If you live with Crohn’s disease or ulcerative colitis, you are probably familiar with the gastrointestinal (GI) symptoms that inflammatory bowel disease (IBD) can cause.
In addition to gastrointestinal symptoms, people with IBD usually suffer from nutritional deficiencies, the three most common being iron deficiency, vitamin D deficiency, and vitamin B12 deficiency.
I’ve been living with Crohn’s disease for about 6 years now, so I understand firsthand what it’s like to live with nutritional deficiencies. It can certainly be difficult to get these levels up to the ideal range.
It wasn’t until I went to medical school that I really understood why these impairments happen and what to do about them.
Frequent toilet visits, loss of appetite, and inflammation common in IBD can all contribute to malnutrition and decreased nutrient absorption.
Some people with these vitamin and mineral deficiencies have no symptoms, while others may experience symptoms – such as fatigue and cognitive problems – and report a decrease in their quality of life.
Persistent nutritional deficiencies can also present certain dangers, which is why it’s important to identify any deficiencies you might have and treat them appropriately.
The body uses iron to make a protein called hemoglobin, which allows red blood cells to carry oxygen from the lungs to the rest of the body. The upper parts of the small intestine absorb iron.
The best sources of iron are found in meat, especially red meat. There is also iron in plants, like leafy greens, but this form of iron is much more difficult for the body to absorb. This is why vegetarians are at
Anemia, or low hemoglobin level, occurs when the body cannot produce enough healthy red blood cells. Iron deficiency anemia is very common in people with IBD, with an estimated
This is possible to have iron deficiency without anemia.
Iron deficiency can occur with:
- blood loss (usually gastrointestinal or menstrual)
- decreased absorption (often due to inflammation of the small intestine)
- decreased dietary iron intake (vegetarian / vegan diets)
You could have chronic blood loss without even realizing it. Sometimes you can’t see the blood in your stool without using a microscope.
The signs and symptoms of iron deficiency anemia include:
- shortness of breath
- difficulty concentrating
- restless legs
- pale skin
- rapid heartbeat
- pica, a condition in which individuals crave items that are not food, such as ice or dirt
My sister always notices when I am anemic because my face is colorless and my lips are getting particularly pale. I also notice that I get a lot more exhausted going up the stairs and don’t have the stamina or stamina to exercise as I normally can.
Treatment includes replenishing your iron stores orally or intravenously. Some people with IBD tolerate oral iron supplements well, and others have exacerbated gastrointestinal symptoms with oral iron, requiring the use of intravenous iron.
However, if the anemia is severe enough, a blood transfusion may be needed to bring hemoglobin levels back to a healthy level.
Over the years, iron infusions, in addition to eating lots of iron-rich foods, have helped maintain my iron levels and improve anemia.
Vitamin D is a steroid hormone that our body produces from sunlight on our skin. It is also found in some foods.
It can be difficult to get enough vitamin D from the sun alone, which is why many people need vitamin D supplements in addition to consuming foods rich in vitamin D.
Some of the best food sources of vitamin D include:
- Cod liver oil
- dairy products
People with IBD have a higher risk of developing vitamin D deficiency due to malnutrition and malabsorption.
Low levels of vitamin D are associated with an increased risk of hospitalizations and surgeries in people with IBD. On the other hand, higher levels of vitamin D are associated with a decreased risk of Clostridioides difficile (C. diff) infection, for which those of us with IBD are also at increased risk.
Most people with vitamin D deficiency have no symptoms.
Long-term vitamin D and calcium deficiencies increase the chances of developing osteoporosis or decreased bone mineral density. This increases the risk of broken bones.
Vitamin D deficiency has also been linked to certain cancers and autoimmune diseases. A deficiency is usually treated with oral vitamin D supplements.
My vitamin D levels are almost always low, so I try to be consistent about taking vitamin D supplements and being in the sun. It’s hard now that I’m a resident doctor and no longer a lifeguard!
I can’t say I’m noticing any symptoms of this deficiency, but I do know that it’s important for both my Crohn’s disease and my overall health to maintain adequate levels of vitamin D.
Vitamin B12 is an essential vitamin for the healthy production of red blood cells, the synthesis of DNA and the proper functioning of the central nervous system.
This vitamin is found naturally in animal products, such as meat, fish, poultry, eggs and dairy products. It is also fortified in many breads and cereals.
People who follow a vegan or vegetarian diet may not get enough vitamin B12 from diet alone and may require supplementation.
Vitamin B12 is absorbed in the terminal ileum, which is the end of the small intestine just before connecting to the colon. This area is also the most common location for Crohn’s inflammation.
With active inflammation in this area, it is much more difficult to absorb vitamin B12 from food. If you’ve had surgery in this part of your intestines, you may also have difficulty absorbing vitamin B12.
Other causes of vitamin B12 deficiency in people with IBD include gastritis (inflammation of the stomach) and bacterial overgrowth in the small intestine.
Vitamin B12 deficiency can be quite serious and over time cause:
- cognitive slowdown
- difficulty walking
- peripheral neuropathy (more in the legs than in the arms)
Treatment for vitamin B12 deficiency includes oral, sublingual, or intramuscular replacement. Intramuscular injections of B12 may be necessary in case of active Crohn’s disease (terminal ileitis) or after surgery if the terminal ileum has been removed.
My vitamin B12 levels are low, but I can’t say I’m having symptoms of it. I know my terminal ileum is affected by my Crohn’s disease, so I take oral vitamin B12 supplements to help maintain my levels because I am not getting enough from food alone.
Nutritional deficiencies are extremely common in people with Crohn’s disease and ulcerative colitis. These deficiencies can cause bothersome symptoms, affect quality of life, and even lead to potentially dangerous complications if left untreated.
Personally, I feel better when my vitamin levels, especially iron, are in a healthy range.
Be sure to discuss your particular risks of developing nutritional deficiencies with a healthcare professional and make sure they are being treated appropriately.
Jamie Horrigan, MD, is a passionate advocate for Crohn’s disease who truly believes in the power of nutrition and lifestyle. When she’s not taking care of patients in the hospital, you can find her in the kitchen. For awesome gluten-free, paleo, AIP and SCD recipes, lifestyle tips and to follow her journey, be sure to follow her. Blog, Instagram, Pinterest, Facebook, and Twitter.