My last post (“I’ve Come To Suck Your Blood…”) was about my experience giving blood and some helpful tips on what to do before and after donating. Today’s post is about iron, which is a necessary component of healthy blood.
To start, here’s a bit of science for you. On a molecular level, a red blood cell is made of hemoglobin which consists of 4 chains of amino acids called “globulin chains – alpha and beta.” Each chain contains a “heme group” containing iron attached at the center (pictured in red). It is here that oxygen can bind forming oxyhemoglobin. Carrying oxygen is iron’s main function. I could keep going but I won’t bore you with more except that blood is made in red bone marrow which is found in the flat bones of adults, such as the scapula (the shoulder wing), the ilium (the top portion of the hip bone) and the sternum. To help the red bone marrow inside these bones make good blood rich in iron foods rich in iron should be consumed regularly, or iron supplements can be taken if instructed by a doctor or nutritionist/Registered Dietitian. If iron gets low in the blood, it can’t carry enough oxygen.
The night before I gave blood we had two good friends over for dinner, one of which gave blood with me. I did a little research for our meal and found some interesting information about iron in food.
- Iron comes from both plant and animal sources.
- Animal sources are considered “heme iron” and plant sources are considered “nonheme iron.” The distinguishing factor has to do with the way the iron is carried in the food. For example, heme iron in animal sources comes from the animal tissue with similar hemoglobin to humans.
- Unfortunately, iron is not easy to absorb and many factors affect absorption. These factors can include how much iron is already in your system, other nutrients that can enhance or cancel out the iron ingested, and what form (heme or nonheme) is consumed.
- Heme iron is more easily absorbed but nonheme iron can be absorbed more easily if consumed with vitamin C. Also, for carnivores, the absorption of nonheme iron can be boosted if eaten with some heme iron.
- Cooking in an iron skillet helps iron absorption (I found this most interesting).
According to the American Dietetic Association’s Complete Food and Nutrition Guide (which you can find on my Book List) foods rich in heme iron include (starting with the greatest number of iron): beef liver (I know), sirloin, ground beef, skinless dark and white meat chicken, pork and salmon. Sources of nonheme iron include: fortified breakfast cereal, pumpkin seeds, soybean nuts, spinach, red kidney beans, prunes and prune juice, lima beans, whole-wheat bread, eggs, etc. The list goes on.
There you have it. Everything you may or may not have wanted to know about iron. Feel free to ask any questions. Oh, and if you’re interested, I roasted a chicken and paired it with green beans and red potatoes cooked with caramelized onions. For dessert we ate mango popsicles. Happy Monday everyone!