I read slo fe is more gentle and I know it is as I take it. However, I take my thyroid in the morning which is ALSO when they recommend taking iron, on an empty stomach with vitamin C. If I cannot take iron and thyroid together as the thyroid will not be aborbed then WHEN can I take the iron (as food interferes with the absorption of iron) as does nedxium- which I take. How many hours is slo fe in the tummy? also, I take chromium and magnesium and- how does the iron fit in- does it hinder the absorption of either or both of those. Still, I need to know how long slo fe is in my tummy.