Mothers-to-be who increase their levels of B12 in early pregnancy are about eight times more likely to have babies who don’t cry excessively, says a Dutch study.
A team in the Netherlands measured B12 levels in the blood of 3,000 women at the time of their first prenatal appointment, at about three months. Once the babies were born, their parents recorded how often their babies cried and for how long. Mothers with low levels of B12 were significantly more likely to have babies who cried excessively, defined as three or more hours a day.
Researchers suggested that low levels of B12 may affect the brain’s production of myelin, a supportive tissue that surrounds and protects nerve cells, during fetal development. A lower level of myelin could cause irritability. It’s also possible that B12 could be related to sleep cycles, as low levels stop the release of the sleep hormone melatonin.
Vitamin B12, which aids the development of babies’ brains and nervous systems, is most commonly found in fish, dairy products, eggs, and meat. Vegetarians and vegans can increase their B12 levels by taking a prenatal supplement. Supplements also contain folic acid, another critical pregnancy vitamin that can prevent birth defects such as spina bifida.