Maybe Kid Sisters Can Prevent Obesity?

An intriguing new longitudinal study finds that children with a younger sibling born while they are two to five years old are much less likely to develop obesity. Thankfully, reporters are resisting the temptation to proclaim that kid sisters (or brothers) can prevent obesity.

The study, published in Pediatrics, followed 697 children recruited from ten sites in the U.S. and found that children who did not experience the birth of a sibling by the time they entered first grade were approximately three times more likely to have obesity. Senior author Julie Lumeng commented:

We have very little information about how the birth of a sibling may shape obesity risk during childhood. This study is believed to be the first to track subsequent increases in BMI after a child becomes a big brother or sister. We need to further study how having a sibling may bring even subtle changes such as mealtime behaviors and physical activity.

Elsie Taveras, Chief of Pediatrics at Massachusetts General Hospital, commented on the study, saying:

The study was excellent and really well done. But without research on the mechanism, which was beyond the scope of the study, it’s too early to give any advice or propose a program to help the older siblings maintain a healthy weight. I don’t think this finding should be a factor in family planning.

Thank goodness she clarified that last point.

Click here to read the study. here to read more from Reuters, and here to read more from HealthDay.

Kid Sister, photograph © charamelody / flickr

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March 13, 2016