Which birth defect has declined since the fortification of greens with folic acid (Vitamin B9) began?

From the Guidelines

Neural tube defects have significantly declined since the fortification of foods with folic acid (Vitamin B9) began. The mandatory fortification of grain products with folic acid, implemented in many countries including the United States in the late 1990s, has led to a 20-30% reduction in neural tube defects such as spina bifida and anencephaly, as reported by the USPSTF 1. These serious birth defects affect the brain, spine, or spinal cord and develop very early in pregnancy, often before a woman knows she is pregnant. Folic acid works by supporting proper cell division and DNA synthesis during the critical first weeks of fetal development when the neural tube is forming. Some key points to consider:

• The recommended daily intake of folic acid for women of childbearing age is 400 micrograms, with higher doses (600-800 micrograms) recommended during pregnancy, as suggested by the USPSTF 1.
• Women planning pregnancy are advised to begin folic acid supplementation at least one month before conception and continue through the first trimester to maximize the protective effect against these birth defects, as recommended by the USPSTF 1.
• The use of certain antiseizure medicines and a personal or family history of neural tube defects are well-established risk factors, and other reported risk factors include mutations in folate-related enzymes, maternal diabetes, and obesity, as reported by the USPSTF 1.
• The USPSTF concludes that, for women who are planning or capable of pregnancy, there is high certainty that the net benefit of folic acid supplementation is substantial, as stated in their recommendation statement 1.

From the Research

Birth Defects Decline

The decline in birth defects due to fortification of greens with folic acid is a significant public health achievement. Some of the key birth defects that have declined include:

• Neural tube defects (NTDs) such as spina bifida and anencephaly 2, 3, 4, 5, 6

Specific Declines

Specific declines in birth defects have been reported in various studies, including:

• Spina bifida: 31% decline 2, 21% decline 6, 40% decline in Arkansas 4
• Anencephaly: 16% decline 2, 20% decline 6

Prevention Strategies

Prevention strategies for NTDs include:

• Folic acid supplementation: recommended daily intake of 400-800 μg for women planning or capable of pregnancy 3, 5
• Mandatory folic acid fortification of staple foods: safe, economical, and effective intervention for primary prevention of NTDs 3