Iron intake

Van Cauwenbbrgh, Hendrix P, Robberecht H, Deelstra H (1997) Daily dietary iron intake in Belgium using duplicate portion sampling. Z Lebensm Unters Forsch 205A 4oi-4o6. 

Sufficient dietary iron intake must be maintained in patients with anemia of CKD. Approximately 1 to 2 mg of iron is... 

Recommend appropriate folic acid, calcium, and iron intake prior to conception. 

Hammad TA, Sexton M, Langenberg P. 1996. Relationship between blood lead and dietary iron intake in preschool children. A cross-section study. Ann Epidemiol 6(1) 30-33. 

Chronic iron intake Individuals with normal iron balance should not take iron chronically. 

The effecf of fhe source of Ca on fhe magnifude of Ca-Fe interactions in vivo was assessed in rodents (Smith, 1988), using a whole body radioisotopic retention test as an endpoint to determine true iron bioavailability (i.e., Fe that is absorbed and utilized). A single 50 gg liquid dose of Fe-labeled FeCla was administered by oral gavage to rats at a Ca Fe ratio of 60 1 and 120 1 fo replicate a human iron intake of 15 mg/day and a Ca intake of 800 mg/day or 1600 mg/day, respectively. Ca sources included CaCOa, Ca Phosphate (CaP), bone meal, and Ca hydroxyapatite (CaHA), while the control dose contained no Ca and was normalized to represent 100% Fe retention for comparison purposes. Isotope counts were performed immediafely after dosing (to measure 100% retention) and subsequent counts over 6 days were divided by the 100% count to estimate Fe retention. For CaCOa, Fe retention was 68% at a Ca Fe ratio of 60 1, and only declined a furfher 2% when the ratio was increased to 120 1. Fe retention values for ofher forms of Ca at a 60 1 Ca Fe ratio were as follows 77% for bone meal, 89% for CaP, and 99% for CaHA. Fe retention decreased in response to the higher Ca Fe ratio of 120 1 (i.e., Fe retention in the presence of bone meal, CaHA, and CaP was 49%, 72%, and 78%, respecfively). This is indicative of a dose-response effect of Ca on Fe retention. This sfudy also underscored fhe importance of the source of Ca in relation fo Fe refenfion. 

An intake of 25—75 mg Fe d may be safe. Long term iron overload has been noted in South Africa (Bantu siderosis). Ingestion of up to 200 mg Fe d-1 may be the result of eating food cooked in iron pots or drinking Kaffir beer containing 15-120 mg Fe 1 1. Ethiopians have a high iron intake (up to 500 mg d-1), but as siderosis is not common, much of this iron must be unavailable.33 This type of hemosiderosis should be treated by preventative measures to restrict the amount of iron in the diet.48... 

Cunnane, S.C., McAdoo, K.R., and Horrobin, D.F. 1987. Horrobin, iron intake influences essential fatty acids and lipid composition of rat plasma and erythrocyts. J. Nutr. 117, 1514-1519. 

In animal models of atherosclerosis, vascular iron deposit is closely related to the progression of atherosclerosis and LDL oxidation, and restriction in dietary iron intake leads to significant inhibition of lesion formation (8), DFO forms a stable complex with ferric iron and decreases its availability for the production of reactive-oxygen species (28). Moreover, in high concentration (>0.5 mmol/L), DFO may also scavenge... 

Hb is low - generally due to reduced iron intake or possibly excessive iron loss... 

Iron is another essential metal that can overload the body as a result of genetic disorders. Hereditary hemochromatosis and sub-Saharan African hemochromatosis are two examples. These two disorders differ in that hereditary hemochromatosis results in excessive iron when iron intake levels are normal, while sub-Saharan African hemochromatosis requires excessive intake of Fe coupled with a genetic predisposition to poorly regulate iron. Generally speaking, toxicity associated with excess essential metals tends to be rare, and it most frequently occurs in people who inappropriately consume dietary supplements. 

Table VII. Manganese Utilization as Affected by Iron Intake at Two Levels of Manganese Intake...

The effects of exercise on the dietary needs for minerals have not been extensively studied. Of particular interest is the impact of exercise on the minerals iron and calcium which are examined in Chapter 7. Iron is an essential component of hemoglobin which is responsible for transport of oxygen within red blood cells in the blood. Thus, iron defioiency (anemia) will decrease oxygen carrying capacity of the blood and hence lower aerobic capacity. This problem appears to be most important for women who frequently have marginal iron intakes ( 5). 

Prolonged heavy excess of iron intake overwhelms the mechanism described and results in haemo-siderosis, as there is no physiological mechanism to increase iron excretion in the face of increased absorption. Iron-deficient subjects absorb up to 20 times as much administered iron as those with normal stores. Abnormalities of the small intestine may interfere with either the absorption of iron, as in coeliac disease and other malabsorption syndromes, or possibly with the conversion of iron into a soluble and reduced form, e.g. following loss of acid secretion after a partial gastrectomy. 

Humans are uniquely unable to excrete excess iron so that, if there is uncontrolled iron intake, it progressively accumulates. Grossly excessive parenteral iron therapy or a hundred or more blood transfusions (as in treatment of thalassaemia ) can lead to haemosiderosis. Oral iron therapy over many years has also been reported to cause haemosiderosis. 

Reduced iron is found in infections or chronic inflammations, in neoplasms as a distributive disorder (1. e. shift of the serum iron pool to the macrophages), or as iron deficiency (i.e. due to reduced iron intake or a decline in transferrin synthesis). Iron deficiency can also appear during liver cirrhosis due to occult bleeding. 

The use of antioxidants is plausible from a pharmacological point of view, since lipid peroxidation due to iron intake may indeed lead to further tissue damage. (460) Silymarin (e.g. 2 x 140-170 mg), vitamin E (e.g. 100-200 mg) or p-carotene are good choices due to their lack of side effects and plausibility of efficacy. 

Wurzehnann JI, Silver A, Schreinemachers DM, Sandler RS, Everson RB. Iron intake and the risk of colorectal cancer. Cancer Epidemiol Biomarkers Prev 1996 5(7) 503-7. 

Iron is used to regenerate hemoglobin. Iron is absorbed in the intestine and enters plasma as heme. Iron is stored as ferritin in the liver, spleen, and bone marrow. Five to twenty milligrams of iron are required daily. Iron deficiency causes anemia. Iron is found in liver, lean meats, egg yolks, dried beans, green vegetables (i.e., spinach), and fruit. Women who are pregnant should increase their iron intake as specified by the healthcare provider. Large doses of iron are prescribed in the second and third trimesters. The patient must adhere to the... 

How should pregnant women adjust their iron intake ... 

Pregnant women should increase their iron intake as specified by the healthcare provider. Large doses of iron are prescribed in the second and third trimesters. The patient must adhere to the prescribed dose in the first trimester to avoid birth defects. 

The 1977-78 Nationwide Pood Consumption Survey (.MFCS) recently published by the USDA (i) outlines the following findings as related to iron intake in the U.S. ... 

The iron intake of infants in 1977 was more than twice the intake in 1965 However, the average intake of 1 to 2 year olds was much lower, about 5% below the 197 RDA. 

Figure 2. Effect of iron intake on the hemoglobin concentration in the rat. Diets contained either 10% (O)or 20% (A) protein (5).

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