Birth Defects From B-12 Deficiency
If you're vegan or vegetarian and you want to procreate, you should know about a new study just published in the journal, Pediatrics. The study found that women who have a vitamin B-12 deficiency stand a greatly increased risk of giving birth to children with severe "neural tube" birth defects. Since B-12 comes primarily from meat, dairy, and fish sources, those who eschew animal foods are particularly at risk.
Neural tube defects involve the brain and spinal cord, causing conditions such as spina bifida, which deforms the spine and backbone and results in paralysis; and anencephaly, a fatal condition that causes underdeveloped brain function. According to the research, those women with the lowest levels of B-12 run up to five times the chance of giving birth to children with neural tube birth defects, compared to women with sufficient stores of the vitamin. Folic acid deficiency also has been linked with natal birth defects, but even when folic acid levels were controlled for, subjects with low B-12 showed elevated risk levels. In other words, both folic acid and B12 levels must be sufficient in order to diminish risk.
While obstetricians these days usually make sure that their pregnant patients take vitamin supplements, according to researcher Dr. James Mills of the National Institutes of Health, "An absolutely critical point is that women have to consider this [need to supplement with vitamin B12] before they become pregnant because once they realize they are pregnant it's likely to be too late." In other words, "cramming" won't work, and since neural tube birth defects tend to occur in the first month of pregnancy, neither will starting the B-12 regimen after conception. Women need to have adequate B-12 both before and after conceiving. Click here for more information on Supplements from Preconception on Up.
In fact, whether or not having babies is on your to-do list, it's essential to ensure that you have an adequate B12 intake. As Dr. Duane Alexander, director of the Eunice Kennedy Shriver National Institute of Child Health and Human Development, said, "Vitamin B12 is essential for the functioning of the nervous system and for the production of red blood cells. The results of this study suggest that women with low levels of B12 not only may risk health problems of their own, but also may increase the chance that their children may be born with a serious birth defect."
Those "health problems of your own" might include pernicious anemia, fatigue, depression, memory loss, psychosis, spinal degeneration, nerve degeneration and irreversible neurological impairment. A study last year at Oxford University found that low levels of B12 in elderly people seemed linked to brain atrophy and shrinkage, which in turn can lead to Alzheimer's. In that study, the subjects who had the lowest B12 levels lost brain volume six times faster than those who had the highest levels of the vitamin. Even more startling, none of the subjects actually showed a B12 deficiency; rather, those with "low levels" were simply in the low-normal range.
Deficiency of vitamin B12 appears common in elderly people, as well as among those with intestinal disorders that lead to poor vitamin absorption (B12 and many other vitamins need a proper cocktail of stomach acid to be absorbed) and, as mentioned before, among vegetarians. According to the Vegetarian Society, while some plant sources do contain significant amounts of B12 -- including spirulina, fermented soy, and seaweed -- the type of B12 in these foods isn't useable by the body. What they contain are B12 analogues (chemical look-alikes) that your body cannot use, and so it's almost impossible for vegans to get enough B12 through diet alone. Vegetarians who eat eggs aren't much better off, because the B12 in eggs also isn't bio-available. Dairy, on the other hand, contains useable B12, but as I've written before, milk products come with a host of other issues, as do many prepared foods fortified with synthetic B12. Nutritional yeast, on the other hand, is a good source of useable vegetarian B12.