Vitamin D

Vitamin D During Pregnancy May Play a Role in Children’s Cognitive Development, ECHO Study Suggests

Posted on by Jodi Snare

Higher vitamin D levels during pregnancy may be linked to better scores on cognitive tests, according to a new study by the Environmental influences on Child Health Outcomes (ECHO) Cohort.

Researchers found that children whose mothers had higher vitamin D levels while pregnant tended to perform better on cognitive tests assessing skills like problem-solving and processing new information at ages 7 to 12. However, vitamin D levels were not linked to skills based on learned knowledge, such as vocabulary. The association appeared strongest among children of Black mothers, and vitamin D levels measured earlier in pregnancy seemed most important for children’s brain development. Black people often have lower vitamin D levels because their skin has more pigment, which makes it harder for the skin to produce vitamin D from sunlight.

“Our study provides important new evidence that early pregnancy may be a critical period when vitamin D has the greatest potential to support cognitive development, said Melissa M. Melough, PhD, RD of the University of Delaware, Newark. “This highlights a key opportunity for clinicians to enhance screening and support for vitamin D supplementation before and during pregnancy. “

Vitamin D deficiency is common during pregnancy and has been linked to early brain development, but few studies have examined whether these effects continue into later childhood or differ by racial group. The researchers emphasize that while these findings add to growing evidence on the role of vitamin D in pregnancy, further studies are needed to determine the optimal dose and timing of supplementation to support cognitive development.

This collaborative research was published in The American Journal of Clinical Nutrition.

Prenatal Vitamin D Levels Associated with Children’s Brain Development, ECHO Study Suggests

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Prenatal Vitamin D Levels Associated with Children’s Brain Development, ECHO Study Suggests

Authors: Melissa Melough, et al.

 

Who sponsored this study?

The Environmental influences on Child Health Outcomes (ECHO) Program, Office of the Director, National Institutes of Health supported this research.

 

Why was this study needed?

Vitamin D deficiency is one of the most common nutrient deficiencies in the world. In the U.S., it affects 80% of Black pregnant women and nearly half of pregnant women with incomes below the federal poverty level. Low vitamin D during pregnancy may harm childhood brain development, leading to lower academic achievement in adolescence. This study aimed to clarify how vitamin D levels during pregnancy may influence children’s brain development, particularly in varied groups and into later childhood. While prior research suggests prenatal vitamin D plays an important role in early brain development, few studies have examined whether these effects persist beyond early childhood or vary across groups that may be at higher risk for vitamin deficiencies. For example, Black people often have lower vitamin D levels because their skin has more pigment, which makes it harder for the skin to produce vitamin D from sunlight. Researchers sought to build on previous evidence by studying a varied cohort of mothers and their children, followed until ages 7 to 12.

 

What were the study results?

Researchers found that children whose mothers had higher vitamin D levels while pregnant tended to perform better on cognitive tests assessing skills like problem-solving and processing new information at ages 7 to 12. However, vitamin D levels were not linked to skills based on learned knowledge, such as vocabulary. The link between vitamin D and thinking skills was stronger in children of Black mothers compared to other racial groups. Results also suggested that vitamin D levels early in pregnancy were most important for children’s brain development. The largest differences in children’s cognitive skills—between those with the highest and lowest scores—were linked to their mothers’ vitamin D levels early in pregnancy, suggesting this may be a critical time for brain development.

 

What was the study's impact?

The study provides evidence that early pregnancy may be a critical period when vitamin D has the greatest potential to support brain development. Interventions prior to or earlier in pregnancy, and those focused on Black women and others at high risk of deficiency, may have the greatest impact.

 

Who was involved?

The study included 912 biological mother-child pairs from five ECHO Cohort research sites. Approximately 38% of participants were vitamin D-deficient.

 

What happened during the study?

Researchers measured vitamin D levels in pregnant women’s blood during pregnancy or in their babies’ cord blood at birth. They tested the children’s fluid and crystallized cognition when they were 7 to 12 years old using a standard set of cognitive tests. They analyzed how vitamin D levels during pregnancy were linked to children’s cognitive scores, while considering other factors that could affect the results. They also looked at whether certain times during pregnancy mattered more by comparing vitamin D levels across pregnancy in mothers of children with higher versus lower cognitive scores. This helped them identify when vitamin D might have the greatest impact on brain development.

Footnote: Results reported here are for a single study. Other or future studies may provide new information or different results. You should not make changes to your health without first consulting your healthcare professional.

What happens next?

Future research, including randomized trials, could help researchers identify the optimal dose and timing of vitamin D supplementation for children’s cognitive development.

 

Where can I learn more?

Access the full journal article, titled “Gestational vitamin D concentration and child cognitive development: a longitudinal cohort study in the Environmental influences on Child Health Outcomes Program,” in The American Journal of Clinical Nutrition.

The content is the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.

Published August 2025

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Prenatal Vitamin D Levels Associated with Children’s Brain Development, ECHO Study Suggests

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How Much Vitamin D do Children with Asthma and Increased Body Weight Need to Correct Low Vitamin D Levels?

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How much vitamin D do children with asthma and increased body weight need to correct low vitamin D levels?

Study title: Pharmacokinetics of Oral Vitamin D in Children with Obesity and Asthma

Author(s): Jason E. Lang, Rodrigo Gonzalez Ramirez, Stephen Balevic, Brian O’Sullivan, Scott Bickel, Christoph P. Hornik, J. Marc Majure, Saranya Venkatachalam, Jessica Snowden, Laura James

 

Why was this study conducted?

Among children with asthma, children who also have increased body weight for their height (body mass index (BMI) of ≥85 percentile) tend to have more severe asthma symptoms than their healthy weight peers. Children with asthma and increased body weight also tend to have lower vitamin D levels than other children. Helping children with asthma and increased body weight reach higher vitamin D levels may help their asthma symptoms by lowering inflammation in the lungs. However, there is not enough information on how much vitamin D children with asthma and increased body weight should take to safely raise their vitamin D levels.

 

What was done?

ECHO ISPCTN research teams in 15 states enrolled children ages 6‑18 years with asthma and increased body weight in a clinical trial. The children took vitamin D capsules for 16 weeks and gave blood samples every month so researchers could check their vitamin D levels. The goal of the study was to find a vitamin D dose that helped children raise their vitamin D levels in their blood to 40 ng/mL, a level that might lower inflammation.

There were two parts of the study. In the first part, children were split into four groups that each took one of four different doses of vitamin D to find a dose that raised children’s vitamin D levels over 16 weeks without causing side effects. All four dosing options were higher than what is usually recommended to raise vitamin D levels. Then, researchers compared the vitamin D dose from part 1 that raised vitamin D levels quickly and safely to the usually recommended daily vitamin D dose to confirm that the higher dose could safely help children reach vitamin D levels that may decrease inflammation. This study was approved by the Institutional Review Board and all participants consented to participate in the study.

 

What was found?

The first part of the study found that taking a 50,000 international units (IU) vitamin D dose on the first day of treatment and then an 8,000 IU vitamin D dose every day for 16 weeks was most effective at raising vitamin D levels safely. In the second part of the study, researchers confirmed that using this approach raised vitamin D levels in most children to the recommended level while avoiding undesired higher levels. In contrast, no children who followed the current standard-of-care dosing of 600 IU each day achieved the target vitamin D level sufficient to potentially reduce inflammation.

 

What do the results mean?

Most children with asthma and increased body weight who take vitamin D the vitamin D dose used in this study (50,000 IU vitamin D on day one, then 8,000 IU each day) can safely raise their vitamin D level in a short period of time. The newly determined dose is much greater than the typically recommended dose. This study shows how important it is that children and adolescents with increased body weight get enough vitamin D in their diet or in vitamin supplements every day since the higher the body weight, the faster vitamin D was processed and removed from the body. The results of this study may help children with asthma or other illnesses if having enough Vitamin D lowers inflammation.

 

Who sponsored the study?

This research was supported by the Environmental influences on Child Health Outcomes (ECHO) program, Office of The Director, National Institutes of Health.

 

Appreciation

All of the families in ECHO ISPCTN trials help study teams across the country learn more every day about how to bring rural and underserved families into research studies. This is critical to ensure that families that are not near large academic centers still get the benefits of research and that the “answers” research studies find are meaningful for children and families across all parts of the country, not just those who live in large cities.

 

You may learn more about this publication here: https://link.springer.com/article/10.1007/s40262-023-01285-9

 

The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.

 

Published: August 30, 2023

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How much vitamin D do children with asthma and increased body weight need to correct low vitamin D levels?

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