Crohn’s disease inflames the lining of the digestive tract and can have severe symptoms. Researchers in one study compared blood levels of vitamin B12 and folate in 45 people with Crohn’s disease to levels in 53 healthy people. Those with Crohn’s disease were three times more likely to be deficient in vitamin B12 and seven times more likely to be deficient in folate. Vitamin B12 levels were 18 percent higher and folate levels were 20 percent higher in healthy people compared to those with Crohn’s disease. Doctors believe that vitamin B12 and folate—the active form of folic acid—help control inflammation by lowering homocysteine levels.