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It's no surprise that many moms-to-be think a lot about what they eat. For some women, intense cravings and big appetites lead to concerns about too much weight gain during pregnancy. Well, now, new research indicates there may be a direct link between a mother's diet during pregnancy and her child's future eating habits and weight. NPR's Allison Aubrey reports.
ALLISON AUBREY, BYLINE: Kim Cooper, who's the mom of two young boys, recalls precisely what she craved during her pregnancies.
KIM COOPER: It's funny, with my first - with my older son - lemon squares. I wanted them and was making them all the time, and eating them.
AUBREY: So sugar.
COOPER: Yes. And the lemon, the tartness.
AUBREY: Now, Cooper says, don't get her wrong; she also ate plenty of healthy things - salads, beans, avocados. So she did not gain too much weight. And now, almost three years later, she says her son is a healthy weight, and he knows what he likes to eat.
COOPER: He definitely has the same taste buds. So anything that I like, he generally likes. So that could be a pretty big indication of what I eat is what he now likes.
AUBREY: Now, it doesn't always work out this way. But new studies suggest there is a fascinating and somewhat complicated relationship between a mom's diet during pregnancy and her babe's behaviors. It's been known for a while that if a mom-to-be is overweight when she conceives or gains too much weight during pregnancy, her child is more likely to become overweight, too. Physician David Ludwig, of Harvard, says this is well-established.
DR. DAVID LUDWIG: Increasing degrees of maternal weight gain during pregnancy consistently increase the risk of that child being obese.
AUBREY: So the question is, why? Is it becomes mom and baby have the same genes, or is it that if a mom eats an unhealthy diet, so do the kids?
LUDWIG: Children and mothers share many factors that could promote obesity, such as genes or environment.
AUBREY: And this is likely part of the explanation. But Ludwig's latest research suggests it's more complicated. It often happens that within the same family, you can have one sibling who's overweight while brothers and sisters have no weight problem at all. And when Ludwig looked into why, he discovered that the difference in how much weight a mother gained from pregnancy to pregnancy predicted which of her children would be heavier. He looked at more than 40,000 moms and found, for example, if a mom gained more during her second pregnancy compared to her first, then her second child was more likely to be overweight by age 10. So this shows there's more than genes at work here.
LUDWIG: Correct. And the importance of that is that genes are - at least, at this stage - not modifiable whereas diet and pregnancy weight gain are.
AUBREY: So if you want to protect your babe-to-be from the risk of obesity, new research suggests that what moms eat in the last three months of pregnancy may be key. Here's Yale researcher Tamas Horvath.
TAMAS HORVATH: It appears to us, at least, that by changing the diet in that period of development, you will have an impact on development of vulnerability to obesity.
AUBREY: Horvath says in his study, when pregnant mice were fed a high-fat, high-calorie diet, the brains of their pups changed. The diet rewired the part of the brain that's critical to regulating appetite. And this was true of the offspring of mice moms who weren't obese, and only were fed a high-fat diet during lactation, a period that corresponds to the third trimester of pregnancy in humans.
Now, it's not clear that it works exactly the same way in humans. But remember mom Kim Cooper, who told us that despite a few lemon squares, she did eat well towards the end of her pregnancy.
COOPER: More salads and more protein - probably more protein. I don't think - added that to my diet.
AUBREY: And this healthy pattern of eating has likely influenced her son for a lifetime.
Allison Aubrey, NPR News.
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