Why People With IBD Are Often Deficient in Folic Acid

Folate is a water-soluble, B-complex vitamin that is important to the body for several functions including creating new cells and making red blood cells. Specifically, folic acid is also known as vitamin B9.

Close-up of asparagus in frying pan
Zuzana Gajdosikova / EyeEm / Getty

It is called folate when it is found in foods, such as legumes, fruits, and green leafy vegetables. Folic acid is the synthetic version of folate that is found in many fortified foods (such as breads and cereals) and as a supplement.

People with inflammatory bowel disease (IBD) are at risk for folate deficiency, especially those who are taking methotrexate or sulfasalazine.

Why Folic Acid Is Important

The body can not make folate or folic acid, so it must be obtained from food and supplements. Folate is a B vitamin that is important before and during pregnancy because it is used in cell creation and division. An adequate intake of folate is needed to prevent neural tube defects such as spina bifida in a baby.

Folate is also necessary for the body to maintain proper levels of the amino acid homocysteine, which is needed by the body for protein synthesis. Without enough folate, homocysteine will build up in the body. High levels of homocysteine are associated with cardiovascular disease.

Folate may also help prevent cancer by preventing certain changes in the body's DNA. Because folate is needed to create red blood cells, getting enough folate is also important to prevent anemia, specifically megaloblastic anemia.

Why IBD Patients Are at Risk for Folate Deficiency

People who have Crohn's disease in their small intestine are at risk for malabsorption of many vitamins and minerals—folate included. Folate is absorbed by the middle and the last part of the small intestine, the jejunum, and the ileum.

Sulfasalazine and methotrexate are two medications used to treat IBD that may interfere with the metabolism of folate.

Other reasons for poor folate absorption include alcohol abuse, liver disease, and the use of anticonvulsant medications, metformin, triamterene, or barbiturates.

Is Every Person With IBD at Risk for Folate Deficiency?

One study published in 2009 showed that newly diagnosed pediatric patients have higher folate levels than kids who do not have IBD. The authors were surprised, given that the reverse has been found true among adult IBD patients. Folate levels in children with IBD may need to be monitored to determine if supplements are truly needed.

IBD patients are at risk for elevated levels of homocysteine. Homocysteine is an amino acid, and levels that are too high are associated with blood clots and heart attacks. In people with IBD, a folate deficiency may or may not be to blame for elevated homocysteine—the evidence is conflicting. At least one study published in 2001 has shown that increased homocysteine in people with IBD may be a result of low levels of the vitamin B12, rather than low levels of folate.

Preventing Folate Deficiency With Folic Acid Supplements and Dietary Choices

To prevent a folate deficiency, it may be recommended that people with IBD take a supplement of folic acid. Those taking sulfasalazine and methotrexate, in particular, may need extra folic acid. A folic acid supplement of 1000 micrograms (1 milligram) a day is often recommended for those most at risk of folate deficiency.

Check with your healthcare provider to determine how much folic acid you need daily and whether you need to take any supplements.

Some foods that have folate or folic acid are:

  • Asparagus
  • Beef liver
  • Broccoli
  • Cowpeas
  • Fortified cereals, rice, egg noodles, and bread
  • Great Northern beans
  • Green peas
  • Spinach
8 Sources
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  1. Office of Dietary Supplements. Dietary Supplement Fact Sheet: Folate.

  2. Pan Y, Liu Y, Guo H, et al. Associations between Folate and Vitamin B12 Levels and Inflammatory Bowel Disease: A Meta-AnalysisNutrients. 2017;9(4):382. doi:10.3390/nu9040382

  3. Centers for Disease Control and Prevention. Folic Acid Helps Prevent Some Birth Defects.

  4. Ganguly P, Alam SF. Role of homocysteine in the development of cardiovascular diseaseNutr J. 2015;14:6. doi:10.1186/1475-2891-14-6

  5. Hwang C, Ross V, Mahadevan U. Micronutrient deficiencies in inflammatory bowel disease: from A to zinc. Inflamm Bowel Dis. 2012;18(10):1961-81. doi:10.1002/ibd.22906

  6. Burke G. Haematology. Essential Human Disease for Dentists. 2006:139-161. doi:10.1016/b978-0-443-10098-7.50012-9.

  7. Heyman MB, Garnett EA, Shaikh N, et al. Folate concentrations in pediatric patients with newly diagnosed inflammatory bowel diseaseAm J Clin Nutr. 2009;89(2):545–550. doi:10.3945/ajcn.2008.26576

  8. Romagnuolo J, Fedorak RN, Dias VC, Bamforth F, Teltscher M. Hyperhomocysteinemia and inflammatory bowel disease: prevalence and predictors in a cross-sectional study. Am J Gastroenterol. 2001;96(7):2143-9. doi:10.1111/j.1572-0241.2001.03950.x

By Amber J. Tresca
Amber J. Tresca is a freelance writer and speaker who covers digestive conditions, including IBD. She was diagnosed with ulcerative colitis at age 16.