Low vitamin E in pregnancy may boost baby's asthma
risk
Children of mothers who take in too little vitamin E during pregnancy
may be at higher risk for asthma by age five, a new study suggests.
"The finding expands on previous research conducted by the same team. That work
found that two-year-old children whose moms had relatively low vitamin E intake
during pregnancy were more prone to wheezing -- even when they were otherwise healthy.
"This is part of a body of work that indicates that sufficient vitamin E intake
is probably important," said study lead author Dr. Graham Devereux, of the department
of environmental and occupational medicine at the University of Aberdeen in Scotland.
Devereux and his team reported their findings in the September issue of the American
Journal of Respiratory and Critical Care Medicine.
The authors focused on over 1,250 women who were pregnant and attending neo-natal
clinics in Scotland between 1997 and 1999.
Maternal dietary intake was assessed dating back to conception, as were medical
histories related to asthma, wheezing and related respiratory issues. The same information
was gathered for the children of these women up until the age of five.
Maternal intake of nutrients such as vitamin C, beta-carotene, magnesium, copper,
and iron during pregnancy did not seem to be correlated with an increased risk for
wheezing or asthma, the team found.
However, low intake of vitamin E during pregnancy was associated with a higher risk
among offspring for developing persistent asthma, beginning during the first two
years of life and continuing to at least until age five.
In fact, children born to mothers rated in the bottom 20 percent for prenatal vitamin
E intake were more than five times more prone to asthma as children born to mothers
in the top 20 percent.
Youngsters born to mothers with relatively poor vitamin E intake during pregnancy
were also at higher risk for developing persistent wheezing in their first 5 years
of life, the Scottish researchers reported.
The researchers stressed that a child's diet at age five appears to have no impact
on their asthma risk.
They pointed out that fetal airways are fully developed 16 weeks following conception.
That suggests that certain dietary deficiencies during pregnancy - particularly
early pregnancy - may heighten risks for childhood asthma. However, much more research
is needed to confirm that low prenatal vitamin E helps cause childhood asthma, Devereux
said.
For that reason, Devereux said, it is premature for women to take vitamin E supplements,
at any dosage, to help ward off asthma in their offspring.
Vitamin E is abundant in many staple foods such as green leafy vegetables, whole
grain cereals, vegetable oils, meat, and fish. The average adult's daily vitamin
E needs could be fully met if these foods were included in a balanced and healthy
diet, Devereux said.
"It should be strongly emphasized that women should eat healthily during pregnancy
and not take vitamin E supplements just because of this study," Devereux cautioned.
Dr. Arun Jeyabalan, an assistant professor in the division of maternal fetal medicine
at the University of Pittsburgh's Magee Women's Hospital, agreed. "This is an important
study because it is important to look at associations between nutrient intake, deficiencies,
and potential pregnancy outcomes," she said. "However, women should be very careful
about supplementation. Not all vitamins in high doses are good for anybody, and
further study is needed before advocating any kind of vitamin E supplementation.""