Recently I was talking to a good friend about vitamin and mineral supplementation. The discussion brought up Iron being blocked by Calcium. She brought up a fact that I never even heard before. So I started digging on the subject. Does Calcium block Iron absorption?
After reading a Journal Article published by the Department of Medicine at a University in Sweden, Iron absorption is decreased by almost 60% when eating or drinking a dairy product with an Iron rich food. This can be a big problem if you eat a good amount of dairy with your meals. Unfortunately I found a similar study done in the United States, published in the American Society for Clinical Nutrition, that had the same conclusion.
So how do you escape this problem? First, separate your Calcium supplement from your Iron. Second, if you are going to eat dairy try to eat it separate from foods that are high in iron. Another problem is that water has Calcium in it. So you have to drink distilled water with your Iron supplement to prevent interference.
According to NCBI, Calcium is in almost every form of drinking water. Except distilled. In the US, the average amount of Calcium in tap water varies from 1 to 135 ml/L. Bottled Spring water has a little higher findings, an average of about 208.3 ml/L. They even tested the Brita filter, but found that Calcium still appeared after filtration.
Another thing to think about is not eating dairy with red meat. One of your main sources of iron is from eating red meat. Sorry folks no more cheeseburgers. Well, everything in moderation. (I wonder if this is the reason why Jewish people can't have meat and cheese?)
Anemia might not be a problem for you, but think about how you feel. If you feel tired, lightheaded, weak, have headaches, disturbed sleep, or have brittle nails, you could be anemic. A simple change in diet might let your body function at a higher level. I can't give you an exact time frame for digestion of Iron before eating or drinking something with Calcium. My best suggestion is have your Iron first thing in the morning before getting ready. Hopefully the amount of time between getting ready and eating will give you body enough time. Even a little decrease in iron could throw your body off. So what do you have to lose? See how you feel when you keep Calcium separate from Iron.
University of Illinois - Foods high in Iron
LiveStrong- Does Coffee Block Iron Absorption