Numerous studies have shown that breastfeeding decreases an infant’s risk of developing childhood obesity. However, some critics argue that this relationship may actually reflect genetic factors, rather than a direct effect of breastfeeding itself. Their reasoning is that parents with higher BMIs are less likely to start and continue breastfeeding their babies. Therefore, the apparent protective benefit of breastfeeding could simply be because infants born to healthier-weight parents are both more likely to be breastfed and less likely to become obese due to genetic reasons.
The majority of past studies examining the protective effects of breastfeeding against childhood obesity have had inadequate sample sizes to determine whether the mother’s BMI influences this relationship.
The authors of today’s study aimed to identify associations between breastfeeding and child BMI according to maternal pre-pregnancy BMI by analyzing data from the US Environmental Influences on Child Health Outcomes (ECHO) Program.
The ECHO program includes 69 diverse pediatric cohorts around the USA designed to evaluate early life exposures on pre-, peri, and postnatal outcomes, upper and lower airway disease, obesity, neurodevelopment, and positive health.
The researchers analyzed data from 8,134 dyads, including pre-pregnancy maternal BMI, infant feeding practices, and child BMI measured between ages 2 and 6.
Several covariates were included such as the child’s sex, maternal education, maternal age, use of nicotine products, and maternal race/ethnicity.
Before pregnancy, 2.5% of the mothers were underweight, 45.8% were a healthy weight, 26% were overweight, and 25.6% were obese. Approximately 17% of the mothers identified as Black, 58% white, and the rest either Asian, Hispanic, or multi-racial.
After adjusting for the above covariates, the authors found that breastfeeding, whether exclusive or not, for 6 months was associated with lower BMI among children whose mothers had a pre-pregnancy weight that was either healthy, overweight or obese.
Allison
It would be interesting to see if anyone followed up to why overweight or obese women stopped breastfeeding earlier than their “healthy” weight peers.
Both insulin resistance and thyroid conditions can lead to obesity and both can complicate breastfeeding, and both are often undiagnosed.
This may just be one more example of how fat shaming extends well beyond one’s actual weight.
IABLE
There is a wealth of research on reasons why people who are overweight or obese stop breastfeeding earlier than their peers with a ‘healthy’ BMI, such as decreased self efficacy and low milk production. Low milk production, as you point out, can be due to underlying insulin resistance that occurs for some people with elevated BMI.
Allison Harrison
That’s what I was getting out.
Rather than framing the original concept that people that are overweight don’t breastfeed as long, we serve our patients best to realize obesity may be a side effect of something else, which also can impact breastfeeding. That is the correlation that those outside of the lactation field are seeming to miss, such as primary care providers and OBGYNs