According to a new study by led by the Universities of Bristol and Oxford, even moderate exposure to alcohol in the womb (1-6 drinks per week) can negatively affect a child’s IQ.
Fetal Alcohol Exposure and IQ at Age 8
Previous research on the effects of moderate alcohol consumption during pregancy and child IQ led to inconsistent and conflicting results, likely because it was difficult to isolate lifestyle and social factors from the equation. Some of the previous research even seemed to indicate that moderate drinking had a positive effect on child IQ. However, because these studies were based on observational evidence, they were affected by the effect that mothers who drink moderately (1-6 drinks per week) are usually well-educated, are less likely to smoke, and have a better than average diet – all factors linked to higher child IQ.
Unlike previous observational studies, this study studied genetic variation and the link to IQ in order to control for lifestyle and social factors. What the study found was that certain alcohol metabolising genes found in the 4,167 children studied could be strongly linked to a lower level of IQ at the age of 8. Fetuses with these genetic variants were slower metabolisers of alcohol, whereas fetuses without these genetic variants were fast” metabolisers of alcohol. For each genetic variant the fetus possessed, the children had on average 2 fewer IQ points.
This effect was only found in children whose mothers were moderate drinkers (1-6 drinks per week). The results appear to strongly indicate that the fetal exposure to alcohol was responsible for the differences in IQ.
The main author of the report, Dr. Sarah Lewis summarized the findings by pointing out that this study indicates that moderate alcohol consumption that was previously thought to be harmless generated detectable differences in child IQ. These differences were based on metabolic markers that affected the ability of the fetus to process alcohol – meaning that lower the fetus’s ability to clear alcohol from their system, the lower the IQ.
All the more reason to abstain from alcohol completely – especially during pregnancy.
Link to Study: http://dx.doi.org/10.1371/journal.pone.0049407