Researchers at the University of Michigan developed a longitudinal study that suggests that children with younger siblings are, most likely, to avoid child obesity.
The study investigated a possible association between the birth of a sibling and changes in the body mass index z-score (BMIz) during the first 6 years of the first born’s life. Scientists recruited around 697 children across 10 sites in the United States at the time of their birth.
The researchers studied the children and their siblings every 3 months and the mass and body index was studied when the child was age 15 months, 24 months, 36 months 54 months and in first grade.
The classification of the children was based on the timing of their sibling’s birth, doctors studied the association of weight and mass with a sibling based on statistics and age/weight numbers.
As a result of the study, doctors found that children whose sibling was born when they were 24 to 36 months or 36 to 54 months old, had a lower subsequent body mass index score compared to those children who didn’t experience the birth of a sibling by the time they were in first grade.
The children that had not experienced the birth of a sibling when they were in first grade had 2.94 odds of child obesity compared with those who did had a sibling.
Researchers assured they were not claiming that the birth of a sibling was directly the cause of weight loss, but that it associates and it is a topic that needs to be studied further.
Dr. Julie Lumeng, a pediatrician at the C.S. Mott Hospital at the University of Michigan said that “the possibility that seems more compelling is that if you have a younger sibling you are most likely to run around,” according to ABC News website.
So far, the explanation that seems more logical is that, having a younger sibling will allow children to have a playmate every day while they grow up, so both children endure in more active play.
Other theories play with the fact that having two kids leads to parents “loosing up” and directly meaning less restrictive feeding practices for children.
Source: ABC News