Giraffe
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mujuro said:https://raypeatforum.com/forums/posts/96928/ [The lead skeptic on Peatarian posted a number of studies showing that almost nothing impacts absorption of heme-iron, that which is found in red meat.
Calcium and Iron Interactions
Inhibition of haem-iron absorption in man by calcium
http://journals.cambridge.org/action/di ... 4593000546
The present studies were designed to examine whether Ca interfered with the enhancing effect of meat on haem-Fe absorption. We found that the inhibition was the same whether biosynthetically radio-Fe-labelled haemoglobin was given in meals with or without meat. The haem-Fe absorption ratio with: without added Ca was 0.59 (SE 0.07) when Ca was added to a hamburger meal, and 0.052 (se 0.03) when added to a wheat roll. These values were not significantly different (t 0.95; P = 0.35). The inhibition of haem-Fe absorption by Ca is, thus, a direct effect on the absorption of haem-Fe and not an indirect counteracting effect of the well-known enhancing effect of meat on haem-Fe absorption. Control studies were conducted to ensure that haem-Fe had not been degraded to non-haem-Fe during preparation of the foods. Since Ca inhibits the absorption of haem- and non-haem-Fe to the same extent, the present results strongly suggest that Ca interferes with the transport of Fe through the mucosal cell, and at a late stage, is common for haem and non-haem-Fe transport. The observations that Ca strongly interferes with the absorption of both haem- and non-haem-Fe have important nutritional implications.
Calcium: effect of different amounts on nonheme- and heme-iron absorption in humans.
http://ajcn.nutrition.org/content/53/1/112.short
http://ajcn.nutrition.org/content/53/1/ ... l.pdf+html
Calcium also had a direct dose-related inhibiting effect on iron absorption, noted by adding calcium to the rolls after they had been baked instead of to the dough. Iron absorption was reduced by 50-60% at doses of 300-600 mg Ca. Giving 165 mg Ca as milk, cheese, or calcium chloride reduced absorption by 50-60%. The same amount of calcium also significantly reduced heme-iron absorption, suggesting that the effect of calcium is related to the mucosal transfer of iron.
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