Folic Acid Deficiency

Key points

Newcomer children with hemoglobinopathies are at risk of folic acid deficiency.
Folic acid deficiency is more common in pregnant women from low-resource countries.
Folic acid deficiency can lead to birth defects, megaloblastic anemia and depression.
Asymptomatic children with folic acid deficiency can be treated using dietary sources. Children with a chronic deficiency or at high risk of developing one should receive a folic acid supplement.

Prevalence

Although the prevalence of folic acid deficiency among pregnant newcomers to Canada is not known, World Health Organization data have shown low serum folic acid levels among pregnant women in countries such as Sri Lanka (57%), India (41.6%), Myanmar (13%) and Thailand (15%).¹

Etiology

Folic acid is required for DNA production and cell growth. While deficiency is mainly due to dietary insufficiency, gastrointestinal diseases such as celiac disease or Crohn’s disease can reduce folic absorption. Certain medications, such as some anticonvulsants and sulfonamides, can also interact with folic acid levels.

Newcomer children with hemoglobinopathies are at risk for folic acid deficiency.

Consequences

Folic acid deficiency can result in megaloblastic anemia, diarrhea, peripheral neuropathy, mental confusion and depression. Deficiency in folic acid during pregnancy can lead to birth defects, most notably neural tube defects, and other congenital anomalies. Folic acid supplementation combined with a multivitamin supplement in pregnancy has been associated with a decrease in specific birth defects.²

Diagnosis

Folic acid deficiency (as well as vitamin B12 deficiency) may result in megloblastic anemia. Low levels of serum folate can help with the diagnosis where the usual range is 2.5 to 20 ng/mL. Additional tests include serum homocysteine, serum methylmalonic acid and red blood cell folate level.

Prevention

Asymptomatic children with folic acid deficiency can be managed with a diet rich in folate, or supplemented by a multivitamin with folic acid. Children with clinical folic acid deficiency and those at high risk should be treated with supplemental folic acid.

The recommended daily intake of folate for all age groups, including infants, children and adolescents, is available from Health Canada.

**Table 1: Dietary sources of folate**
Food	Milligrams
Ready-to-eat cereal, fortified, 1 serving	0.4
Potato, baked, flesh and skin, 1 medium	0.70
Banana, raw, 1	0.68
Garbanzo beans, 4 oz	0.57
Chicken breast, ½ breast	0.52
Oatmeal, instant, fortified, 1 packet	0.42
Pork loin, lean, 3 oz	0.42
Roast beef, lean, 3 oz	0.32
Trout, rainbow, 3 oz	0.29
Sunflower seeds, 1 oz	0.23
Spinach, 8 oz	0.14
Tomato juice, 6 oz	0.20
Avocado, 8 oz	0.20
Salmon, sockeye, 3 oz	0.19
Tuna, 3 oz	0.18
Wheat bran, 4 oz	0.18
Peanut butter, 2 tbs	0.15
Walnuts, 1 oz	0.15
Lima beans, 8 oz	0.10
Soybeans, green, 8 oz	0.05
Source: B.C. Ministry of Health, Folate deficiency, investigation and management, 2012. Adapted with permission.

Selected resources

Centers for Disease Control and Prevention. Immigrant and refugee health.
Health Canada, 2007. Eating well with Canada’s food guide is available in multiple languages.
U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Center for Emerging and Zoonotic Infectious Diseases. Guidelines for evaluation of the nutritional status and growth in refugee children during the domestic medical screening process. Bethesda, MD: CDC, April 2012.

References

Bhutta ZA, Hasan B. Periconceptional supplementation with folate and/or multivitamins for preventing neural tube defects: RHL commentary. Geneva, Switzerland: WHO, 2002.
Wilson RD, Johnson JA, Wyatt P, et al. Pre-conceptional vitamin/folic acid supplementation 2007: The use of folic acid in combination with a multivitamin supplement for the prevention of neural tube defects and other congenital anomalies. J Obstet Gynaecol Can 2007;29(12)1003-1026, especially guideline 201.

Reviewer(s)

Anna Banerji, MD
Andrea Hunter, MD

Last updated: May, 2013