Yes, while breastfeeding is the optimal first food for a baby, it's not as simple to say that it will protect all children from becoming obese. Recent studies show that factors such as whether a child's mother is obese, the quality of her milk and the socio-economic conditions a baby is born into also have an influence. This is according to Jessica Woo and Lisa Martin of the Cincinnati Children's Hospital Medical Center in the US, who reviewed relevant breastfeeding studies in Springer's journal Current Obesity Reports.
Because it is notoriously difficult to treat obesity, research is increasingly geared towards preventive strategies. One such method is the advocacy of breastfeeding, as human milk contains all the nutrients and immunity support to help a baby develop optimally.
More than 80 observational studies done in the past 20 years all concluded that the odds of an infant who drank breast milk becoming obese is 12 to 24 percent less than for drinkers of formula milk. This protection increases the longer and the more exclusively someone was breastfed. Woo and Martin however note that research should now move beyond observational studies, as these are not always precise, and often rely strongly on the mothers' ability to accurately recall the timing and intensity of their breastfeeding patterns.
The review shows that biological researchers increasingly study the link between maternal obesity and severely overweight children. They found that some components in the milk of obese and lean mothers differ, which therefore means its safeguarding ability on offspring varies from woman to woman. Human milk studies, work in probiotics, and research on the impact of maternal characteristics also highlight the protective value of having the right micro-organisms in the gut. Such micro-organisms seem to influence what and how much people eat. Children's food fussiness has also been found to be rooted in breastfeeding and their earliest experience of what they eat. It influences the chances of their choosing healthier food later on in life.
Woo and Martin suggest that there's more to the development of obese children than just the type of milk they consumed as babies. In the US, for example, the decision to breastfeed may be made by mothers who in any case pursue a healthy lifestyle.
"They have knowledge about healthy choices, and the time, income and social support to translate that knowledge into the non-trivial choice to initiate and continue breastfeeding, in order to accrue the many known benefits for their infant's and their own health," says Woo, who believes that educating mothers about healthy habits could appreciably reduce obesity in children, and also increase the wellbeing of women.
"The decision to breastfeed is strongly personal and closely linked with specific socio-economic and lifestyle patterns. Therefore, definitive epidemiologic evidence about the role of the feeding of human milk on obesity prevention may never be truly attainable," Martin notes.
Reference: Woo, J.G. & Martin, L.J. (2015). Does Breastfeeding Protect Against Childhood Obesity? Moving Beyond Observational Evidence, Current Obesity Reports. DOI 10.1007/s13679-015-0148-9.