Does OK hemoglobin make a low level of iron in blood OK?

[nomadreid]

TL;DR Summary

What meaning does a level of iron lower than the healthy range combined with the hemoglobin levels in the middle of the accepted range have?

Suppose a blood test shows a value of 41 milligrams per deciliter, with a healthy range between 65-175, yet the hemoglobin levels in the same blood test are perfectly normal, as well as are other indicators in the blood test. A doctor explained that one would not need to be worried about the iron level (so no iron supplements etc.) because of the hemoglobin level. Could someone elaborate on why this could be so (or why not), and under what conditions? [If age and/or sex are factors, the person involved is a senior citizen, male.]

(Caveat: I understand that this is a broad question without the full set of information available to a doctor, and any answer here does not constitute medical advice.)

 

[jim mcnamara]

Consider: the major use of iron is the synthesis of hemoglobin. So, hemoglobin is the really major iron sink in mammals. Humans are mammals. Hemoglobin levels reflect an organism's overall iron levels.

Overiew of homeostasis:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5198508/
Hepcidin causes iron sequestering which lowers serum iron levels -- example: during the response to inflammation from infections - a cold, a GI tract infection, etc.

For hepcidin see:
https://en.wikipedia.org/wiki/Hepcidin

 

[nomadreid]

Thank you, Jim McNamara. That was very helpful.

 

[bhobba]

Jim is right. The inflammation may be caused by an autoimmune disease. It happened to me. They hunted around, even did a colonoscopy (I was about 50 so the guidelines were you get one anyway). Nothing - except also a high ESR (a measure of inflammation). But one doctor noticed I had a huge blob of psoriasis on my forehead and the diagnoses was immediate - psoriatic arthritis which was confirmed by a Rheumatologist, who examined me and checked the blood work. I would see a Rheumatologist taking along blood tests for inflammation, such as ESR. They will possibly order even more to confirm a diagnoses.

Thanks
Bill

 

[nomadreid]

Thanks for the suggestion, Bill aka bhobba. However, the blood test which showed the low level of iron included also tests for infection, and those results were well within the norms. A visit to a rheumatologist, with corresponding blood tests, did in fact take place a few months earlier and came up empty. No symptoms since that visit indicating inflammation have been noticed. The GP considers that the low iron level does not warrant further tests, another indication that there may be factors that are not pathological.

 

[berkeman]

Thread closed temporarily for Moderation...

 

[jim mcnamara]

back open. Please consider that we do not support commenting on treatments or responses. We can comment on known science, not medical opinion.

 

[Fra]

The GP considers that the low iron level does not warrant further tests, another indication that there may be factors that are not pathological.

Having nothing to do with your specific case but generel conclusions like this makes good sense, because "normal" ranges of ANY physiological or medical test/score are based on population statistics. One can never make certain inferences of individual cases from statistics. But statistics is still a rational tool for motivating when further tests or examinations is required. This is also the case for research where you use random subjects, some subjects simply have a slightly "abnormal" physiology (but this does not imply they are sick or have any problems), it just means they are outlies are does not fit into the statistical or average model of human physiology and medicin.

But if this is made and there are not other symptoms, then it might very well be so that this certainl individual simply has a "deviant" physiology. This does not imply pathology, it just means we are all slightly different. In these case.

/Fredrik

 

[nomadreid]

Very good observation, Fredrik aka Fra. Thank you.

 

[jrmichler]

This is a topic of interest to endurance athletes, and is discussed in The Lore of Running, Fourth Edition, by Timothy D. Noakes, MD, on pages 913-917. A quote from page 915 summarizes the entire section:

In the absence of established anemia, shown by low blood hemoglobin levels, low serum ferritin levels can probably be ignored, as they do not affect athletic performance (Garza et al. 1997).

 

[nomadreid]

Interesting and very relevant. Thank you, jrmichler