MINNEAPOLIS (WCCO) — More than one third of American children are overweight or obese, and a new study shows signs of this health problem can be detected earlier than you might think.

Researchers followed nearly 8,000 children, and almost half of the kids who were obese at 14 were already overweight when they were just 5 years old.

READ MORE: Puppy Who Was Inside Stolen Vehicle In St. Paul Reunited With Owner

Pediatricians say taking simple healthier steps when children are small is the key to preventing obesity.

READ MORE: Winter Flower Show

“It’s so easy to cut calories just by stopping juice in a child’s diet, giving low fat milk after two instead of whole milk, getting your kids active,” said Dr. Dyan Hes of Gramercy Pediatrics in New York. “Children should have one hour of physical activity a day.”

MORE NEWS: COVID In Minnesota: 57 More Deaths Added To State's Toll; Positivity Still Inching Down

The study also found that babies born large are at the highest risk of becoming obese by high school.