Vitamin D During Pregnancy, Infancy Can Reduce Aeroallergen Sensitization

Vitamin D supplements taken during pregnancy and infancy may help to reduce the high childhood allergy rate, a new study has claimed.

Cameron Grant from the University of Auckland in New Zealand showed for the first time that vitamin D supplements prevent allergy sensitization to house dust mites in children. He believes vitamin D supplements may also help prevent asthma developing in young children. "In our clinical trial of vitamin D supplementation during pregnancy and infancy, we showed that when these supplements were given to the mom at 27 weeks gestation, and then continued in her child until the child was six months old, they prevented sensitization of the child to house dust mites (measured when the child was 18 months old).

Based upon a careful review of the records of the children's visits to their family doctor, it was noted that vitamin D supplementation reduced the proportion of children making primary care visits which their family doctor thought were due to asthma," Grant said. This is the first study to show that correcting poor vitamin D status during pregnancy and infancy might prevent childhood asthma, he said. "An interesting aspect is that the effects we saw were measured a year after the vitamin D supplementation was stopped," said Grant.

This implies that vitamin D caused some change in the child's immune system as it was developing in utero and during early infancy which then resulted in differences in the immune response to house dust mites at age 18 months, he said. Early life events, including those before birth, can influence a baby's later sensitivity to allergens. "Vitamin D receptors are present on many immune cells and so vitamin D can affect how the immune system works," said Grant.

"In theory maintaining normal vitamin D status when that sensitivity is developing late in pregnancy and early in infancy, could prevent later allergy sensitivity in the child," he added. The findings were published in the journal Allergy.

We recommend discussing these findings with your Ob/Gyn and pediatrician to determine the appropriate dose of Vitamin D for you and your child.

Exclusive breastfeeding is associated with reduced cow's milk sensitization in early childhood

Although breastfed infants have consistently been reported as having fewer infections and respiratory morbidity during infancy, no previous studies have reached a definitive conclusion as to whether breastfeeding is an effective strategy to prevent allergic diseases. This study aims to investigate the relationship between exclusive breastfeeding and sequential changes of several biomarkers of allergy, such as absolute eosinophil count, Total IgE level, and specific IgE level during the first 3 years of life.

This is an unselected, population-based study that is part of a prospective birth cohort called the PATCH (Prediction of Allergy in Taiwanese Children). Blood analysis was performed at ages 6, 12, 18, 24, and 36 months. Clinical records of breastfeeding and detailed questionnaires regarding to allergic diseases were also obtained. Analysis comparing exclusive breastfeeding for at least 4 months with those for less than 4 months and those partially breastfed showed a decreased risk of sensitization toward cow's milk protein up to the age of 2 years. In addition, although not significant, children of the exclusive breastfeeding group showed a trend of lower absolute eosinophil counts (a cell associated with having an allergic reaction) than their counterparts at all ages, and a lower Total IgE level (the protein involved in causing allergic reactions) at the age of 3 years. In short, results of this study suggest that exclusive breastfeeding is associated with a reduced risk of cow's milk protein sensitization during early childhood.

These findings, while preliminary, are exciting, as they demonstrate lifestyle changes that may help to prevent children from developing certain types of allergies. Please keep in mind, it is important to discuss this information with your own and your child’s healthcare providers before implementing changes to make sure they are the right choice for you and your family.

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