Twin babies are seen in this photo. (123rf)
Low levels of vitamin D in pregnant women and their babies may weaken children’s immune function and increase their vulnerability to allergies later in life, a South Korean study has found.
The Korea Disease Control and Prevention Agency said Monday that researchers tracking children in a birth cohort for respiratory and allergic diseases identified a link between vitamin D deficiency at birth and heightened allergic responses in childhood.
The study, conducted by a team led by Professor Hong Soo-jong at the National Medical Center, examined 322 children aged three to nine. Researchers assessed their sensitivity to common airborne allergens, including dust mites, pollen and pet dander.
Blood tests showed that children who were sensitized to multiple allergens had higher levels of inactive vitamin D in their systems — a form that cannot be readily used by the body.
These children also showed increased levels of immune response markers associated with allergies, as well as proteins linked to oxidative stress. Higher levels of inactive vitamin D were correlated with elevated markers of immune inflammation, the researchers said.
Further analysis found that children with lower vitamin D levels in cord blood at birth tended to have higher levels of inactive vitamin D metabolites later in childhood.
The findings suggest that vitamin D status at birth may influence how the immune system develops, potentially affecting allergy risk.
“In children sensitized to multiple allergens, immune inflammation, oxidative stress and abnormalities in vitamin D metabolism can occur together,” Hong said. “This suggests that vitamin D levels at birth may play a role in shaping immune responses in childhood.”
Health officials said the results highlight the importance of maintaining adequate vitamin D levels during pregnancy.
“Keeping sufficient vitamin D levels in pregnant women is an important foundation for establishing immune balance in children,” said Kim Won-ho, head of the chronic disease research division at the National Institute of Health.
He advised pregnant women to manage vitamin D levels through moderate sun exposure — about five to 30 minutes at least twice a week — and dietary supplements if needed.
hnpark@heraldcorp.com
