When you need more iron, a mineral essential for making hemoglobin and carrying oxygen in your blood. Also known as ferrous iron, it's not just about popping any pill—different forms affect your body in very different ways. If you're low on iron, whether from heavy periods, pregnancy, or poor diet, the kind you take matters just as much as the dose. Some forms cause stomach upset, others don’t absorb well, and some cost way more for no real benefit.
Take ferrous sulfate, the most common and cheapest form of iron supplement. Also known as iron(II) sulfate, it’s what doctors often start with because it’s effective and widely available. But it’s also the one most likely to give you constipation, nausea, or dark stools. Then there’s ferrous fumarate, a form with more elemental iron per milligram, often better tolerated. It’s pricier, but if your stomach can’t handle sulfate, this might be your sweet spot. And don’t forget ferrous gluconate, a gentler option with less iron per pill, ideal for sensitive systems. It’s slower to build up your levels, but easier on your gut. Then there’s heme iron polypeptide—found in animal sources—which absorbs better without the side effects, but costs a lot more and isn’t always easy to find.
What you’re really comparing isn’t just price or brand—it’s how your body reacts. Absorption depends on whether you take it on an empty stomach or with food, whether you’re also taking calcium or antacids, and even how much vitamin C you get with it. Some people do fine with a daily low-dose tablet. Others need a slow-release version to avoid nausea. And if you’ve tried one form and it made you feel worse, that doesn’t mean iron doesn’t work for you—it just means you haven’t found the right one yet.
Below, you’ll find real comparisons between the most common iron supplements—what they cost, how they feel, how well they work, and who they’re best for. No fluff. Just clear, side-by-side details to help you pick the one that actually fits your life, not just your prescription.
