for growth, development, normal cellular functioning, and synthesis of some hormones and connective tissue . Plants and iron- fortified foods contain nonheme iron only, whereas meat, seafood, and poultry contain both heme and nonheme iron . Heme iron, which is formed when iron combines with protoporphyrin IX, contributes about 1. Much of the remaining iron is stored in the form of ferritin or hemosiderin (a degradation product of ferritin) in the liver, spleen, and bone marrow or is located in myoglobin in muscle tissue . Humans typically lose only small amounts of iron in urine, feces, the gastrointestinal tract, and skin. ![]() Disease Prevention Cardiovascular disease Choline and homocysteine. A large body of research indicates that even moderately elevated levels of homocysteine in the. Home July 3rd 2017 Sebastian Kienle: Three Times. Defending champion Sebastian Kienle could be the first athlete to take the IRONMAN European. Read More News June. Vegetarian recipes and nutrition information dedicated to educating the public on vegetarianism and the interrelated issues of health, nutrition, ecology, ethics, and. 6 necessary comic books sketching a more inclusive narrative The buzz around the film Black Panther due for release in February 2018 has brought to the fore. Health Watch: Teen saves fellow student from choking on a cheese curd. Watch: Teen saves fellow student from choking on a cheese curd A cafeteria security camera. Losses are greater in menstruating women because of blood loss. Hepcidin, a circulating peptide hormone, is the key regulator of both iron absorption and the distribution of iron throughout the body, including in plasma . Measures of serum ferritin can be used to identify iron depletion at an early stage . A reduced rate of delivery of stored and absorbed iron to meet cellular iron requirements represents a more advanced stage of iron depletion, which is associated with reduced serum iron, reticulocyte hemoglobin, and percentage transferrin saturation and with higher total iron binding capacity, red cell zinc protoporphyrin, and serum transferrin receptor concentration. The last stage of iron deficiency, characterized by iron- deficiency anemia (IDA), occurs when blood hemoglobin concentrations, hematocrit (the proportion of red blood cells in blood by volume), mean corpuscular volume, and mean cell hemoglobin are low . Hemoglobin and hematocrit tests are the most commonly used measures to screen patients for iron deficiency, even though they are neither sensitive nor specific . Hemoglobin concentrations lower than 1. L in men and 1. 2 g/d. ![]() L in women indicate the presence of IDA . Normal hematocrit values, which are generally three times higher than hemoglobin levels, are approximately 4. DRI is the general term for a set of reference values used for planning and assessing nutrient intakes of healthy people. These values, which vary by age and gender, include: Recommended Dietary Allowance (RDA): average daily level of intake sufficient to meet the nutrient requirements of nearly all (9. Adequate Intake (AI): established when evidence is insufficient to develop an RDA; intake at this level is assumed to ensure nutritional adequacy. Estimated Average Requirement (EAR): average daily level of intake estimated to meet the requirements of 5. It is usually used to assess the adequacy of nutrient intakes in population groups but not individuals. Tolerable Upper Intake Level (UL): maximum daily intake unlikely to cause adverse health effects. Table 1 lists the current iron RDAs for nonvegetarians. The RDAs for vegetarians are 1. This is because heme iron from meat is more bioavailable than nonheme iron from plant- based foods, and meat, poultry, and seafood increase the absorption of nonheme iron . Get the latest health news, diet & fitness information, medical research, health care trends and health issues that affect you and your family on ABCNews.com. Read about esophageal cancer staging, causes, symptoms, treatment, life expectancy, survival rate, and prognosis. Learn about the relationship between Barrett's. Atlas Venture has raised its 11th fund, totaling $350 million. Dietary sources of nonheme iron include nuts, beans, vegetables, and fortified grain products. In the United States, about half of dietary iron comes from bread, cereal, and other grain products . Breast milk contains highly bioavailable iron but in amounts that are not sufficient to meet the needs of infants older than 4 to 6 months . Infant formulas are fortified with 1. The bioavailability of iron is approximately 1. While it may be surprising to see floating poop, it's usually nothing to be concerned about and is often related to something you had to eat. Here are the two main. ![]() C (ascorbic acid, which enhances the bioavailability of nonheme iron) and 5% to 1. In addition to ascorbic acid, meat, poultry, and seafood can enhance nonheme iron absorption, whereas phytate (present in grains and beans) and certain polyphenols in some non- animal foods (such as cereals and legumes) have the opposite effect . Unlike other inhibitors of iron absorption, calcium might reduce the bioavailability of both nonheme and heme iron. However, the effects of enhancers and inhibitors of iron absorption are attenuated by a typical mixed western diet, so they have little effect on most people’s iron status. Several food sources of iron are listed in Table 2. Some plant- based foods that are good sources of iron, such as spinach, have low iron bioavailability because they contain iron- absorption inhibitors, such as polyphenols . DVs were developed by the U. S. Food and Drug Administration (FDA) to help consumers compare the nutrient contents of products within the context of a total diet. The DV for iron is 1. ![]() Not sure how to use this Database? Watch this Short Video!Have a grocery coupon you don't see here? Please submit it to be included here.![]() Foods providing 2. DV are considered to be high sources of a nutrient. ![]() ![]() The U. S. Department of Agriculture’s (USDA’s) Nutrient Database Web site . Multivitamin/multimineral supplements with iron, especially those designed for women, typically provide 1. DV). Multivitamin/multimineral supplements for men or seniors frequently contain less or no iron. Iron- only supplements usually deliver more than the DV, with many providing 6. DV). Frequently used forms of iron in supplements include ferrous and ferric iron salts, such as ferrous sulfate, ferrous gluconate, ferric citrate, and ferric sulfate . Because of its higher solubility, ferrous iron in dietary supplements is more bioavailable than ferric iron . High doses of supplemental iron (4. Other forms of supplemental iron, such as heme iron polypeptides, carbonyl iron, iron amino- acid chelates, and polysaccharide- iron complexes, might have fewer gastrointestinal side effects than ferrous or ferric salts . For example, ferrous fumarate is 3. Fortunately, elemental iron is listed in the Supplement Facts panel, so consumers do not need to calculate the amount of iron supplied by various forms of iron supplements. Approximately 1. 4% to 1. Americans use a supplement containing iron . Rates of use of supplements containing iron vary by age and gender, ranging from 6% of children aged 1. For this reason, some experts suggest that people take individual calcium and iron supplements at different times of the day . The average daily iron intake from foods is 1. The average daily iron intake from foods and supplements is 1. The median dietary iron intake in pregnant women is 1. Six percent of white and black toddlers aged 1 to 3 years in the United States are iron deficient (defined as at least two abnormal results for the child’s age and gender on transferrin saturation, free erythrocyte protoporphyrin, and/or serum ferritin tests), compared with 1. Hispanic toddlers . Deficiency (including IDA) is more common among children and adolescents in food- insecure households than in food- secure households . Among pregnant women, deficiency based on depleted iron stores is more common in Mexican American (2. Hispanic black women (2. Hispanic white women (1. Individuals with hereditary hemochromatosis, which predisposes them to absorb excessive amounts of dietary iron, have an increased risk of iron overload . One study suggests that elderly people are more likely to have chronic positive iron balance and elevated total body iron than iron deficiency. Among 1,1. 06 elderly white adults aged 6. Framingham Heart Study, 1. L in men and 2. 00 mcg/L in women), of which only 1% was due to chronic disease . The authors did not assess genotypes, so they could not determine whether these results were due to hemochromatosis . Because iron deficiency is associated with poor diet, malabsorptive disorders, and blood loss, people with iron deficiency usually have other nutrient deficiencies . The World Health Organization (WHO) estimates that approximately half of the 1. In developing countries, iron deficiency often results from enteropathies and blood loss associated with gastrointestinal parasites . In addition, plasma iron levels decline and plasma transferrin concentrations (measured by plasma total iron- binding capacity) rise, resulting in decreased transferrin saturation. Serum transferrin receptor concentrations also increase. IDA: Iron stores are exhausted; hematocrit and levels of hemoglobin decline; and the resulting microcytic, hypochromic anemia is characterized by small red blood cells with low hemoglobin concentrations. IDA is defined as a hemoglobin level that is lower than two standard deviations from the mean distribution in a healthy population of the same gender and age living at the same altitude . At sea level, hemoglobin concentrations lower than 1. L in children younger than 1. L in adolescents and women, and 1. L in men indicate the presence of IDA . In 2. 00. 2, the WHO characterized IDA as one of the 1. Although iron deficiency is the most common cause of anemia, deficiencies of other micronutrients (such as folate and vitamin B1. The functional deficits associated with anemia include gastrointestinal disturbances and impaired cognitive function, immune function, exercise or work performance, and body temperature regulation . In infants and children, IDA can result in psychomotor and cognitive abnormalities that, without treatment, can lead to learning difficulties . Some evidence indicates that the effects of deficiencies early in life persist through adulthood . Because iron deficiency is often accompanied by deficiencies of other nutrients, the signs and symptoms of iron deficiency can be difficult to isolate . As a result of this expansion and to meet the needs of the fetus and placenta, the amount of iron that women need increases during pregnancy. Iron deficiency during pregnancy increases the risk of maternal and infant mortality, premature birth, and low birthweight . Full- term infants usually have sufficient iron stores and need little if any iron from external sources until they are 4 to 6 months old .
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