Study Discounts Formula Feeding-Obesity Link One of the arguments made in favor of breast-feeding is that breast-fed babies are less likely to grow up to be obese adults than babies who are formula-fed. A new study says that's not the case.
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Study Discounts Formula Feeding-Obesity Link

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Study Discounts Formula Feeding-Obesity Link

Study Discounts Formula Feeding-Obesity Link

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This is DAY TO DAY. I'm Alex Cohen.

If you're a new parent, there is a good chance you're facing a tough choice: breast or bottle. Those who prefer mother's milk claim there are many health benefits that make it a better option than formula. Some say breastfed babies are less likely to grow up to be chunky kids and obese adults.

But new research shows that claim may not be true. Doctor Sydney Spiesel sees lots of moms and infants in his pediatrics practice in Woodbridge, Connecticut. He writes the "Medical Examiner" column for the online magazine, Slate, and he is a regular contributor to DAY TO DAY. Welcome back, Syd.

Dr. SYDNEY SPIESEL (Columnist, Slate Magazine): Thank you. Always good to be here.

COHEN: First up, can you explain the basic line of thinking here, why some people think that breast milk might make babies kind of head on that path to becoming slimmer kids and, later on, adults.

Dr. SPIESEL: It was believed that especially later in nursing that there might have been sort of more calories that kids could simply take in from formula than they could from breast milk. That might have been the explanation.

COHEN: Syd, tell me a little bit about the findings in this new study regarding breast-feeding versus formula.

Dr. SPIESEL: Well, it was a huge study of 35,000 registered nurses whose mothers were available to answer the question about how these nurses had been fed when they were infants. What was found is that in terms of their ultimate question, whether they were overweight or underweight or normal weight, it didn't matter whether they had been formula-fed, breastfed for a week or exclusively breastfed for a month. That played no role in the ultimate outcome.

COHEN: And there were no differences between - what about between childhood and adulthood?

Dr. SPIESEL: Well, there was a small difference there. If you look at the study, when kids were about five years old, the formula-fed babies - babies who have been formula fed - were a little bit chunkier, were a little bit heavier than the babies who had been breastfed. But apparently that difference just disappears over time.

COHEN: Now, I'm sure some mothers might say, okay, if it doesn't make a difference, it's a lot easier to feed formula. I'm going to go that route. What are your thoughts on that?

Dr. SPIESEL: Well, whether a baby turns out to be an obese adult would not be a very strong argument. There might be many other arguments in favor of breastfeeding that are very different. I mean, for many women, but not all, not all, there's a kind of wonderful warmth that comes about in their relationship with the baby as they're feeding the baby.

Some mothers actually don't do as well and don't enjoy feeding. And for me the bottom line is the essence of breastfeeding - the essence is not a nutritional one. The essence of feeding a baby is not a nutritional one. The essence of feeding a baby is, in some broad way, how the baby does. And that I think is going to depend very much on how positively the mother feels about breastfeeding. That makes a tremendous difference to me.

COHEN: Syd, when I first took a look at the study, the first thing that struck me was that - kind of a shock that parents were so concerned about how their kids might turn out in terms of their weight, that they were willing to start right at the very get-go controlling what they ate. Do we need to kind of worry at all about, you know, how much parents' concerns about childhood obesity, adult obesity, would translate into their kids growing up with, you know, possibly developing eating disorders.

Dr. SPIESEL: Yes. I'm always worried about that. And by being so worried about this stuff, we can really make kids tremendously anxious or tremendously focused on feeding. And it's one of the reasons that I have mixed feelings. I wish he had more research that would show exactly what are the effects, positive and negative, about our well-intended interventions around diet and around encouraging kids to think about what they're eating and not eating.

COHEN: That's opinion from Dr. Sydney Spiesel. He's a pediatrician, and you can read his "Medical Examiner" column at Thanks for being with, Syd.

Dr. SPIESEL: Thank you.

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