to increase their folate consumption to the Recommended Dietary Allowance (RDA) level (400 µg/day of DFEs) could readily do so by consuming fortified cereal grains. They could also increase intake of foods that are naturally high in folate, such as orange juice and cooked dried peas and beans, eat more foods that are good sources of folate, and eat fewer foods that contain none (such as soft drinks and most candy). For women capable of becoming pregnant, taking 400 µg/day of folate from fortified food, supplements, or a combination of the two is recommended to reduce the risk of neural tube defects.
One combination of fortified foods that would provide 400 µg of added folate is
2 servings of moderately fortified ready-to-eat cereal (200 µg of folate),
7 slices of bread or alternate (140 µg of folate), and
1 cup of rice or pasta (60 µg of added folate).
According to the serving sizes specified in the Food Guide Pyramid (USDA, 1992), this would be 11 servings of cereal grains— much more than that consumed by many women. It is the upper limit of the recommendation to consume 6 to 11 servings made in the Food Guide Pyramid.
It is recommended that adults over age 50 obtain their vitamin B12 mainly as synthetic B12 from fortified foods or supplements because absorption of food-bound B12 may be limited (see Chapter 9). The main food sources of synthetic vitamin B12 are fortified ready-to-eat cereals and soy-based meat substitutes (see Table 9-10). If these foods provide 25 percent of the current daily value designated on the product label, they provide 1.5 µg of synthetic B12 (more than half the RDA for B12 for older adults of 2.4 µg/day).
Each reference value should be used for its intended purpose. The Recommended Dietary Allowance (RDA) and the Adequate Intake (AI) are intended for use primarily as goals for intake by individuals. Special attention to the form of folate and vitamin B12 is often warranted.