What foods are high in folic acid (Vitamin B9) to meet the daily suggested intake of 400 micrograms (mcg)?

Foods High in Folic Acid to Meet 400 mcg Daily Recommendation

While guidelines emphasize that enriched cereal grain flours fortified with synthetic folic acid are the primary food source designed to help meet the 400 mcg daily requirement, it is difficult for most women to consume the recommended daily folic acid from food alone, even with access to fortified foods—making supplementation essential. 1

The Reality of Food-Based Folic Acid Intake

The evidence clearly shows that dietary sources alone are insufficient:

• Food fortification in the United States adds only approximately 128 mcg of folic acid per day from enriched cereal grains, which is far below the 400 mcg target 2
• The FDA mandated fortification of enriched cereal grain flours with 140 mcg synthetic folic acid per 100 grams of grain in 1998, but this level may not be sufficient to protect against all folic acid-preventable neural tube defects 1
• The USPSTF acknowledged in their 2017 systematic review that it is difficult for most women to consume the recommended daily folic acid from food alone despite access to fortified food 1

Key Distinction: Folate vs. Folic Acid

Understanding the difference is critical for meeting daily requirements:

• Natural food folates are only about half as bioavailable as synthetic folic acid found in supplements and fortified foods 1
• Synthetic folic acid in supplements is approximately twice as bioavailable as naturally occurring folates found in food, meaning it is more efficiently absorbed 3
• Folate occurs naturally in dark green leafy vegetables, liver, kidneys, and yeast, but the lower bioavailability makes it challenging to reach 400 mcg through these sources alone 4, 5

Fortified Foods as Primary Dietary Source

The most practical food-based approach focuses on fortified products:

• Enriched cereal grain products (breads, pasta, rice, cereals) are the main fortified foods in the US food supply 1
• Corn masa flour received voluntary folic acid fortification approval in 2016 to address disparities in Hispanic populations 1
• Even with consistent consumption of fortified grains, the average intake from food fortification is only 128 mcg/day—leaving a 272 mcg gap to reach the 400 mcg target 2

The Supplementation Imperative

Given the limitations of dietary sources, guidelines universally recommend supplementation:

• All women of childbearing age should take 400 mcg (0.4 mg) of folic acid daily in the form of a supplement, multivitamin, and/or through fortified foods, in addition to eating a healthy diet 1, 6
• The average dietary folate intake from natural food sources is approximately 230 mcg, which is half the recommended amount 7
• A multivitamin containing 400 mcg of folic acid, combined with dietary intake (approximately 230 mcg) and food fortification (approximately 128 mcg), provides adequate total intake without exceeding the 1000 mcg upper limit 7

Common Pitfall to Avoid

• Do not rely solely on natural folate-rich foods (spinach, broccoli, legumes, citrus fruits) to meet the 400 mcg requirement, as their bioavailability is only 50% that of synthetic folic acid, making it nearly impossible to achieve adequate intake through diet alone 1, 2
• Women following low-carbohydrate diets that restrict enriched grain products are at particular risk for inadequate folic acid intake and require supplementation 1