Monitoring the child's calorie intake, whether from breast milk or formula, is also important to maintain a healthy weight.
Deen explained that while the study also raises some important concerns about racial differences, it does not change the overall approach to obesity.
"What we are talking about are moderate prevalence rate differences among different ethnic groups," he said. "I don't think it helps me much as a practitioner if I know that one group of my patients has more obesity than another group.
"When I have a patient in front of me, my advice about healthy choices remains the same, regardless of what their race is."
Deen added that as rates of childhood obesity rise, changing kids' behavior towards food will become more and more crucial.
"I think we need to worry because there clearly is an epidemic of childhood obesity in the country," said Deen.
"The take-home message from this study should be that what we do with children, even in the early years of life, has an impact on their future."