Obesity is a complex problem—the result of geography, economics, culture, class, personal choice and personal genetics—and the combination of these factors has led to more than a third of American adults being considered obese. And here's another factor in this equation: journalist Kristin Wartman writes in the New York Times that new research is showing how diets of pregnant and breast-feeding women can bias their kids towards fatty foods. When expectant or new mom's fill their diet with junk food, she says, it can affect their baby's brain's chemical reward pathways and set the babies up to seek more of the same.
The tastes you grew up with, the researchers say, tend to stick with you. “This early exposure leads to an imprinting-like phenomenon such that those flavors are not only preferred but they take on an emotional attachment,” says psychologist Gary Beauchamp. Pretty much everything you do affects the structure of your brain, and food is no different. If those foods you're exposed to as a child—either in the womb or through breast milk—are energy-dense foods, like many junk foods, your brain will adapt to those foods. Wartman:
Mothers who were fed foods like Froot Loops, Cheetos and Nutella during pregnancy had offspring that showed increased expression of the gene for an opioid receptor, which resulted in a desensitization to sweet and fatty foods. “The best way to think about how having a desensitized reward pathway would affect you is to use the analogy of somebody who is addicted to drugs,” Jessica R. Gugusheff, a Ph.D. candidate at FoodPlus and the lead author of the study, wrote in an email. “When someone is addicted to drugs they become less sensitive to the effects of that drug, so they have to increase the dose to get the same high,” she wrote. “In a similar way, by having a desensitized reward pathway, offspring exposed to junk food before birth have to eat more junk food to get the same good feelings.”
So, add another layer to the complexities of obesity, and the realization that though junk foods tastes pretty good to all of us, for some it takes a little more to hit the sweet spot.
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