About 17 percent of children in the United States are obese, according to federal health statistics. That's a sobering statistic for parents to ponder as September marks National Childhood Obesity Month.
"One in five children in the U.S. enter school overweight or obese. Many kindergarteners with normal weight end up gaining too much weight during elementary school," said Ashlesha Datar, a senior economist and director of the Program for Children and Families at the USC Dornsife College of Letters, Arts and Sciences.
"It turns out excess weight during early childhood is not just a passing phenomenon that disappears once growth spurts occur. Excess weight in childhood substantially increases the risk of remaining obese into adolescence and adulthood. Because obesity is linked with serious health consequences, addressing excess weight gain in early childhood should be a top priority.
The emphasis of most early childhood programs is on cognitive and socio-emotional readiness, she noted.
"Childhood obesity may decrease if entering school 'ready to learn' included the formation of good habits that promote healthy body weight. Reinforcing healthy behaviors in early childhood can create wholesome habits as children transition through adolescence and adulthood," Datar said.
Americans devour sugar
Americans consume an average of 22 teaspoons of sugar sweeteners every day, which is over twice the recommended limits set by the American Heart Association and the World Health Organization.
"Excessive sugar consumption has been linked to obesity, Type 2 diabetes and heart disease. The abundance of high-sugar foods and food cues in our environment (such as the sight or smell of chocolate chip cookies) can prime us to eat beyond our energy needs by stimulating brain pathways that control reward, attention and motivation," said Kathleen Page, an assistant professor of medicine at the Keck School of Medicine of USC.
"Studies in animals suggest that diets high in sugar affect these brain pathways and can induce sugar craving-like behaviors. Understanding how sugar sweeteners affect brain pathways and eating behavior in people is critical to our efforts to reduce the rising rates of obesity, Type 2 diabetes and heart disease."
Memory and cognition
"Emerging findings reveal that excessive consumption of sugar and high-fat foods during childhood can have detrimental effects on memory and cognition," said Scott Kanoski, an assistant professor of human and evolutionary biology and neurobiology at USC Dornsife.
For example, he explained, the hippocampus, a brain region that helps people remember autobiographical events and navigation routes, appears to be particularly vulnerable to early life consumption of unhealthy food and drink.
Obesity does not exist on an island
Obesity is not an individual problem, according to Kayla de la Haye, an assistant professor of preventive medicine at the Keck School of Medicine.
"Our social networks influence what we eat, if we are active and, ultimately, how we manage our weight. The 'norms' in our day-to-day social networks, consciously and unconsciously, foster our views about what degree of overweight is healthy and normal.
"We have to tackle obesity prevention collectively in families, peer groups and organizations. We have to create social networks that support healthy eating, activity and weight."
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