Obesity and Its Related Diseases in China: The Impact of the Nut ...

In addition, the ATP III criteria use fasting glucose as a marker for insulin resistance instead of insulin resistance directly measured by glucose clamp. Furthermore, the ATP III uses waist circumference as an index for central obesity instead of waist to hip ratio, and excludes the criteria of microalbuminuria. Thus it is more practical for clinical use and epidemiological studies.

Previous studies compared the classification of the metabolic syndrome by using these two definitions and observed that the agreement was high (86%) for the entire US population. However, prevalence of central obesity, as defined by the WHO criteria, was nearly twice higher than that defined by the ATP III criteria (68% vs. 39%) in the US population (87). Using either definition, the metabolic syndrome was common in US adults, about 25%. The prevalence was highest among Mexican-Americans (32%). The rate was slightly higher in men than in women in American whites. However, in African-Americans and Mexican-Americans, women had significantly higher prevalence than men (87, 88).

2.1.3 Asian-Specific Criteria for Overweight and Central Obesity

Recently, the widely used recommendations on classifying overweight and central obesity have been questioned with regard to their appropriateness for Asian populations. In 2000, the International Obesity Task Force recommended lowering the BMI cutoff points to 23 and 25 kg/m² to define overweight and obesity and lowering waist circumference threshold to 90 cm for men and 80 cm for women to define central obesity in Asians (89).

2.1.3.1 Overweight

Obesity is a condition characterized by excessive body fat, which raises the risk of adverse health outcome (90).