Iron through your cycle: why you feel it, and what helps
Menstruation increases iron loss, which can leave you tired and foggy. Here's how much iron you need, which foods help, and how to absorb more of it.
Why iron matters more around your period
Every period you lose blood — and with it, iron. That’s a normal part of the menstrual cycle, but over time it can nudge you toward low iron stores, especially if your periods are heavy. Low iron shows up as fatigue, breathlessness on the stairs, poor concentration, and that “running on empty” feeling many people notice in the days around menstruation.
How much iron do you need?
Menstruating adults need roughly 18 mg of iron a day — noticeably more than the ~8 mg non-menstruating adults need. Needs rise if your periods are heavy. You don’t need to hit the number perfectly every day; what matters is a steady pattern over the weeks.
Foods that help
There are two kinds of dietary iron:
- Heme iron (from meat, poultry, fish) is absorbed well.
- Non-heme iron (from beans, lentils, tofu, dark leafy greens, fortified grains) is absorbed less efficiently — but you can boost it.
Absorb more of what you eat
Absorption is where most people gain ground:
- Pair non-heme iron with vitamin C — a squeeze of lemon, peppers, or fruit alongside your lentils meaningfully increases uptake.
- Separate iron from tea and coffee — the polyphenols in them inhibit absorption, so give it an hour either side.
- Don’t take calcium supplements at the same time as your main iron-rich meal.
What Fawna does
Fawna surfaces iron as a key nutrient around menstruation and helps you notice patterns without turning it into a chore. It won’t inflate your calorie target for your period — the honest answer is that your energy needs don’t meaningfully change across the cycle. It adapts the plan, not the number.
FAQ
Should I take an iron supplement? If you suspect low iron — persistent fatigue, heavy periods — ask your doctor for a ferritin test before supplementing. More isn’t automatically better.
Does coffee really block iron? Yes, meaningfully, if you drink it with an iron-rich meal. Shift it by an hour and you keep both.
References
- Harvey LJ et al. Br J Nutrition (2005)
- Hallberg L & Hulthén L. Am J Clin Nutrition (2000)
- NICE CKS — Heavy menstrual bleeding (2023)
General information, not medical advice. Reviewed for accuracy; always consult a qualified professional about your health.
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