Vegetarian Diets, Pregnant Women and Vitamin B12

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A study done in Germany demonstrates that pregnant vegetarian women may not have an adequate supply of vitamin B12. This study was performed at the German Institute of Human Nutritrion in Postdam-Rehbrücke located in Nuthetal, Germany.

Vitamin B12 is only found naturally in foods derived from animal sources. However, many women are opting to restrict themselves to diets of predominantly plant origin in the belief that this will increase their lifespan and reduce the likelihood of death from heart disease.

Many pregnant vegetarians are choosing to include eggs and milk in their diets to supply them with vitamin B12, which is necessary for proper nerve formation in the fetus. Hence, their diet is referred to as the “lacto-ovo-vegetarian diet.” This particular study in Germany was done in reaction to other studies that showed that infants born to mothers on strictly vegetarian (vegan) diets were deficient in vitamin B12.

A woman who is B12 deficient is at a greater risk during pregnancy for pre-eclampsia and other pregnancy-related complications. Furthermore, the fetus is at greater risk for neural tube defects. A breast-fed infant of such a woman has a greater likelihood for developmental abnormalities and growth failure.

The purpose of the study in Germany was just to compare the blood plasma vitamin B12 levels of women who ate a traditional western diet (meat eaters) with women on a vegan diet and ovo-lacto-vegetarian diet.

Over one hundred pregnant women were recruited for the study and divided into three groups: The ovo-lacto-vegetarian group, the low-meat eater group, and the control group. The ovo-lacto-vegetarians were women who never ate meat at all in the three years prior to the study. The women in the control group were not on any diet (regular meat eaters). Blood samples were taken from all the women throughout their pregnancies.

As far as Body Mass Index (BMI) is concerned, the vegetarians and low-meat eaters had lower pre-pregnancy BMIs than the control group (meat eaters).

With regard to B12 concentrations, the vegetarian and low-meat eaters had much lower levels of vitamin B12.  There was not much difference between the vegetarian and the low-meat eaters groups.

In summary, the study demonstrates that women on vegetarian diets are at greater risk for a B12 deficiency, thus placing their infants at a greater risk for neural tube defects.

If you are pregnant and do not eat much meat, it is highly recommended that you supplement your diet with vitamin B12.