Your ferritin came back. Now what?

You had blood drawn. Somewhere on the report is a line called ferritin, and next to it, a number. If nobody said anything about it, that's because it sat inside the reference range. Silence, though, isn't the same as safety. Here's what that number does, and doesn't, tell you.

One note before the numbers. They apply to men, and to women past menopause. Women who are still menstruating usually run low rather than high, for reasons this site covers.

What “normal” actually means

A lab’s reference range describes a population. It's built from the spread of results across apparently healthy people, roughly the middle 95 percent. That makes it useful for spotting the extremes. It isn't a treatment target, and it isn't the range where your body works best. Those are different questions, and the report doesn’t answer them.

For ferritin the flagged ceiling is generous. Many labs allow up to about 300 nanograms per milliliter, some higher, before your result draws a comment.

The risk data don’t wait for 300. In a study of 1,931 Finnish men published in Circulation in 1992, the men with ferritin above 200 had 2.2 times the risk of a heart attack in the years that followed. The numbers were small in absolute terms, 51 heart attacks across the whole study, and the doubling held up in every model they ran. Two hundred is simply where that study cut its data. It isn't where risk begins, and the curve climbs all the way through the range. Above 200 is still “normal” on most lab reports, which is the whole problem with reading a range as a verdict.

Iron overload is rust. Slow oxidation, from the inside, and the lab report files it under normal.

What one number can’t tell you

Ferritin mostly tracks stored iron, and it's the best single screen there is. But it isn't only an iron number. It also rises with inflammation and with liver disease, which is why one high reading isn't a diagnosis, and why it gets read alongside transferrin saturation and the rest of your picture. Neither reading is a reason to sit still. Accumulated iron responds to the steps below, and a number held up by inflammation isn't reassurance, it's a second thing worth chasing with the person who ordered the test.

P. D. Mangan has published peer-reviewed work on iron and aging. He is a coach, not a physician, and nothing on this page diagnoses you; what it gives you is the map, and better questions to bring.

Where the good range sits

Iron risk runs on a U-shaped curve: too little is harmful, and so is the high end of “normal.” Stored iron is reactive, and the body has no route for excreting the excess. The five-minute version is here. The target P. D. uses with his own clients is comfortably above anemia and under 100. That isn't where the lab draws its line. It's his read of where the evidence points, argued in full, with references, in the book’s protocol chapter.

Between 100 and 200 isn't an alarm. It's a project, and the four steps below are the whole of it. And if your result came back low, or flagged low, unloading iron isn't your project; that conversation belongs with the person who ordered the test.

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The whole loop, in four steps

Centers typically allow a donation every eight weeks, and they screen your eligibility every time. How often you should donate is case by case; the protocol chapter maps a schedule to your starting number.

Two words worth knowing

Hemochromatosis is hereditary iron overload, and it's the one part of this subject medicine already takes seriously. As the book puts it, doctors know all about it: untreated it can cause cancer, liver disease and early death, and it's hard to overlook, because straightforward lab tests and an examination find it. The iron levels involved are sky high, far above the range this page is about. That's the whole point of the argument here. Ordinary care handles the recognized disease. What it misses is the long stretch of “normal” underneath it. If your number came back very high, ask about hemochromatosis, and ask for transferrin saturation alongside it. Those are questions for the person who ordered the test.

Therapeutic phlebotomy is the medical version of what step 3 describes: blood removed on a doctor’s order, on a calibrated schedule, for someone with diagnosed iron overload. In the studies the book draws on, patients were bled periodically until ferritin reached “near-iron deficiency,” around 30. That's a different thing from walking into a blood bank, and it's your doctor’s to arrange, not yours. Giving blood is something a healthy person can simply choose to do. Therapeutic phlebotomy is ordered and supervised.

The part almost nobody says out loud

Blood donation is marketed as a gift to others, and it is. It's also the only real mechanism a man’s body has ever had for unloading iron. Women have one for decades, through menstruation; Jerome Sullivan proposed in The Lancet in 1981 that this may be one reason premenopausal women see so much less heart disease, a hypothesis P. D. has since published on himself. Donating gives you that mechanism, on your schedule, at no cost.

If donation isn't open to you, iron can still come down. The protocol chapter maps the options, with your doctor in the loop.

Now the honest part. Getting your iron right is worth doing, and on its own it will not make you lean, fit, and strong. Iron is one lever. The machine is body composition, strength, and the systems that keep them in place.

The full protocol chapter, with the numbers behind every step. Or the peer-reviewed paper.