One of the key pieces of evidence leading to the implication that iron causes heart disease is the differential incidence of heart disease between men and women. Men have far higher rates of heart disease, and they have much higher iron levels, since women lose iron via menstruation. When women cease menstruation at menopause, their risk of heart disease goes way up, and this is not due to hormones, as both of the pieces below note.
That’s the topic of two letters just published in JAMA Cardiology, one by Luca Mascitelli, M.D. and Mark Goldstein, M.D., the other by Virginia Mary Hayes, M.S., Ralph George DePalma, M.D., and Leo Zacharski, M.D., all of them experts on the relation between iron and health. I know a couple of these people, and Dr. Mascitelli kindly sent me these letters, which I’m publishing here because otherwise the public won’t get to see them due to a paywall.
Iron (ferritin) levels above the minimum serve no purpose; it’s merely storage. (Admittedly, if you lost a lot of blood, didn’t die from it, and had no medical care, you might return to health faster if you had more iron stores, but that’s about the only example I can think of where more iron might be better.) Basically, there’s no downside to keeping ferritin within a low normal range, and it could save you from a heart attack.
Premenopausal women have naturally low levels of iron, and this almost completely protects them from heart disease.
By the way, another possible explanation as to how lower iron decreases heart disease risk concerns microbes: iron allows them to grow, and they may cause heart disease.