Part III. Obesity AnnetteBoogerd,MS,RD,LD,JohnAlverdy,MD, FACS,SeemaKumar,MD,DianeL.Olson,RD, CNSD,andW.F.Schwenk,MD,CNSP If we could give every individual the right amount of nourishment and exercise, not too little and not too much, we would have found the safest way to health. Hippocrates, c. 460-377 BC I t may seem enigmatic to discuss malnutrition, ie, inadequate caloric intake, and obesity, ie, excessive caloric intake, in the same sentence. However, in industrialized nations the most common form of malnutrition is obesity. 1,2 The World Health Organiza- tion estimates that half of the world’s population, approximately 3 billion persons, have some form of malnutrition. 3 Malnutrition is imbalance in consumption of macronutrients and micronutrients needed for optimal health. 3 Despite excessive calorie intake, vitamin and mineral deficiencies may occur. A survey of studies sponsored by the United Nations reveals that 1.1 billion persons suffer from hunger, while another 1.1 billion consume excessive calories, resulting in negative health consequences. 3 In the United States, an estimated 97 million persons, representing 54.9% of the population, are overweight or obese, 4 and obesity rates have increased from 12.8% in 1962 to 22.5% in 1994. 5,6 Obesity is also the most widespread and severe nutritional problem in children in the United States. 7,8 The number of overweight children and adolescents in the United States increased by 30%, according to two National Health and Nutrition Examination Surveys, NHANES II (1976- 1980) and NHANES III (1988-1994). This trend toward increased body mass relative to height among children and adolescents over the last 30 years has been observed in the United Kingdom and Western Europe as well. Among children aged 6 to 17 years, 22% have a body mass index (BMI) greater than the 85th percentile, and 10.9% have BMI greater than the 95th percentile, 9 where BMI is defined as weight in kilograms divided by height in square meters (kg/m 2 ). Prevalence varies greatly by ethnic group, with Hispanic and Native American children of both sexes and Dis Mon 2002;48:725-42 0011-5029/2002 $35.00 + 0 62/1/130135 doi:10.1067/mda.2002.130135 DM, November 2002 725