I'm sure lots of people already know this, but I thought I'd share this as I only really found out today and I'd been worrying about it.
Recent blood tests found that I had low iron levels, though I wasn't anaemic. I found this out over the phone from a doctor who basically said 'so we'll HAVE to put you on supplements'. This two days ago, and it wasn't the doctor I've been regularly seeing. I had an appointment today with the doctor I have been seeing (about gastro issues, which I think are on the mend) and I was all in a flap about low iron levels. And she said
"You're female and under 40; practically all women under 40 who have periods have low iron levels, we just don't usually find out because they're not actually anaemic, and the usual blood tests just check for anaemia. We don't even bother investigating the cause in these circumstances; we assume that it's related to loss of menstrual blood and a diet that's not quite high enough in iron".
So - if you're told you have low iron levels and you're female and still having periods: DON'T PANIC This doctor actually hasn't even put me on iron supplements (which I was worried about as they can screw up your stomach!); she said just to up the iron in my diet (having established that there hasn't been much iron in it really), increase vitamin C consumption and reduce caffeine consumption, and that I could take some over the counter supplements if I wanted. The main remedy is going on the pill to regulate my periods. Mine are heavy, but she says even if you have 'not especially heavy' periods, you can still have low iron as a result of periods. She says she doesn't think I need to be tested again for a couple of months and she's not concerned at all.