A new analysis suggests that taking high doses of vitamin D during pregnancy may be associated with improved memory in children. Researchers from the University of Copenhagen examined data from a clinical trial that compared two groups of expectant mothers: one group received a standard 10-microgram daily dose of vitamin D, while the other took a higher 70-microgram dose.
Study Findings
The study included approximately 500 children, whose memory performance was assessed at the age of 10. Results indicated that children whose mothers had taken the higher-dose supplements scored slightly better on memory tests compared to those whose mothers received the standard dose.
Professor Andrew Shennan, professor of obstetrics at King's College London, commented: "Given how cheap and safe vitamin D is at these doses, it could have a significant public health benefit in the future if the findings are real." He noted that the results align with previous evidence from animal studies.
Caveats and Expert Opinions
However, Professor Shennan cautioned that the findings should be interpreted carefully. "As it was an ad hoc analysis and wasn't pre-defined, this may be a chance finding," he said. "It would be important to confirm this in other datasets before making recommendations. The benefit could, however, be even greater in less nourished populations. These findings were only apparent after 10 years, so this should encourage others to look at this with this timeframe in mind."
Lucía Iglesias Vázquez, a researcher and lecturer in nutrition and public health, also urged caution. "This is a post hoc analysis, meaning it was not the original primary objective of the trial, and the observed effect sizes are modest. Most participants had relatively adequate Vitamin D levels at the start of the study, so the results may not be generalisable to populations with more severe deficiency. Overall, the study reinforces the hypothesis that prenatal nutrition may influence child neurodevelopment, but further studies are still needed to determine which levels and timing of supplementation might have the greatest clinical impact."
Professor Asma Khalil, professor of obstetrics and maternal medicine at City St George's, University of London, added: "In real-world terms, this study adds to the evidence that vitamin D during pregnancy is important, but it does not, by itself, justify changing clinical recommendations. The findings are interesting and add to growing evidence that Vitamin D is important in pregnancy, but they do not mean that taking very high doses of Vitamin D will make children 'smarter'. Pregnant women should continue to follow existing medical advice on Vitamin D supplementation and speak with their healthcare professional before taking higher doses."
The NHS currently recommends that all pregnant and breastfeeding women take a daily 10-microgram Vitamin D supplement to maintain maternal bone health and ensure the baby receives enough for healthy development of bones, teeth, kidneys, heart, and nervous system.
