This seems an odd and unexpected finding:
Children born to obese or very overweight mothers are at higher risk of having autism or developmental delays, new research suggests.
The study of more than 1,000 children found that the offspring of obese mothers had a 67 percent higher risk of autism than the children of normal-weight moms, and more than double the risk of having developmental delays, such as language impairment.
That sort of thing—“double the risk”—sounds huge. But the rarer a phenomenon is, the less big a deal such an increase would be in practical terms. For example, if the incidence of something is generally one in ten thousand, double the risk would make it one in five thousand.
Autism, of course, is more common than that, perhaps one in eighty-eight. It is not only still basically a mystery as to cause, but it’s a diagnosis that has lent itself to wild speculation about its genesis. When I was a child, the whole thing was blamed on cold, rejecting moms. Now that’s not considered the case at all. And the once-popular vaccination theory has been debunked, too, but that doesn’t stop a lot of people from believing in it. Now it could be blame-the-mother time again (at least in the popular imagination), only the new cause would be obesity.
Well, although it may be a contributing factor, it’s certainly not the cause: most autistic children do not have obese mothers, and most obese mothers do not have autistic kids.
The headline of the article emphasizes the obesity link, but buried in the text is something else quite interesting:
Indeed, other research published last week identified several spontaneous genetic mutations as the cause of a fraction of autism cases. Parents’ ages, especially fathers older than 35, were also associated with autism in those recent studies, published online in the journal Nature.