Vitamin [B.sub.12] in pregnancy

Vegetarian Journal, May-June, 2005 by Reed Mangels

Adequate vitamin [B.sub.12] intake is important in pregnancy. While vegan women often use fortified foods as their main source of vitamin B12, women who follow a lacto-ovo vegetarian diet may choose dairy products as their primary source of vitamin [B.sub.12]. Dairy products can provide an adequate amount of this vitamin, but simply drinking a cup or two of cow's milk daily may not be enough to meet [B.sub.12] needs in pregnancy.

Researchers in Germany and The Netherlands studied more than 100 women--approximately one-fourth followed a lacto-ovo vegetarian diet, 40 percent ate less than 10 ounces of meat per week, and 40 percent ate a standard diet (> 10 ounces of meat per week). Vitamin [B.sub.12] intake was lowest in the vegetarians, followed by the low meat-eaters, while the women eating a standard diet had the highest. Approximately 60 percent of the vegetarian women met recommendations for vitamin [B.sub.12] using a combination of dietary sources (mainly milk and dairy products) and supplements, but 40 percent of women had vitamin [B.sub.12] intakes below recommendations. Dietary intake was reflected in blood vitamin [B.sub.12] levels; close to 40 percent of the vegetarian women, 9 percent of the low meat-eaters, and 3 percent of the meat-eaters had low blood vitamin [B.sub.12] levels at some point in their pregnancy.

Low blood vitamin [B.sub.12] levels were only found in women who had a vitamin [B.sub.12] intake of less than 4 micrograms per day. The recommended daily allowance (RDA) for pregnancy is 2.6 micrograms. Thus, even women whose dietary vitamin [B.sub.12] intake met recommendations could still have low blood vitamin [B.sub.12] levels. These results suggest that the RDA for vitamin [B.sub.12] in pregnancy is too low. Pregnant women should be aware of good sources of vitamin [B.sub.12]. Good sources include foods fortified with vitamin [B.sub.12] like fortified soymilk (0.8-3.2 micrograms per cup), fortified breakfast cereals (0.6-6 micrograms per ounce), and Vegetarian Support Formula nutritional yeast (1.5 micrograms in 1 Tablespoon mini-flakes).

Koebnick C, Hoffmann I, Dagnelie PC, et al. 2004. Long-term ovo-lacto vegetarian diet impairs vitamin [B.sub.12] status in pregnant women. J Nutr 134: 3319-26.