Extent of the problem
Childhood obesity has already emerged as a global epidemic. An estimated 22 million children under five are estimated to be overweight worldwide.¹ From the two national surveys of 7-13 y-old Canadian children between 1981 and 1996, the prevalence increased from 11 to 33% in boys and from 13 to 27% in girls for overweight and from 2 to 10% in boys and from 2 to 9% in girls for obesity over the 15 years.²

The problem increasingly extends into the developing world in which under-nutrition is still prevalent. For example, the 2001 national survey of ...