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The effect of fortification iron (reduced iron) on zinc absorption from a commercial vegetable-based weaning food was assessed in 11 9-mo-old infants. Each infant was fed a test meal of unfortified or iron-fortified product, labeled... more
The effect of fortification iron (reduced iron) on zinc absorption from a commercial vegetable-based weaning food was assessed in 11 9-mo-old infants. Each infant was fed a test meal of unfortified or iron-fortified product, labeled extrinsically with 1 mg 67Zn or 70Zn (as citrate), and the next day was fed the second product labeled with the other isotope. A complete fecal collection was carried out for 3-4 d, and the amount of unabsorbed isotope measured by thermal-ionization quadrupole mass spectrometry. Apparent zinc absorption (isotope intake minus fecal excretion, expressed as the % of dose administered) was 31.1 +/- 8.3% (x +/- SD) from the iron-fortified food and 28.6%28.6 +/- 10.5% from the unfortified food. These values were not significantly different, thus iron fortification of the weaning food did not reduce zinc absorption.
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Fairweather‐Tait, S. J. (AFRC Institute of Food Research, Colney Lane, Norwich NR4 7UA, Norfolk, UK) Iron and its availability.The iron stores of full‐term, breast‐fed infants become depleted by the age of 6 months, but this may occur... more
Fairweather‐Tait, S. J. (AFRC Institute of Food Research, Colney Lane, Norwich NR4 7UA, Norfolk, UK) Iron and its availability.The iron stores of full‐term, breast‐fed infants become depleted by the age of 6 months, but this may occur earlier when they are fed formula that is not fortified with iron. There is a high requirement for iron, and therefore the selection of appropriate weaning foods is critical at this time. Continued consumption of breast milk or iron‐fortified formulas until the age of one year will help maintain an adequate iron status, particularly in infants given diets of low iron availability. Many dietary constituents affect the availability of inorganic iron from foods, the most important ones in the case of the infant are ascorbic acid and haem iron, both of which enhance the absorption of inorganic iron. The majority of commercially‐prepared infant foods contain added iron and ascorbic acid, thereby providing sufficent absorbable iron for the growing infant. On...
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... Susan J. Fairweather-Tait, Lisa L. Symss, Andrew C. Smith and Ian T. Johnson AFRC Institute of Food Research, Norwich Laboratory, Colney Lane, Norwich NR4 7UA. UK ... 185-191. Page 8. 348 SJ Fairweather-Tait, LL Symss, AC Smith, IT... more
... Susan J. Fairweather-Tait, Lisa L. Symss, Andrew C. Smith and Ian T. Johnson AFRC Institute of Food Research, Norwich Laboratory, Colney Lane, Norwich NR4 7UA. UK ... 185-191. Page 8. 348 SJ Fairweather-Tait, LL Symss, AC Smith, IT Johnson ...
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Plasma 25‐hydroxy‐vitamin D and breast‐milk calcium concentration were measured at 3 months of lactation in 60 Gambian mothers accustomed to a low calcium diet, of whom 30 were consuming a calcium supplement and 30 were receiving a... more
Plasma 25‐hydroxy‐vitamin D and breast‐milk calcium concentration were measured at 3 months of lactation in 60 Gambian mothers accustomed to a low calcium diet, of whom 30 were consuming a calcium supplement and 30 were receiving a placebo, and in 48 British mothers. The plasma 25‐hydroxy‐vitamin D concentration of the Gambian women was not affected by either calcium supplementation (supplemented, 64. 4 ± 2. 5 nmol 1‐1; placebo, 64. 9 ± 3. 5 nmol l‐1; mean ± SE) or season. The British average was lower (53. 9 ± 3. 0 nmol 1‐1, p= 0. 004), owing to marked seasonal effects. The breast‐milk calcium concentration was lower in The Gambia (supplemented, 5. 38 ± 0. 13 mmol 1‐1; placebo, 5. 10 ± 0. 13mmol 1‐1; British, 6. 93 ± 0. 15 mmol 1‐1, p < 0. 0001). There was no relationship between plasma 25‐hydroxy‐vitamin D and breast‐milk calcium concentration in any group. There was no trend towards lower breast‐milk calcium concentration in women with vitamin D status towards the bottom of th...
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Iron absorption from a typical Gambian meal of rice with groundnut sauce was measured by the fecal balance technique in nonanemic adult males with 58Fe as an extrinsic label and neutron activation analysis and compared with ferrous... more
Iron absorption from a typical Gambian meal of rice with groundnut sauce was measured by the fecal balance technique in nonanemic adult males with 58Fe as an extrinsic label and neutron activation analysis and compared with ferrous sulphate. Gambian men had a higher efficiency of absorption than UK volunteers but the availability of the food Fe was approximately half that of ferrous sulphate in both groups of subjects.
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Research Interests: Chemistry, Chromatography, Mass Spectrometry, Medicine, Genetic Algorithm, and 14 moreHumans, Child, Animals, Meat, Zinc, Inductively Coupled Plasma Mass Spectrometry, Trace Elements, High Pressure Liquid Chromatography, Chickens, Trace element, Sensitivity and Specificity, Biochemistry and cell biology, Zinc isotopes, and Medical biochemistry and metabolomics
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Water-loss dehydration (hypertonic, hyperosmotic, or intracellular dehydration) is due to insufficient fluid intake and is distinct from hypovolemia due to excess fluid losses. Water-loss dehydration is associated with poor health... more
Water-loss dehydration (hypertonic, hyperosmotic, or intracellular dehydration) is due to insufficient fluid intake and is distinct from hypovolemia due to excess fluid losses. Water-loss dehydration is associated with poor health outcomes such as disability and mortality in older people. Urine specific gravity (USG), urine color, and urine osmolality have been widely advocated for screening for dehydration in older adults. We assessed the diagnostic accuracy of urinary measures to screen for water-loss dehydration in older people. This was a diagnostic accuracy study of people aged ≥65 y taking part in the DRIE (Dehydration Recognition In our Elders; living in long-term care) or NU-AGE (Dietary Strategies for Healthy Ageing in Europe; living in the community) studies. The reference standard was serum osmolality, and index tests included USG, urine color, urine osmolality, urine cloudiness, additional dipstick measures, ability to provide a urine sample, and the volume of a random u...
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An improved understanding of copper metabolism is needed to derive more precise estimates of dietary requirements. The objectives were to validate a method for estimating endogenous losses of copper, test whether a simple model can... more
An improved understanding of copper metabolism is needed to derive more precise estimates of dietary requirements. The objectives were to validate a method for estimating endogenous losses of copper, test whether a simple model can predict true absorption from the plasma appearance of labeled copper, and develop a compartmental model for copper metabolism by using stable isotopes. A stable isotope of copper was intravenously administered to 6 men, and fecal samples were collected for 14 d. Four weeks later the study was repeated, but with an oral dose, and blood samples were collected for 7 d and fecal samples for 14 d. There was no significant difference (P = 0.48) in the estimated endogenous loss of copper calculated by using either the excreted intravenous dose (x +/- SD: 32 +/- 5%) or the absorbed and excreted oral dose (35 +/- 2%). A simple mathematical model fitted to plasma isotope appearance data estimated true absorption to be 8 +/- 2% compared with 48-49% measured by fecal...
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The addition of 1 g sugar-beet fibre (Beta Fibre) to 3 g semi-synthetic diet resulted in a 54% increase in iron and a 39% increase in zinc absorption in rats. The same amount of non-starch polysaccharides fed as wheat bran (1.9 g) had no... more
The addition of 1 g sugar-beet fibre (Beta Fibre) to 3 g semi-synthetic diet resulted in a 54% increase in iron and a 39% increase in zinc absorption in rats. The same amount of non-starch polysaccharides fed as wheat bran (1.9 g) had no effect on Fe absorption but reduced Zn absorption by 9%. The inhibitory effect of wheat bran is probably due to its high phytate content, but there is, as yet, no explanation for the enhancement of Fe and Zn absorption caused by Beta Fibre. If the effect also occurs in man, it will have important implications for high-fibre diets and mineral nutrition.
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1. Iron and zinc retentions in young male rats, given 3 g starch–sucrose paste containing 120 μg Fe as FeSO4or 139 μg Zn as ZnC12(extrinsically labelled with59Fe or65Zn) and increasing amounts ofGypsophilasaponins, were measured by... more
1. Iron and zinc retentions in young male rats, given 3 g starch–sucrose paste containing 120 μg Fe as FeSO4or 139 μg Zn as ZnC12(extrinsically labelled with59Fe or65Zn) and increasing amounts ofGypsophilasaponins, were measured by whole-body counting. The results were compared with whole-body Fe and Zn retention from a meal containing crude or purified saponin fractions. In a separate experiment Fe retention from a meal containingGypsophilasaponins, soyasaponin I, or saponins extracted from lucerne (Medicago sativa) plant tops, was measured in older rats.2. Results indicated that Fe absorption decreased with increasing concentration ofGypsophilasaponins. This was significant at a saponin: Fe molar value of approximately 1, with maximum effect occurring at molar ratios of 4 and above, when Fe absorption was reduced by approximately 17%.Gypsophilasaponins had no effect on Zn absorption from a test meal.3. Fe absorption was similar in groups given purified or crudeGypsophilasaponins a...
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Rats were weaned onto high (HCa, 14.6 g/kg)- or low (LCa, 3.88 g/kg)-Ca diets for 12 d and the efficiency of absorption of Ca measured from 20 mg Ca (as CaCl2, labelled with 47Ca) by means of wholebody counting. The LCa group absorbed 74... more
Rats were weaned onto high (HCa, 14.6 g/kg)- or low (LCa, 3.88 g/kg)-Ca diets for 12 d and the efficiency of absorption of Ca measured from 20 mg Ca (as CaCl2, labelled with 47Ca) by means of wholebody counting. The LCa group absorbed 74 % of the test dose and the HCa group 60 % of the test dose (P < 0.001). All animals were then given the LCa diet for 6 weeks and the absorption test repeated. This time there was no difference in efficiency of absorption (HCa 54%, LCa 57%). The femur dry weight was significantly lower in the group initially fed on the LCa diet, but the Ca concentration was similar to that of the HCa group. The results do not lend support to the suggestion that early dietary exposure to Ca manifests itself as a difference in Ca metabolism in later life. They do, however, highlight the importance of adequate Ca intake during critical periods of growth.
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1. The availability of iron, zinc and calcium in a diet containing 400 g ‘fibre-filler’ (a mixture of bran, fruit and nuts, used in the F-plan diet)/kg diet (HF diet) was measured by whole-body counting in rats, using59Fe,66Zn and47Ca as... more
1. The availability of iron, zinc and calcium in a diet containing 400 g ‘fibre-filler’ (a mixture of bran, fruit and nuts, used in the F-plan diet)/kg diet (HF diet) was measured by whole-body counting in rats, using59Fe,66Zn and47Ca as extrinsic labels, and compared with a diet of similar mineral content but no ‘fibre-filler’ (LF diet). Absorption of Fe and Ca was significantly higher from the HF than from the LF diet but there was no difference in Zn availability between the two diets.2. The ability of rats given LF or HF diets for 3 or 28 d to absorb Fe, Zn and Ca was measured using ferrous sulphate, zinc chloride and calcium chloride in a cooked starch-sucrose (1: 1 w/w) paste, extrinsically-labelled with the appropriate isotope. There was no difference in Fe absorption between the HF- and LF-fed groups but both Zn and Ca absorption were higher in LF- than in HF-fed animals after 3 and 28 d.3. The mineral status of the animals given HF or LF diets for 28 d was examined, and the...
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1. Iron retention from 3 g wholewheat flour was measured in male Wistar rats previously given one high-Fe or control diet meal 12,24, 36,48 or 60 h before the test meal (Expt 1). The control diet was given at all other times. The... more
1. Iron retention from 3 g wholewheat flour was measured in male Wistar rats previously given one high-Fe or control diet meal 12,24, 36,48 or 60 h before the test meal (Expt 1). The control diet was given at all other times. The procedure was then repeated in rats given one high- or low-Fe meal 12, 24, 36 or 48 h before the test meal (Expt 2).2. There was a significant difference between groups given a high- or medium-Fe meal at 12,24,36 h (P < 0.001) and 48 h (P < 0.05) but not at 60 h. In the second experiment, there was a significant difference between groups given a high- or low-Fe meal at 12, 24 or 36 h but no difference when given the two diets 48 h before the test meal. The high-Fe meal depressed and the low-Fe meal enhanced subsequent59Fe retention: the effects were greatest at 12 h and diminished as the time interval between the high- or low-Fe meal and the test meal increased. The estimated mean time for the absorptive capacity of the mucosal cells to return to equi...
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High salt intake is a well‐recognized risk factor for osteoporosis because it induces calciuria, but the effects of salt on calcium metabolism and the potential impact on bone health in postmenopausal women have not been fully... more
High salt intake is a well‐recognized risk factor for osteoporosis because it induces calciuria, but the effects of salt on calcium metabolism and the potential impact on bone health in postmenopausal women have not been fully characterized. This study investigated adaptive mechanisms in response to changes in salt and calcium intake in postmenopausal women. Eleven women completed a randomized cross‐over trial consisting of four successive 5‐wk periods of controlled dietary intervention, each separated by a minimum 4‐wk washout. Moderately low and high calcium (518 versus 1284 mg) and salt (3.9 versus 11.2 g) diets, reflecting lower and upper intakes in postmenopausal women consuming a Western‐style diet, were provided. Stable isotope labeling techniques were used to measure calcium absorption and excretion, compartmental modeling was undertaken to estimate bone calcium balance, and biomarkers of bone formation and resorption were measured in blood and urine. Moderately high salt in...
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Estimated average requirements for micronutrients are central to deriving Dietary Reference Values. These are used for nutrition policies and programs, and also for regulatory and labeling purposes, and are traditionally devised to cover... more
Estimated average requirements for micronutrients are central to deriving Dietary Reference Values. These are used for nutrition policies and programs, and also for regulatory and labeling purposes, and are traditionally devised to cover the needs of virtually all individuals in any population group. In order to estimate the average requirement, an appropriate endpoint (biomarker) is selected which describes the relationship between dietary intake and health. However, for some micronutrients, such as zinc, there are no good biomarkers, and for others, such as iron, the intake-status relationship is confounded by variations in absorption. Average requirements for these nutrients are derived using a factorial approach in which physiological needs for tissue growth and maintenance and endogenous losses are estimated, and the total converted to a dietary requirement by taking into account the overall absorption from the diet; i. e. multiplying the requirement by a bioavailability factor...
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A well established stable isotope technique exists for measuring calcium absorption from single foods and meals, but the long term effects of calcium on bone health cannot be assessed from acute bioavailability studies. Bone health... more
A well established stable isotope technique exists for measuring calcium absorption from single foods and meals, but the long term effects of calcium on bone health cannot be assessed from acute bioavailability studies. Bone health depends primarily on the degree of mineralization, measured as bone mineral density (BMD), and phenotypic variations depend on genetic and environmental factors including calcium supply. Since almost all retained calcium is used for bone mineralization and remodeling, BMD can be used as a long-term (> six months) marker of dietary calcium bioavailability. However, BMD is a very insensitive marker of calcium bioavailability, so its use in dietary intervention studies is restricted to periods of significant bone growth or loss. Biochemical markers of bone metabolism may be used to predict the overall bioavailability of dietary calcium over a shorter time period (> four weeks), but they have a high coefficient of variation, so may not be appropriate fo...
Research Interests: Endocrinology, Chemistry, Nutrition and Dietetics, Calcium, Health, and 15 moreDensity, Medicine, Human Nutrition, Osteoporosis, Humans, Bone Density, Absorption, Bioavailability, Intestinal absorption, Calcium Metabolism, Biological markers, Micronutrient, Biological Availability, bone development, and excretion
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Research in both animals and humans shows that some nutrients are important in pregnancy and during the first years of life to support brain and cognitive development. Our aim was to evaluate the role of selenium (Se) in supporting brain... more
Research in both animals and humans shows that some nutrients are important in pregnancy and during the first years of life to support brain and cognitive development. Our aim was to evaluate the role of selenium (Se) in supporting brain and behavioral plasticity and maturation. Pregnant and lactating female rats and their offspring up to postnatal day 40 were fed isocaloric diets differing in Se content—i.e., optimal, sub-optimal, and deficient—and neurodevelopmental, neuroinflammatory, and anti-oxidant markers were analyzed. We observed early adverse behavioral changes in juvenile rats only in sub-optimal offspring. In addition, sub-optimal, more than deficient supply, reduced basal glial reactivity in sex dimorphic and brain-area specific fashion. In female offspring, deficient and sub-optimal diets reduced the antioxidant Glutathione peroxidase (GPx) activity in the cortex and in the liver, the latter being the key organ regulating Se metabolism and homeostasis. The finding that...
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Background Maintenance of high physical performance during aging might be supported by an adequate dietary intake of niacin, vitamins B-6 and B-12, and folate because these B vitamins are involved in multiple processes related to muscle... more
Background Maintenance of high physical performance during aging might be supported by an adequate dietary intake of niacin, vitamins B-6 and B-12, and folate because these B vitamins are involved in multiple processes related to muscle functioning. However, not much is known about the association between dietary intake of these B vitamins and physical performance. Objectives The objectives of this study were to investigate the association between dietary intake of niacin, vitamins B-6 and B-12, and folate and physical performance in older adults and to explore mediation by niacin status and homocysteine concentrations. Methods We used baseline data from the New Dietary Strategies Addressing the Specific Needs of the Elderly Population for Healthy Aging in Europe (NU-AGE) trial, which included n = 1249 healthy older adults (aged 65–79 y) with complete data on dietary intake measured with 7-d food records and questionnaires on vitamin supplement use and physical performance measured ...
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1. Female Wistar rats were given an adequate-zinc (60 μg/g) or low-Zn (7 μg/g) diet for a minimum of 2 weeks and then mated. They were then either continued on the same diets (+Zn –Fe or –Zn –Fe) or given similar diets supplemented with... more
1. Female Wistar rats were given an adequate-zinc (60 μg/g) or low-Zn (7 μg/g) diet for a minimum of 2 weeks and then mated. They were then either continued on the same diets (+Zn –Fe or –Zn –Fe) or given similar diets supplemented with four times the normal level of iron (+Zn + Fe or –Zn + Fe). The day before parturition they were killed and the fetuses removed and analysed.2. There were no differences in numbers of fetuses or the number of resorption sites. In the absence of Fe supplementation, the mean fetal wet weight was significantly less (P< 0.05) in the low-Zn group but there was no effect of Zn in the two Fe-supplemented groups. The addition of Fe significantly decreased (P< 0.05) the mean fetal wet weight in the adequate-Zn groups but had no effect in the low-Zn groups. There were no differences in fetal dry weight, fat, protein or DNA content. Both Fe-supplemented groups produced fetuses of higher Fe concentration (P< 0.01), and mothers with higher bone Fe-concen...
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1. Iron absorption was studied in weanling rats using balance techniques from semi-synthetic diets containing dried white bread (60·5 g dietary fibre/kg, White & Southgate, unpublished results), brown bread (130·2 g dietary fibre/kg) or... more
1. Iron absorption was studied in weanling rats using balance techniques from semi-synthetic diets containing dried white bread (60·5 g dietary fibre/kg, White & Southgate, unpublished results), brown bread (130·2 g dietary fibre/kg) or wholemeal bread (221·2 g dietary fibre/kg) at a level of 300 g/kg and compared with a control group given a diet containing added FeSO4 at a similar Fe level to that for the bread groups. The dried bread contained 6·2–6·4 g phytate/kg.2. Absorption of Fe was significantly higher (P < 0·001) in the control group (0·45) than in the white (0·28), brown (0·31) or wholemeal (0·24) groups.3. A second experiment was carried out on 6-week-old rats in which the dried bread was extrinsically labelled with 59Fe and absorption from a single meal measured by both faecal excretion and incorporation of 59Fe into the blood. Control animals were given 59FeSO4 for comparison.4. The excretion of 59Fe (% of administered dose) was significantly lower (P < 0·001) in...
Research Interests: Chemistry, Nutrition and Dietetics, Food Science, Medicine, Animal Production, and 13 moreBread, Animals, Male, Iron, Absorption, Rats, Dietary fiber, Feces, Food Sciences, Meal, Triticum, Phytic acid, and excretion(Bread, Animals, Male, Iron, Absorption, Rats, Dietary fiber, Feces, Food Sciences, Meal, Triticum, Phytic acid, and excretion)
(Bread, Animals, Male, Iron, Absorption, Rats, Dietary fiber, Feces, Food Sciences, Meal, Triticum, Phytic acid, and excretion)
1. Iron availability in potatoes and ferrous sulphate was measured in rats in a 10 d balance study and from a single meal using59Fe and55Fe as extrinsic labels.2. Dried potato samples were incubated in gastric juice in vitro and the... more
1. Iron availability in potatoes and ferrous sulphate was measured in rats in a 10 d balance study and from a single meal using59Fe and55Fe as extrinsic labels.2. Dried potato samples were incubated in gastric juice in vitro and the amount solubilized was compared with other foods. The relationship between ascorbic acid content of dried potato and Fe solubilization was examined in vitro.3. In the balance study, the rats absorbed (mean with SE) 15·2 (2·7)% Fe from the diet containing 660 g dried potato/kg and 32·1 (2·8)% Fe from the semi-synthetic diet containing FeSO4. Absorption was higher from the extrinsically-labelled single meal: 49·6 (1·1)% Fe from59Fe-labelled potato and 62·4 (1·2)% Fe from59FeSO4.4. The in vitro experiments showed a much greater solubilization of Fe from potato than from the other foods examined. There was a correlation between Fe solubilization and ascorbic acid content of potatoes (rs0·76,P< 0·00).5. It appears that potatoes contain Fe of moderate avail...
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An international workshop of invited experts and partners in the EC-funded Network of Excellence, EURRECA (www.eurreca.org) was held in Norwich on 18–20 February 2008 to discuss biomarkers of micronutrient status.
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1. The potential use of an extrinsic label to measure iron absorption from a ferric orthophosphate-fortified malted cocoa drink was examined by measuring the solubility of the FePO4 in 0·1 M-hydrochloric acid.2. The validity of using the... more
1. The potential use of an extrinsic label to measure iron absorption from a ferric orthophosphate-fortified malted cocoa drink was examined by measuring the solubility of the FePO4 in 0·1 M-hydrochloric acid.2. The validity of using the stable isotope 58Fe as an extrinsic label was tested by comparing Fe absorption by rats from wheat flour extrinsically-labelled with 58Fe or 59Fe.3. Fe absorption from a malted cocoa drink (20 g powder made up with hot water) fortified with FePO4 (0·5 mg Fe/g powder) was measured in human subjects using 58Fe as an extrinsic label. Absorption was calculated by measuring unabsorbed 58Fe in faeces. Absorptions of Fe from the drink fortified with either FePO4 or ferrous sulphate were compared. The effect of the addition of ascorbic acid to the drink (1 mg/g powder) on Fe availability was also examined.4. The effect of fasting on Fe absorption from the drink was determined in rats by giving the drink to fasting animals or shortly after they had consumed ...
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Absorption from wheat intrinsically and extrinsically labelled with 67Zn and extrinsically labelled with 65Zn was measured from 67Zn faecal excretion and 6sZn whole-body retention in rats. There were significant differences between the... more
Absorption from wheat intrinsically and extrinsically labelled with 67Zn and extrinsically labelled with 65Zn was measured from 67Zn faecal excretion and 6sZn whole-body retention in rats. There were significant differences between the extrinsically- and intrinsically-labelled 67Zn (P < 0·001), but not between the extrinsically-labelled 65Zn and intrinsically-labelled 67Zn. The effect of chicken meat on the absorption of Zn from intrinsically-labelled wheat was also studied in the rat. Mean Zn absorption from wheat and chicken meat fed separately was 18·5 and 68·2% respectively, and from a mixture of the two containing the same level of Zn was 50·1%. The apparent absorption of Zn from the composite meal was significantly higher than predicted from the results of the foods on their own (P < 0·001).
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1. The effect of heat treatment of bran on true zinc absorption was measured using an isotope-dilution technique. A bran-based breakfast cereal (heated to 204° for 40 min during manufacture) was incorporated into a semi-synthetic diet at... more
1. The effect of heat treatment of bran on true zinc absorption was measured using an isotope-dilution technique. A bran-based breakfast cereal (heated to 204° for 40 min during manufacture) was incorporated into a semi-synthetic diet at a level of 180 g/kg, A parallel diet was formulated containing an identical weight of untreated bran from the same source plus other ingredients used to make the cereal.2. Young male Wistar rats (mean weight 80 g) were injected intramuscularly with 65Zn to label body Zn. They were given the heat-treated- and untreated-bran diets for 9 d. During the last 6 d of this period Zn intakes and faecal and urinary Zn were measured in order to calculate apparent Zn retention. True Zn retention was measured by taking into account losses of Zn of endogenous origin (labelled with 65Zn), by measuring faecal and urinary 65Zn taking the mean specific radioactivity of Zn in kidneys and upper small intestine to represent specific radioactivity of endogenous origin.3....
Research Interests: Chemistry, Nutrition and Dietetics, Animal Science, Medicine, Animal Production, and 11 moreAnimals, Male, Zinc, Iron, Cereals, Intestinal absorption, Rats, Particle Size, Dietary fiber, Food Sciences, and Phytic acid(Animals, Male, Zinc, Iron, Cereals, Intestinal absorption, Rats, Particle Size, Dietary fiber, Food Sciences, and Phytic acid)
(Animals, Male, Zinc, Iron, Cereals, Intestinal absorption, Rats, Particle Size, Dietary fiber, Food Sciences, and Phytic acid)
Fe homeostasis is considered in the context of the UK diet, using information on Fe intake and status from the National Diet and Nutrition Surveys. The importance of assessing Fe availability rather than total Fe intake is discussed.... more
Fe homeostasis is considered in the context of the UK diet, using information on Fe intake and status from the National Diet and Nutrition Surveys. The importance of assessing Fe availability rather than total Fe intake is discussed. Dietary and host-related factors that determine Fe bioavailability (Fe utilised for Hb production) are reviewed using information from single-meal studies. When adaptive responses are taken into consideration, foods associated with higher Fe status include meat (haem-Fe and the ‘meat factor’) and fruits and fruit juice (vitamin C). Foods that may have a negative impact include dairy products (Ca), high-fibre foods (phytate) and tea and coffee (polyphenols), but the effects are more apparent in groups with marginal Fe deficiency, such as women of childbearing age. Analysis of dietary intake data on a meal-by-meal basis is needed to predict the influence of changing dietary patterns on Fe nutrition in the UK. Current information suggests that in the UK Fe...