Obesity has become a worldwide epidemic that is not restricted to adults. Unfortunately, child and adolescent obesity has become a major public health problem. Childhood obesity refers to children and youth between the ages of 2 and 18 years who suffer an excess of body fat reflected through their body mass index (BMI).

BMI is a weight-to-height ratio, and is calculated by dividing body weight in kilograms by the square of height in metres (kg/m²). According to the International Obesity Task Force, at least 155 million of the world’s children aged 5–17 are overweight. An additional 22 million children under the age of 5 years are also affected (International Obesity Task Force, 2004).