Iron Deficiency Anemia and Digestive Disorders: Recognizing Underlying Causes and Treatment Challenges
Written by: Julia Zakrzewski, RD
Updated: May 21st, 2025
Iron is an essential nutrient that your body uses to create healthy red blood cells. It’s primarily absorbed in the small intestine, with most uptake occurring in the duodenum and jejunum sections.
However, if you have a digestive health condition, your small intestine may not absorb iron as efficiently. If precautionary steps are not taken, this could increase your risk of developing an iron deficiency or anemia.
Fortunately, an iron deficiency can be corrected through dietary changes—such as eating more iron-rich foods, starting a supplement, or, in advanced cases, receiving an iron transfusion.
Keep reading to learn about three digestive disorders that are high risk for iron deficiencies and what treatment challenges you may experience while trying to raise your iron levels.
1. Celiac Disease
Celiac disease is an autoimmune condition in which the small intestine is sensitive to gluten, a protein naturally found in wheat, barley, rye, and triticale-containing foods.
It’s estimated that celiac disease affects approximately 1% of the Canadian population, and people with this digestive condition must follow a strict gluten-free lifestyle to stay healthy. This includes dietary changes (avoiding gluten-containing foods) and limiting exposure to gluten-containing beauty and skin products as well as medications or supplements.
How Does it Impact Iron Absorption?
If someone with celiac disease eats gluten or is exposed to gluten, the villi in their small intestine (small projections that absorb nutrients) become damaged and can’t absorb iron.
The villi will heal after adhering to a gluten-free lifestyle, but it can take months to build back up your iron stores.
Treatment Challenges
Research suggests that some people with Celiac disease are more prone to experiencing low iron levels—even after following a gluten-free lifestyle. This might be caused by genetics, as some people are inherently predisposed to lower iron absorption rates. There’s also a possibility that people could go into “remission” by unintentionally eating gluten and re-damaging their villi.
It’s vital that you work with your specialist or family doctor to create a treatment plan that helps you maintain healthy iron levels, which may include dietary changes and starting a supplement.
2. Gastritis
Gastritis is inflammation of the stomach lining, which can be excruciating and significantly decrease one’s appetite and desire to eat.
It’s unclear what causes gastritis, but it can be a side effect of another health issue—commonly an H. Pylori infection.
Many people take medications to control stomach acid levels, antacids, and pain relievers to manage gastritis.
How Does it Impact Iron Absorption?
When the stomach lining is inflamed, it can’t efficiently absorb nutrients, which could increase the risk of iron deficiency over time.
Once your healthcare team understands your digestive health status (and rules out other potential conditions, like an infection), they can build a personalized plan to help you feel your best and maintain your iron stores.
Treatment Challenges
Nutrition guidelines for gastritis recommend limiting red meat in the diet, as it can be very hard on the digestive system. These foods are also rich in iron, making it harder to satisfy your daily intake without a supplement.
3. Crohn’s Disease
Crohn’s disease is an autoimmune condition and is a type of inflammatory bowel disease. People with this digestive health condition can experience painful bouts of inflammation anywhere along their digestive tract—but it commonly affects the small intestine.
If you have Crohn’s disease, you’ll need to work closely with a specialist to manage your symptoms and overall health.
How Does it Impact Iron Absorption?
While inflamed, the small intestine can’t properly absorb nutrients (including iron), which increases the risk of nutrient deficiencies. Crohn’s is also lifelong, and iron levels must be monitored indefinitely.
Treatment Challenges
Crohn’s condition can cause slow blood loss in the digestive tract, making it harder to replenish your iron stores. Also, some people can’t tolerate eating red meat as it’s difficult to digest, which is naturally rich in iron.
You may need to take an iron supplement to satisfy your nutritional needs.
Gastric Surgery and its Impact on Iron Uptake
Bariatric surgery (or gastric surgery) isn’t a health condition but alters your digestive tract’s ability to absorb iron.
People opt for weight loss surgery to manage obesity. It’s a life-changing decision that can only be medically considered if a person hasn’t successfully lost weight through lifestyle changes or medications first.
If you choose surgery, you can expect to wait several years until having your procedure (unless you visit a private clinic) because of long waits for operating rooms. During this time, you can learn about the recommended lifestyle and nutrition requirements post-surgery.
Weight loss surgery alone won’t be enough to maintain long-term results. To successfully lose weight (and keep it off), you must diligently follow your nutrition care plan, which includes taking supplements indefinitely to prevent nutrient deficiencies.
How Does it Impact Iron Absorption?
Many types of weight loss surgeries alter stomach size and intestine function. This significantly decreases the amount of food you can eat, which helps with weight loss, but it also limits the surface area that could absorb iron.
How to Prevent an Iron Deficiency
After gastric surgery, you must modify your diet, eat smaller portions more frequently, and take daily iron supplements.
To ensure a high absorption rate, your specialist will tell you what dose to take, which brand, and other relevant details, like when to take your supplement.
In Summary
Any type of digestive health condition can interfere with your body’s ability to absorb nutrients, including iron.
If you have a digestive condition mentioned in our article and are concerned about your iron levels, ask your doctor for a blood requisition to assess your levels.
If you have low iron levels, you can manage them immediately by modifying your diet, starting a supplement, or getting an iron transfusion (which is only necessary for critically low iron levels).
You may also want to meet with a dietitian to learn evidence-based strategies to manage your digestive health. Learn more iron deficiency symptoms, causes, risk factors and treatment options here.
This resource was made possible due to an unrestricted educational grant from Hemaforte.
References
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