There is a difference between an overweight child and an obese child. An obese child is described by health experts as one who weighs more than 20 percent of his ideal weight. This extra weight can be dangerous. Centers for Disease Control and Prevention data show that overweight adults are at an increased risk for heart disease, high blood pressure, stroke, diabetes, some forms of cancer, and gallbladder disease. It should be noted that there are social complications that obese children are likely to suffer such as peer-criticism and the constant schoolyard teasing that can result in depression or violence.
Parental denial is a big issue.
If he or she is active, make a list of what physical activities the child does during the day, because he or she may just ride a bike across the street to go play video games.