Scientists have pinpointed a potential risk factor for overweight and obesity early in life -- and it has to do with how many siblings a child has.
Researchers at the University of Gothenburg in Sweden, in addition to other researchers from other institutions across Europe, found that only children are more than 50 percent more likely to be overweight or obese, compared with children with brothers and/or sisters.
The study, published in the journal Nutrition and Diabetes, included 12,700 children ages 2 to 9 throughout Europe, who participated in the EFfects In Children and infantS (IDEFICS) study. The researchers had the parents of the children fill out questionnaires about the children's diets, exercise and play time.
The researchers found an association between being an only child and overweight and obesity after taking into account known risk factors like parental weight, weight at birth and gender. The researchers also found that only children were more likely to come from households with less education, less likely to play outside, and more likely to have TVs in the bedroom, though researchers that said even after taking these factors into consideration, the findings still held true.
"The excess risk of overweight among children without siblings was robustly observed even when considering behavioral mediating factors (playtime, screen time per day, dietary propensities for sugar or fat, parental attitudes towards food rewards and television in the child's bedroom)," the researchers wrote in the study.
It is important to note, though, that the study was conducted only in children from Europe.
Childhood obesity has risen at a startling rate in the last three decades, going from 7 percent to 20 percent between 1980 and 2008 in children ages 6 to 11, and from 5 percent to 18 percent in children 12 to 19 over the same time period, according to the Centers for Disease Control and Prevention.
For some tips for parents to fight childhood obesity, check out HuffPost blogger Marisa Moore's article here.
Also on HuffPost:
More:Only Children Overweight Only Child Obesity Only Child Weight Only Child Overweight Only Children Obesity
HuffPost Lifestyle is a daily newsletter that will make you happier and healthier — one email at a time. Learn more