Thomas Walczyk

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Complementary foods based on cereals may contain high amounts of phytic acid, which binds strongly to minerals and trace elements. The objective of the study was to evaluate the effect of dephytinization of a cereal-based complementary food on zinc and copper apparent absorption in adults. A dephytinized complementary food (<0.03 mg phytic acid/g) and one(More)
BACKGROUND Nonheme-iron absorption requires an acidic milieu. Reduced gastric acid output as a consequence of Helicobacter pylori infection could be an important limiting factor for iron absorption. OBJECTIVE We measured gastric acid output and iron absorption from a non-water-soluble iron compound (ferrous fumarate) and a water-soluble iron compound(More)
Ferric pyrophosphate is a water-insoluble Fe compound used to fortify infant cereals and chocolate-drink powders as it causes no organoleptic changes to the food vehicle. However, it is only of low absorption in man. Recently, an innovative ferric pyrophosphate has been developed (Sunactive Fe trade mark ) based on small-particle-size ferric pyrophosphate(More)
BACKGROUND Ascorbic acid (AA) enhances and tea inhibits iron absorption. It is unclear whether iron status influences the magnitude of this effect. OBJECTIVE We evaluated the influence of the iron status of young women on iron absorption from a rice meal with or without added tea or AA. DESIGN Two stable-isotope iron absorption studies were made in 2(More)
BACKGROUND Although ferric pyrophosphate is a promising compound for iron fortification of foods, few data are available on the effect of food matrices, processing, and ascorbic acid on its bioavailability. OBJECTIVE We compared the relative bioavailability (RBV) of ferrous sulfate in an experimental form of micronized dispersible ferric pyrophosphate(More)
Over the past two decades, new applications of inorganic mass spectrometry have been made possible by the use of stable isotopes as tracers in studies of mineral and trace element metabolism in man. Stable isotope techniques and radioisotope methods are the only reliable tools available for determination of the absorption, retention, or utilization of a(More)
UNLABELLED A new technique was evaluated to identify changes in bone metabolism directly at high sensitivity through isotopic labeling of bone Ca. Six women with low BMD were labeled with 41Ca up to 700 days and treated for 6 mo with risedronate. Effect of treatment on bone could be identified using 41Ca after 4-8 wk in each individual. INTRODUCTION(More)
The aim of the present study was to evaluate Mg absorption from a test meal served with an oxalate-rich vegetable, spinach, as compared with a test meal served with a vegetable with a low oxalate content, kale. Mg absorption was measured by a stable-isotope technique based on extrinsic labelling of the test meals and faecal monitoring of the excreted(More)
Chili and turmeric are common spices in indigenous diets in tropical regions. Being rich in phenolic compounds, they would be expected to bind iron (Fe)(3) in the intestine and inhibit Fe absorption in humans. Three experiments were conducted in healthy young women (n = 10/study) to assess the effect of chili and turmeric on Fe absorption from a rice-based(More)
Infant formula based on pea (Pisum sativum)-protein isolate has been suggested as an alternative to soybean formula in countries where soybean is not a native crop, or when soybean protein cannot be used due to allergic reactions or intolerances. In the present study, Fe absorption from experimental infant formulas based on pea-protein isolate was measured(More)