Q&A 016 · Low Hemoglobin in Men

⏱ 10 min read

Dr. Hayes Q&A · No. 016

By Eleanor Hayes, M.D. · Hospitalist

The Question

“I’m 61. My checkup showed a hemoglobin of 11.8, and my doctor said it was a little low and that I should try some iron. I feel completely fine. I thought anemia was something that happened to women. Do men even get this? Is it anything to worry about?”

— A reader in Georgia

The Short Answer

Yes, men get anemia, and when they do, the rule is stricter than it is for women. A woman of reproductive age has a built-in explanation for low iron. A man does not. So a low hemoglobin in men is treated as a question that needs an answer, not a number that needs a supplement. The question is where the blood went, and the most common answer is the gut, quietly, without anyone seeing it. “Try some iron” is not wrong as a treatment. It is wrong as a first step, because iron can raise the number while the cause keeps bleeding. And your table contains two details that make the question more urgent, not less: the ibuprofen you take every day, and the ice you have started chewing. Neither is a habit. Both are clues. The rest of this article is what to do with them.

Why Low Hemoglobin in Men Always Needs a Reason

The line. Hemoglobin is the protein inside red blood cells that carries oxygen. The World Health Organization defines anemia in men as a hemoglobin below 13 g/dL, and in its 2024 update it kept that cutoff while noting the data might support a higher one, around 13.5. Your 11.8 is below either line. It is not “a little low.” It is anemia, and “a little” is the word that lets it get ignored.

Why feeling fine is not reassurance. Anemia that arrives slowly is anemia the body adapts to. When hemoglobin drifts from 14.5 to 11.8 over months, the heart beats a little faster, breathing adjusts, and the person learns to live with less oxygen without ever noticing the trade. In Hospital 366 Case No. 29, a woman with COPD sat in an ambulance at an oxygen saturation of 85 percent and said this was how she always was. The same mechanism is at work here. Your table says you feel fine, and it also says you get winded on stairs. Those are the same sentence. The second one is the adaptation reaching its limit. And the 11.8 is a photograph. If last year’s checkup said 14.5, this is an urgent film. If it said 12.0, it is a different story. Finding last year’s number is the first thing to do.

Where the blood went. Anemia has three causes: the body makes too few red cells, loses too many, or destroys them too fast. In a man past 50, the most common is loss, and the most common loss is one you cannot see, a slow leak somewhere in the digestive tract. A few milliliters a day, not enough to change the color of the stool, is enough to empty the body’s iron stores over months and then pull the hemoglobin down behind them.

The ibuprofen. This is where the daily tablet for the knee enters. Ibuprofen and its relatives, the NSAIDs, suppress the prostaglandins that protect the lining of the stomach and small intestine. Taken every day, they create small erosions that bleed quietly. A 2025 meta-analysis of 25 studies found that ibuprofen roughly doubles the odds of gastrointestinal bleeding, and it is actually the gentlest of the non-selective NSAIDs on that list. A knee that hurts, a pill that helps, and a gut that pays for it in small daily installments is one of the most ordinary stories in medicine. That ordinariness is the danger. It makes the ibuprofen feel like the whole explanation.

The rule that does not bend. It is not the whole explanation, and this is the part I most want you to hear. In a man over 50 with iron deficiency anemia, the thing that must be ruled out is colon cancer. A tumor on the right side of the colon can bleed for a long time without any visible sign, and anemia is often its first and only signal. That is why the American Gastroenterological Association strongly recommends upper endoscopy and colonoscopy for every man with iron deficiency anemia, symptoms or no symptoms. The guideline does not carve out an exception for men who take NSAIDs, and the reason is in the numbers. When men and postmenopausal women with iron deficiency anemia are scoped, about one in eleven turns out to have a cancer in the lower gut, and about one in fifty in the upper. “The ibuprofen is probably the cause” and “it is not cancer” are two different sentences, and only a scope can write the second one. This is also why “try some iron” first is the wrong order. Iron will raise the hemoglobin. The number will look better. And the leak will still be there, now without the alarm that was pointing at it.

The ice. Now the last line of your table. Chewing ice most days. Compulsive ice craving has a name, pagophagia, and it is one of the oldest clinical signs of iron deficiency. In one study, 56 percent of people with iron deficiency anemia reported it, against 4 percent of people without. Nobody fully understands why, though one theory is that the cold briefly improves blood flow to the brain and gives an iron-starved mind a lift. What is well documented is that the craving often disappears within days of iron replacement, sometimes before the hemoglobin has moved at all. Patients never report it. They call it a habit, as you did. It only comes out when a doctor asks. Consider yourself asked.

The other branches. Everything above assumes your anemia is from iron, and the next two numbers on your report decide whether that assumption holds. Ferritin measures stored iron. The AGA now uses a cutoff of 45 ng/mL rather than the old 15, because the lower line missed too many real cases. MCV measures the size of the red cells. Low ferritin and small cells mean iron deficiency, and you are on the road described above. Normal ferritin with large cells points elsewhere: vitamin B12, folate, thyroid, and alcohol, which swells red cells even at modest intake. Two drinks a few times a week will not cause anemia by itself, but it can nudge the cell size, and that gets its own article in Q&A 082. Normal ferritin with normal-sized cells sends me to the kidney, which makes the hormone that tells the marrow to build red cells, and the creatinine sitting next to it on your report, covered in Q&A 013.

The line that still holds. This is an article about not skipping a step, not about assuming the worst. Most men in your position turn out to have an NSAID-related leak, a benign polyp, or a stomach irritation, and the scope finds it and the fix is simple. But the ones who turn out to have more are the ones who cannot afford the shortcut. Whether an 11.8 is a nuisance or a warning is not settled by how you feel. It is settled by procedure, and the procedure is below.

What I See in the Hospital

Men arrive in the emergency room with a hemoglobin of 6 or 7. Most have passed black stools for a few days, gotten dizzy, and fallen. When I open the chart, there is a checkup from a year or two earlier with a hemoglobin in the 11s and a note that says “recommend iron supplementation.” Between that note and this bed, there was no endoscopy. The iron may even have worked for a while. That is the cruelty of it. The number improved, the concern faded, and the bleeding went on underneath.

I see the other version too. A man whose 11.8 bought him a colonoscopy he did not want, which found an early cancer that came out in a single operation. For him, anemia was not the disease. It was the alarm that went off in time.

The reason a man’s anemia has a rule is simple. With no built-in explanation, an explanation has to be found, and the search has to start with the worst possibility, not the most likely one. In the first article of this category I wrote that a single value is a photograph and a trend is the film. Hemoglobin is the one value where I would add a third thing. Sometimes the photograph is of a door, and you have to open it.

Plain-Language Reference

What to Actually Do

· Before starting iron, ask for ferritin, MCV, and a stool occult blood test. The order matters. Iron started first erases the evidence.
· If ferritin is low, ask for a referral for upper endoscopy and colonoscopy, even with no symptoms. That is the standard of care for a man with iron deficiency anemia, not an excess of caution.
· Put the daily ibuprofen on the table with your doctor and talk through alternatives for the knee: acetaminophen within its limits, a topical anti-inflammatory, physical therapy. Stopping it does not cancel the scope. It only removes one suspect.
· Dig out last year’s hemoglobin and put it next to this one. A drop of two or three points in a year is a different conversation from a number that has sat at 12 for a decade.
· Do not wait for the scheduled recheck if you notice black or tarry stools, new dizziness, a pounding heartbeat, or the stairs getting harder week to week. Those are the leak speeding up.

This article is for general information only and does not constitute medical advice, and reading it creates no provider-patient relationship. How a hemoglobin of 11.8 should be interpreted depends on individual factors this article cannot assess, and nothing here replaces the judgment of your physician or a gastroenterologist. Anemia in a man can be the first sign of gastrointestinal bleeding or cancer, and it should be evaluated rather than treated blindly. If low hemoglobin comes with black or bloody stools, vomiting blood, fainting, chest pain, or rapidly worsening shortness of breath, seek emergency care immediately. Do not stop or change a prescribed medication without talking to the physician who prescribed it.

Take care of yourself. Nobody else will do it for you.
— Eleanor Hayes, M.D.