Importance of Nutritional Screening in IBD

Living with Crohn's disease or ulcerative colitis involves navigating unpredictable GI discomfort. This often ranges from cramping and urgency to fatigue that lingers well beyond a flare. Alongside these day-to-day symptoms, nutrient deficiencies are common even during remission. Understanding the underlying mechanisms can help explain why.

The location of nutrient absorption matters. Crohn's disease can affect any part of the GI tract from mouth to anus but most frequently involves the terminal ileum and colon, while ulcerative colitis is confined to the colon and rectum. Each nutrient is absorbed in a specific region of the gastrointestinal tract, so when IBD inflames or damages that exact segment, absorption is negatively impacted.

Inflammation itself can deplete nutrients given chronic inflammatory cytokines interfere with nutrient transport, and damaged tissue requires heightened nutrition to heal. Inflammation can also trap minerals within cells, creating deficiency even when dietary intake is adequate.

Nutrient losses and reduced food intake in a flare compound the issue. Diarrhea, GI bleeding, fistula, dietary restrictions, and certain IBD medications, including corticosteroids, methotrexate, sulfasalazine, and acid-suppressing agents, further contribute to nutrient loss or poor absorption.

Common Nutrient Deficiencies in Crohn's & Colitis

Iron

Iron is absorbed primarily in the duodenum and is lost due to GI bleeding and inflammation. It is estimated that roughly 35% to 90% of adults living with IBD experience iron deficiency at some point. Symptoms of low iron include fatigue, pallor, hair loss, heavy menstrual periods, headache, and poor concentration.

Vitamin B12

Vitamin B12 is absorbed predominantly in the terminal ileum, a common site of Crohn's involvement. Symptoms of low B12 include numbness, tingling, poor memory, an inflamed or burning tongue, and fatigue.

Zinc

Zinc is absorbed primarily in the duodenum and proximal jejunum and is lost through chronic diarrhea, with higher rates in Crohn's disease than ulcerative colitis. Symptoms of low zinc include hair loss, delayed wound healing, altered taste or smell, and skin changes reflecting a weakened skin barrier.

Calcium

Calcium is absorbed in the duodenum and jejunum, dependent on adequate vitamin D status. Symptoms of low calcium include muscle cramps, paresthesia, and reduced bone density over time.

Vitamin D

Vitamin D is absorbed alongside dietary fat in the small intestine. Fat digestion can be impaired in IBD due to both mucosal injury and poor bile acid availability, thus limiting Vitamin D absorption. Vitamin D is further reduced by limited sun exposure during the winter months, and with sun avoidance in the summer due to photosensitivity that comes from use of certain medications (ie. sulfasalazine, etc.). Overt deficiency is typically found in 25-35% of IBD patients across various ages. Symptoms of low vitamin D include bone pain, muscle weakness, and increased susceptibility to seasonal illness or infections.

Folate

Folate is absorbed in the jejunum and is further depleted by methotrexate and sulfasalazine, with deficiency affecting approximately 22% of Crohn's patients compared to about 4% of ulcerative colitis patients. Symptoms of low folate include oral ulcers, macrocytic anemia, and fatigue.

The Importance of Nutritional Screening in IBD

Nutrient deficiencies frequently develop silently, often preceding symptoms by months to years. Nutritional Screening in IBD and routine laboratory monitoring allows for early identification and intervention, even during periods of clinical remission.

Be sure to ask your Naturopathic doctor and gastroenterologist which laboratory panels are appropriate based on your concerns and history.

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References

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