Medizin - Open Access LMU - Teil 12/22

Safety Aspects of Iron in Food


Listen Later

During the last decades efforts regarding dietary iron supply focused mostly on the prevention of deficiencies, especially during growth and pregnancy. Correspondingly, homeostatic mechanisms increase intestinal iron absorption in iron deficiency, but its downregulation at high intake levels seems insufficient to prevent accumulation of high iron stores at high intake. There is no regulated iron excretion in overload. Excess of pharmaceutical iron may cause toxicity and therapeutic doses may cause gastrointestinal side effects. Chronic iron excess, e.g. in primary and secondary hemochromatosis, may lead to hepatic fibrosis, diabetes mellitus and cardiac failure. Chronic intake of 50-100 mg Fe/day of highly bioavailable iron with home-brewed beer in sub-Saharan Africans lead to cirrhosis and diabetes. Applying a safety factor of 2 would lead to an upper safe level of 25-50 mg Fe/day for this endpoint of conventional iron toxicity. However, beyond this kind of damage iron is known to catalyze the generation of hydroxyl radicals from superoxide anions and to increase oxidative stress which, in turn, increases free iron concentration. This self-amplifying process may cause damage to lipid membranes and proteins, which relates radical generation and organ damage after ischemia-reperfusion events to available free iron in clinical and experimental settings. Correspondingly, epidemiological studies as well as observations in heterozygotes for hereditary hemochromatosis suggest that the risk of atherosclerosis and acute myocardial infarction is related to body iron stores, though there is conflicting epidemiological evidence as well. The most recent and best controlled studies, however, support the hypothesis that iron stores are related to cardiovascular risk. Iron-amplified oxidative stress may also increase DNA damage, oxidative activation of precancerogens and support tumor cell growth. This is supported by experimental, clinical and epidemiological observations. Due to these mechanisms high iron stores may present a health hazard. Though this has not been finally proven, available evidence strongly recommends not to increase iron intake beyond physiological requirements. To avoid iron deficiency symptoms, on the other hand, care must be taken to meet recommended daily intake. Copyright (C) 2001 S. Karger AG, Basel.
...more
View all episodesView all episodes
Download on the App Store

Medizin - Open Access LMU - Teil 12/22By Ludwig-Maximilians-Universität München


More shows like Medizin - Open Access LMU - Teil 12/22

View all
Center for Advanced Studies (CAS) Research Focus Evolutionary Biology (LMU) - HD by Center for Advanced Studies (CAS)

Center for Advanced Studies (CAS) Research Focus Evolutionary Biology (LMU) - HD

0 Listeners

Hegel lectures by Robert Brandom, LMU Munich by Robert Brandom, Axel Hutter

Hegel lectures by Robert Brandom, LMU Munich

6 Listeners

MCMP – Philosophy of Science by MCMP Team

MCMP – Philosophy of Science

1 Listeners

MCMP – Epistemology by MCMP Team

MCMP – Epistemology

0 Listeners

MCMP – Mathematical Philosophy (Archive 2011/12) by MCMP Team

MCMP – Mathematical Philosophy (Archive 2011/12)

6 Listeners

Sommerfeld Theory Colloquium (ASC) by Michael Haack

Sommerfeld Theory Colloquium (ASC)

2 Listeners

Theoretical Physics Schools (ASC) by The Arnold Sommerfeld Center for Theoretical Physics (ASC)

Theoretical Physics Schools (ASC)

2 Listeners

MCMP – Philosophy of Mind by MCMP Team

MCMP – Philosophy of Mind

0 Listeners

Women Thinkers in Antiquity and the Middle Ages - SD by Peter Adamson

Women Thinkers in Antiquity and the Middle Ages - SD

0 Listeners

NANO-BIO-PHYSICS SYMPOSIUM 06.09.2019 Day 1 by Ludwig-Maximilians-Universität München

NANO-BIO-PHYSICS SYMPOSIUM 06.09.2019 Day 1

0 Listeners