Building Brains: B12 During Pregnancy & Childhood IQ

In this episode of Daily Value, we look at the role of maternal Vitamin B12 intake during pregnancy and its impact on a child’s IQ. Drawing on findings from the ELSPAC study (PMID: 39674678), we discuss how Vitamin B12 supports critical neurodevelopmental processes and how deficiency may impact verbal IQ.

Discussion Points:

• The role of Vitamin B12 in one-carbon metabolism, axon myelination, and DNA methylation, and their importance for fetal brain development.
• Findings from the ELSPAC study, where higher maternal Vitamin B12 intake was associated with improved language skills at 18 months and higher verbal IQ at 8 years.
• The importance of addressing elevated homocysteine levels during pregnancy to mitigate neurodevelopmental risks.

https://pubmed.ncbi.nlm.nih.gov/39674678/#:~:text=Conclusions%3A We identified consistent associations,particularly in speech and language.

Transcript

Speaker 0: 0:00

Could a nutrient deficiency that affects you impact the IQ of your child? Hello everyone and welcome back to Daily Value. I'm William Wallace and today we're looking into the relationship between maternal vitamin B12 intake during pregnancy and the neurocognitive development of offspring. This discussion is grounded in recent findings from the European Longitudinal Study of Pregnancy and Childhood, also called ELSPAC, a study that brings fresh insights into a topic that, to this point, has had equivocal and contradictory findings the critical role of maternal B12 levels and how that possibly affects a child's neurocognitive development. Brain development is influenced by the frequency and timing of nutrient intake, so it stands to reason that nutrients critical for field development and there are many would have different impacts depending on the timing and severity of the deficiency on that developmental timeline. While the importance of folic acid, iodine and iron during pregnancy is well documented, the impact of vitamin B12 on neurodevelopment remains less consistently characterized to this point in time. However, its biochemical roles suggest it is indispensable for optimal cognitive outcomes, especially during development. For instance, axon myelination. Vitamin B12 facilitates the synthesis of myelin, that's the fatty layer surrounding axons, to insulate them and ensure efficient impulse conduction between neurons in the central nervous system. Disruptions in this process can impair sensory and cognitive function. Vitamin B12 supports DNA synthesis and neurogenesis. It is required for nucleotide synthesis. Dna is made up of nucleotides and supports cellular proliferation in developing brain regions, particularly in auditory and visual centers.

Speaker 0: 1:57

Vitamin B12, specifically the methylcobalamin form, plays a role in homocysteine regulation. Methylcobalamin is a coenzyme for the enzyme methionine synthase, which is one of the four enzymes involved in the breakdown of homocysteine. Elevated homocysteine levels during pregnancy have been tied to adverse pregnancy outcomes that include lower scores in expressed language and motor skills. In the early part of a child's life, vitamin B12 plays an important role in reducing neurotoxic homocysteine levels and promotes the synthesis of S-adenosylmethionine, otherwise known as SAMe. That's a universal methyl donor necessary for epigenetic regulation.

Speaker 0: 2:40

Now, the connection between vitamin B12 status of a mother and language skills in her offspring is something that has come up repeatedly in observational studies conducted around the world. Language skills, we know, influence a broad set of cognitive domains and are a strong predictor of not only later academic success, but success integrating oneself into social environments, which, no surprise, is a predictor of general later life success. Studies published by Cruz Rodriguez in 2023 and 2024 as part of the Eclipse study found that vitamin B12 levels of the mother in the first trimester were associated with better motor function after birth and higher work and memory scores once the child reached the age of four. Another study in 2021 found that children of mothers with low prenatal vitamin B12 levels had lower speech, language and math abilities in early childhood. However, not all studies on this topic find the same thing, which brings us to a study that was published last month in one of the Oxford academic journals, the Journal of Public Health, the ELSPAC study, as it was called led by Rezova et al I hope I pronounced that name right. They looked at the association between maternal B12 intake and child development milestones across a cohort of 5,000 mother-child pairs. Specifically, they wanted to know if maternal B12 status affected language outcomes in children. Key outcomes were assessed using parent-reported measures of speech and language at age 18 months and 3, 5, and 7 years, as well as an IQ evaluation at 8 years. The findings were as follows A higher maternal vitamin B12 intake was positively correlated with improved language scores at 18 months. Children of mothers in the highest quartile of vitamin B12 intake scored significantly better in both vocabulary and comprehension tasks. Elevated maternal homocysteine levels indicative of suboptimal vitamin B12 status were associated with poorer expressive language performance in early childhood, not when looking at verbal IQ. Now, while there was no association with vitamin B12 status and total IQ, verbal IQ was notably higher in children at eight years old whose mothers had greater vitamin B12 intake during pregnancy, even after adjusting for confounders like maternal education, smoking status and dietary supplementation. These particular results are not only supported by some of the past research I mentioned just a minute ago, but also by other studies, including a randomized control trial published in 2021 that showed preconception supplementation of vitamin B12 did result in improved language skills at two years of age, as well as higher expressive language scores at two and a half years of age. Given these findings, ensuring adequate maternal vitamin B12 intake should be a priority during prenatal care, particularly as plant-based diets seem to become more prevalent.

Speaker 0: 5:56

Vitamin B12 is predominantly sourced from animal-derived foods. It's primarily found in animal foods because it's produced by microorganisms like bacteria, not by plants or animals themselves. Animals obtain vitamin B12 either by consuming these bacteria directly or by hosting them in their digestive systems. For instance, ruminants like cows and sheep have gut bacteria that produce vitamin B12, which is then absorbed in their intestines. This makes animal-based foods like meat, fish, eggs and dairy rich and bioavailable sources of vitamin B12. On the other hand, plants don't naturally contain B12, as they lack the bacteria needed to produce it, so any trace amounts in plants usually comes from soil contamination of some kind. This is why people following vegan or vegetarian diets often need to rely on fortified foods or supplements to meet their vitamin B12 needs.

Speaker 0: 6:52

The FDA recommends a minimum of 2.4 micrograms a day for adult women over 19 years old. That number increases to 2.6 micrograms a day for pregnant women and further to 2.8 micrograms a day for breastfeeding women. The European Food Safety Authority recommends 4.5 micrograms a day during pregnancy. Now emerging evidence suggests that higher intakes may be beneficial for optimal neurodevelopmental outcomes, and typically you'll see much higher doses in prenatal supplements. In fact, prenatal vitamins containing methylcobalamin and or hydroxycobalamin are usually a wise choice during pregnancy. Adenosylcobalamin is another active form of vitamin B12 that is good to have on hand, and one I don't feel gets appreciated enough. The ELSPAC study adds to a growing body of evidence highlighting the role of maternal nutrition in shaping a child's cognitive trajectory. As we refine our understanding of vitamin B12's mechanistic roles, it's important to translate these findings into dietary guidelines and public health strategies that prioritize maternal and fetal health. Thank you for joining me today on this episode of Daily Value. If you found this discussion valuable, consider sharing it with your network. As always, stay informed and stay healthy.