In order to absorb and use iron, our bodies need other essential nutrients. Here’s how I think of it:

Iron absorption

Some nutrients, like vitamin C, help you absorb iron better. But, once it’s absorbed, your body also needs to be able to use that iron, which might mean boosting some other nutrients.

An analogy: iron as flour

Think about cooking and baking. If you have lots of all the ingredients, you can make many things. Think of iron as your body’s flour. If your kitchen is well stocked (you are healthy), you have a lot of flour (iron), you could make pancakes (hemoglobin), muffins (hair growth), pies (platelets). If you start to run low on flour (iron), your body will prioritize the most important thing (pancakes!).

If you get an iron infusion, that’s like buying a 25 pound (12kg) bag of flour–you can make infinite pancakes, so you start cooking them up like crazy (pumping out hemoglobin) but then suddenly you run out of eggs (vitamin B12)–that’s the end of the pancake making for you! Eggs are “necessary” for flour use (in pancakes), and in your body vitamin B12 and folate are necessary for iron use, so even though your infusion may boost iron levels, you also meed the other “ingredients” to use that iron!