Dr. Steven Wangen shares how Irritable Bowel Syndrome (IBS) can cause iron deficiency and anemia, along with steps to take. Learn more about what can cause IBS, including gluten intolerance, here.
Many patients who have digestive problems are also anemic due to low iron or low vitamin B12 levels. This problem causes fatigue, so it should be of interest to many people. Being anemic and having IBS is not unusual and there is a logical reason for it. First we’ll discuss anemia and then how it relates to IBS and digestive problems.
What is anemia?
Anemia is a common blood disorder that is a decrease in the number of red blood cells (RBCs) and/or poorly formed red blood cells. These are the cells in your blood that carry oxygen. If you are anemic, then you will be tired because you are not delivering as much oxygen to your body as someone who is not anemic.
There are many different types of anemia, but the most common are due to iron deficiency or vitamin B12 deficiency. Iron deficiency anemia will show up on your complete blood count (CBC) as a low RBC count, low hematocrit (Htc), and/or low hemoglobin (Hgb). Vitamin B12 deficiency anemia typically shows up as an increase in the size of the red blood cells. On your CBC it is noted as the MCV.
How to catch low iron before you become anemic:
Iron is stored in the body in a protein form called ferritin. Ferritin levels can be measured with a simple blood test. Ferritin decreases long before iron deficiency anemia is apparent on a complete blood count. Therefore you can often prevent iron deficiency anemia by monitoring your ferritin level.
It can take several months of iron supplementation to rebuild iron stores. If you are anemic and you take iron only long enough to correct the anemia, you likely have not built up your iron stores enough to last for very long. Then you are much more likely to become anemic again in the near future, which of course will cause you to be tired. This is another good reason to check your ferritin level.
What is borderline anemia?
It is not unusual for people to report that they have been told that they are borderline anemic. In most cases, they were not told to take iron. What you should know is that borderline anemia is not a technical term. You either are anemic or you are not anemic. If you have been told that you are borderline anemic, then you are probably anemic.
Correcting this problem will help you to feel much better. If you are borderline anemic and it is due to an iron deficiency, then your iron stores will be very low. So have your ferritin checked.
What about vitamin B12?
If your anemia is due to a B12 deficiency, then taking B12 will solve your problem. Your doctor may prescribe B12 injections, which will improve the treatment and vastly increase the amount of B12 getting into your body. Vitamin B12 is also stored in the body, but its stores are unfortunately not so easy to measure.
What does this have to do with IBS?
The important question underlying anemia is “Why do you have low iron or B12 levels?” The answer may be that you don’t absorb them well. People with IBS and related digestive problems often have a problem absorbing nutrients. This is particularly obvious with diarrhea, which is clearly a malabsorption issue.
Article Courtesy: Dr. Stephen Wangen
Founder of the Center for Food Allergies and the IBS Treatment Center
photos courtesy of IBS Treatment Center
I'm disappointed that the article seems to suggest that IBS causes anemia. If anemia is present, further testing is required. It's a symptom, not a diagnosis.
It seems very likely that the patient's "IBS" is something else entirely, like celiac disease.
Tracey Burke says
I have iBS and i have lost weight. I have also been told i have low iron levels and my doctor prescribed iron tablets, but i had a baad reaction to the iron talbets before.. I don't seem to be getting an straight answer from the doctor as to what is causing my weight loss or why i have low iron levels. all my other blood test are normal. I am so frustrated
Hi Tracy my boyfriend is in the same boat we’ve been dealing with this for 2 years and no one can give us any answers. If you have any updates please let us know.
sandy bennett says
Has anyone suggested to you about having a colonoscopy?
I have ibs and now low iron levels and the 1st thing my Dr asked was have I had a recent colonoscopy
Hope you get some answers
What did the Colonoscopy tell you?
I was diagnosed with iron deficiency anaemia for the first time in my life out of the blue in the beginning of this year and was able to restore my hemoglobin to the normal range but the ferritin wouldn’t increase past the 3o’s (5 months of oral therapy) then only recently
My doctor put me off the oral iron tablets and got Iron infusions (i had 3 in total)
This is definitely not treating the cause but maybe talk to your hematologist about getting infusions (you’ll maybe need 1-3) ,that way you could feel much better faster and avoid the adverse effects of oral tablets on the gut
While your gastroenterologist figures out what you have (you should also ask for h pylori testing )
I hope you feel better soon
Stephanie Juarez says
Hi! Im currently going thru the same
Issue. I had a colonoscopy done, endoscopy, ct scans, ultrasound and everything has come out normal. Now out of the blue they told me i have iron deficiency anemia (3% saturation with 5 FERRITIN) theyre starting me with iron transfusion and also an oncologist to rule out any cancer (all my lab work has come back normal too) i cant help but think the worst. Did y’all ever receive a diagnose on this?
K.C. Cornwell says
Wishing you healing.
But, what if the patient tests negative for Celiac?
Maybe you should also talk to your doctor about the possibility of having crohn's disease, which has symptoms very similar to ibs. one of the differentiators is weight loss.
for those unable to take iron tablets, i've found a great iron supplement called active iron. it's very gentle on the stomach.
Hi Tracy, you may want to be checked for SIBO or bad gut dysbiosis. These conditions can affect nutrient absorption. SIBO can occasionally lead to weight loss. It has also been suggested that overgrowth of some bacteria can deplete iron because they feed on it. You will likely need to see a functional medicine practitioner to check this as many doctors, including GI specialists, are not trained in this area. I was diagnosed with SIBO in 2017 after 9 months of IBS symptoms and a 20 lb weight loss. Endoscopy and colonoscopy were all normal. but stool testing (done by a functional medicine doctor) revealed very low pancreatic elastase levels suggesting that exocrine enzyme production in my pancrease was affected, also suggesting suboptimal function of the epithelium in my small intestine. Damaged/inflamed small intestine equals less nutrient absorption. This was reversed with treatment of my SIBO.
As for your iron supplement, have you tried Ferrous bisglycinate chelate? This is available over the counter, “Ferrochel” is one brand name found in some supplements. Research has shown it causes less side affects. Also try taking only every other day (search alternate day iron dosing on Google).
how come your blood test are normal if you said that you have iorn deficiency. Your blood test may show low HCT level which means youre anemic
Dr. David Abell says
IBS is, essentially, a diagnosis of exclusion. Cœliac disease is one of the commoner occult causes of iron deficiency anaemia, but slow GI bleeding must always be excluded.
I have IBS... It's been three months.. it's very depressing as I'm unable to get my symptoms in control.. I had severe weight loss and now I'm anemic. all the tests have been done and now it is confirmed that I have IBS. Having a pain, feeling nauseous and weak all the time has become worst with time. I had to move in with my parents and leave my job. The meds that I take can help sometimes but every other day is a bad day when I also have breathlessness! Not sure for how long I have to keep living like this! It's really depressing
James erikson says
Hey I'm the same as you but I've had it for over a year now. Honestly I'd consider looking into the fodmap diet and maybe even getting a nutritionist to help. It's definitely helped me although it does take a lot of elimination and finding what your triggers are. I wish you the best tho!