Family Matters

Breastfeeding’s Role in Controlling Obesity Is Weakened

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Breastfeeding is no magic bullet against obesity, according to research that contradicts previously held beliefs about the scope of human milk’s capability.

“There’s a lot of other evidence out there to continue to support breast-feeding,” says the study’s lead author Dr. Richard Martin, a professor of clinical epidemiology at the University of Bristol in the U.K. “But in terms of breastfeeding reducing obesity, it’s unlikely to be effective.”

Martin worked with colleagues at Harvard University and McGill University in Montreal to assess 15,000 mothers in Belarus. The location was intentional — when the study began in 1996, breastfeeding was not a popular practice among Belarusian mothers. By separating the moms-to-be into two groups — one that gave birth at hospitals where staff received “Baby-Friendly” training designed to encourage breastfeeding, while the other delivered at hospitals that provided no extra support for the practice — researchers were able to create a “huge contrast” in a setting where breastfeeding rates were historically low. After three months, 43% of babies in the first group were exclusively breastfeeding compared to just 6% in the group that were born in hospitals that had no extra training.

The babies were followed up in 1997 — their first year of life — and again when they reached 6 ½ and 11 ½. The breastfed babies experienced fewer gastrointestinal infections, less eczema and higher IQ (they scored about 7 ½ points higher than their formula-fed friends at age 6 ½). There was no difference in dental cavities, allergies, asthma or rates of being overweight or obese.

(MORE20 Ways to Make Breast-Feeding Easier)

The latest report, published in the Journal of the American Medical Association (JAMA) marks the first release of data from the 11 ½-year old participants. Mirroring the earlier results, the researchers found no changes in weight and body fat between those who were breast-fed and those who weren’t. About 15% of the children in both groups were overweight, and 5% were considered obese.

Comparing body mass index (BMI) or measures such as waist circumference and skin thickness yielded “absolutely nothing that was statistically significant,” says Martin.

These results contradict previous studies that found breast-feeding cuts the rates of overweight or obesity among children. Experts believed the practice helped to lower obesity rates because it encourages babies to eat until they’re full as opposed to forcibly finishing bottles, even if they feel full. But these studies may have been documenting the effect of other, confounding factors on children’s weight.  Mothers feed babies based on how much weight the infants gain, as well as the toddlers’ eating habits, so it’s possible that some of the breastfed babies happened to be heavier to begin with, and that in turn prompted their mothers to feed them less.

In the current study, however, Martin hoped to avoid some of that potential bias by studying babies who were randomly assigned to be breastfed or bottle-fed. That allowed the researchers to control for other factors that could influence results — dietary choices, for example, or education levels.

“If you look at the characteristics of women who choose to breast-feed, they are very different from women who don’t,” says Martin. In the U.K., for example, 90% of women who attend college initiate breast-feeding compared to just 30% of women who don’t enroll.

The results strongly suggest that breastfeeding may not be the answer to the obesity epidemic, but Martin says the outcomes shouldn’t alter existing recommendations. For proper health and nutrition, the World Health Organization advises that babies be exclusively breastfed for the first six months, and for up to two years if needed.  The American Academy of Pediatrics suggests that moms breast-feed exclusively for about six months and continue breast-feeding to some extent for at least a year. But while 75% of U.S. mothers start out nursing their babies, only 44% are still doing so by the time their child is 6 months old.

(MOREIs the Medical Community Failing Breastfeeding Moms?)

If anything, the success of the Baby-Friendly initiative in the Belarusian hospitals should offer inspiration to U.S. birthing centers hoping to boost their own breast-feeding rates. Baby-Friendly hospitals encourage several practices that could make feeding easier, some of which I detailed in an article about ways to improve breastfeeding rates, including breast-feeding when the baby requires as opposed to on a schedule,  offering newborns only breast milk, as well as actively helping new mothers learn how to breast-feed:

Hospitals play a critical role in jump-starting a successful breast-feeding relationship, and those that are most committed to getting breast-feeding off to a good start — by encouraging babies to remain in their mothers’ hospital rooms where they can nurse on demand, for example, or breaking the tradition of sending new moms home with free formula samples in diaper bags paid for by formula manufacturers — are getting certified as “Baby-Friendly” facilities. But only 4% of hospitals can claim that distinction.

“I think it starts with hospitals, which need to support mothers to feel confident when they leave,” says lead author Cria Perrine, an epidemiologist at the Centers for Disease Control and Prevention (CDC) who focuses on infant feeding. “Employers and families have to be on board, and communities have to be comfortable with women breast-feeding in public. But hospitals are the front line. If women don’t even get started, there’s no way they can meet their goals.”

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What about the role of endocannabinoids in obesity? The NIH has lots on that. And endocannabinoids in breast milk. In fact why hasn't time done coverage on endocannabinoids? There are more cannabinoid receptors in the body than any other receptor type.


The key is "outcomes shouldn’t alter existing recommendations" as the study author says. Formula Feeder is right one study doesn't make it, but it is great that an ongoing research is continued. What is also great is that they are going beyond the borders of developed countries. I am from Belarus myself and happen to know breastfeeding situation there. Anything creating a positive vibe about breastfeeding helps. One thing that is a concern as far as the accuracy of the study is that Belarus is genetically not an obesity-prone country. I bet results might be different here in the US. Viktoriya from  


Ah!. Just what we were all waiting for - another breastfeeding article from Time. Hey, use Kate Upton on your next cover story about it. Doesn't matter whether she's a mom or not, because most people who read your mag. probably are not mom - and not even women. In Time's next life, get editors who are not part of the mommy brigade. They are boring.


I would like to recommend the free NAAFA Child Advocacy ToolkitSM (CATK) to assist you looking at programs. The total health of our nation's children is a serious responsibility.

The NAAFA Child Advocacy Toolkit shows how Health At Every Size® takes the focus off weight and directs it to healthful eating and enjoyable movement. It addresses bullying, building positive self-image and eliminating stigmatization of large children. Additionally, the CATK lists resources available to parents and educators or caregivers for educational materials, curriculum and programming that is beneficial for all children. It can be found at:


The WHO recommends a *minimum* of two years breastfeeding, not "up to".  They say there is no maximum, it's a decision for the mother and baby to make.  Biologically, Kathy Dettwyler's research indicates that anything between 2.5 and 7 years is normal.

FormulaFeeder 1 Like

As much as I appreciate that the media (and medical professionals) are stepping off the breastfeeding-as-magic-bullet-for-obesity-prevention bandwagon (because this is actually one of MANY studies which has found no statistically significant effect of infant feeding on later obesity), I find it highly ironic and a bit sad that we are so quick to assume the absolutism of one research finding. This is the problem with infant feeding research - heck, all research - these days: we speak and think in extremes. The fact is, PROBIT (the study that produced this outcome) is not a controlled, randomized experiment. All that the study design can really prove is whether BFHI work. They didn't "assign" one group to breastfeed and the other to formula feed; other research has shown that while BFHI certainly help raise breastfeeding initiation rates, they do not really alter longer-term breastfeeding rates. So there may still be fundamental differences in the families who engage in longer-term exclusive breastfeeding which can skew results one way or another.

A much better method is to use sibling pairs. We've only had two such studies, neither of which found any positive correlation between obesity reduction and breastfeeding. These studies were done years ago - and yet there's been no discussion of them in the multitudes of articles and "official" statements about how breastfeeding is the first line of defense against obesity, used to back up recent initiatives that limit access to formula and subtly restrict the choices of women. Instead, we take one rather vague finding from a study not even designed to look at obesity, and use to it throw the breastmilk out with the bathwater.

Maybe we can use this as a turning point in the conversation? Take a step back, and realize that these things are not black and white, and that to herald breastfeeding as a magical elixir has the potential to backfire and stymie efforts to make the world more breastfeeding-friendly?


1. We are largely an insulin resistance people today due to food chemicals. We do not make good insulin to lose weight

2. Food chemicals have made us insulin resistant and we stay fat

3. Dieting does not work because we are insulin resistant from food chemicals

4. You can eat very little and the weight does not come off because we are insulin resistant

 The key permanent weight loss is an insulin resistance diet See here