10 Vitamins You May Need if You Have Crohn's

Folic acid is another B vitamin and it's essential for forming new cells.

Folic acid is especially critical in pregnant women to prevent birth defects. But the drugs sulfasalazine (Azulfidine) and methotrexate can cause deficiencies.

The CCFA recommends that people taking sulfasalazine, in particular, fortify themselves with 1 milligram of folate a day as a supplement.

Diarrhea is a common symptom of Crohn's disease and people with excessive, watery diarrhea can find their bodies deprived of magnesium and potassium, says Nirmal Kaur, MD, medical director of the Inflammatory Bowel Disease Center at Henry Ford Health System in Detroit.

The mineral is critical for a variety of body processes, including keeping the heart, muscles, and kidneys in good working order. Symptoms of a deficiency can include anxiety, difficulty sleeping, nausea and vomiting and

restless legs syndrome.

Prolonged diarrhea can also deplete zinc reserves. And a zinc deficiency can lead to more diarrhea, creating a "vicious cycle," says Dr. DeCross.

This type of deficiency is rare, though children may be at greater risk. A 2011 study in the journal Clinical Pediatrics found that children recently diagnosed with Crohn's disease had lower zinc levels than their healthy counterparts.

Zinc deficiency can result in slowed growth, loss of appetite, and can also compromise the immune system.

People whose lower intestines have been damaged or removed due to Crohn's disease may have difficulty absorbing vitamin A. More commonly, though, deficiencies may occur if Crohn's has resulted in any obstruction of the intestine. The ileum usually has a small population of bacteria. When the intestine is blocked, however, fluid can stagnate, causing a "festival" of bacteria, says Dr. DeCross. "The bacteria will compete for and consume vitamin A," he says.

Another casualty of damage to the ileum is vitamin E, known for its anti-oxidant properties. Symptoms can include tingling and numbness in the fingers and toes (known as peripheral neuropathy) and muscle weakness.

Vitamin E can be found in nuts, seeds, vegetable oils, green leafy vegetables, and fortified cereals. But people with Crohn's may need water-soluble forms of vitamin E, such as tocopheryl polyethylene glycol-1000 succinate.