As the dietary habits of Koreans become more westernized, there are opinions that the standards for obesity should be raised. Experts opposed this, stating that raising the standards for obesity could reduce awareness of the condition.
Hong Jun-hwa, a professor at Eulji University School of Medicine, said on the 14th at the 'Korean Society for the Study of Obesity Spring Conference' held at the Grand Walkerhill Seoul, "Rather than relaxing the standards for obesity, we should maintain them to proactively create an environment for management and prevention." Professor Hong made this remark as a discussion panel on obesity diagnostic guidelines.
In the country, obesity is defined as a condition where excessive accumulation of fat damages organs and, consequently, leads to other diseases. However, when diagnosing obesity, the Body Mass Index (BMI), which is calculated by dividing weight by the square of height, is used instead of measuring the extent of fat accumulation. Evaluating fat accumulation requires significant time and expense, while BMI can be simply calculated by measuring height and weight.
In Korea, a BMI of 25 is used as a standard for diagnosing obesity. A BMI of 25 corresponds to a weight of 74 kg when considering the average height of adult Namsung men at 171.5 cm. If the BMI exceeds 25, it is classified as obesity, while a BMI of 23.0 to 24.9 is regarded as overweight or a pre-obesity stage. Professor Kim Yang-hyun of Korea University noted, "Most Asian countries use a BMI of 25 as the standard for obesity," adding, "This is lower compared to the standards of white-centered countries like the U.S. and Europe."
In fact, most western countries, including the United States and Australia, use a BMI of 30 as the standard for obesity. The World Health Organization (WHO) also suggested a BMI of 30 as a standard when it first established obesity criteria in 1995. Individuals classified as obese in Korea may be diagnosed as normal when they go to the United States.
The National Health Insurance Corporation presented research findings at the Korean Society for Health Education and Promotion's fall academic conference last year, stating that the standard for obesity among Koreans should be raised from a BMI of 25 to 27. They argued that a BMI of 27 or higher increases the risk of disease and mortality, and thus should be used as the standard for obesity.
The Health Insurance Corporation tracked mortality rates based on BMI for 21 years among 8.47 million adults who underwent health screenings from 2002 to 2003. The results showed that when the BMI is at level 25, the risk of mortality is low, and at a BMI of 29, the risk of mortality is more than doubled compared to previous ranges. Hypertension, diabetes, and dyslipidemia present a significant increase in risk at a BMI of 27, while coronary artery disease appears at a BMI of 29, and cerebrovascular disease at a BMI of 31. The Health Insurance Corporation concluded that the standard for obesity should be adjusted to a BMI of 27, considering all these factors.
If the BMI standard for obesity is raised, some individuals who were previously classified as obese will now be classified as merely overweight or normal, despite their physical condition remaining unchanged. This change in standards allows individuals to be categorized from patients to normals. From the perspective of the Health Insurance Corporation, this reduction in the number of obese patients could lead to a decrease in healthcare expenditure.
The medical community argues that the standards for obesity should not be tied to mortality rates but should instead be based on the risk of developing related diseases such as diabetes, hypertension, and sleep disorders. Professor Kim Yang-hyun stated, "According to the racial obesity standards proposed by the WHO in 2000, a BMI of 25 is appropriate for Asian countries," explaining, "This is because the incidence of related diseases significantly increases at a BMI of 25."
Professor Hong Jun-hwa also argued that considering the risks of obesity-related diseases in the country, the BMI standard should be maintained at 25. He cited China's case, emphasizing that each nation should maintain its own BMI standards based on its population and ethnicity. Professor Hong noted, "China initially applied a BMI standard of 30 for obesity and later lowered it to 28," explaining, "They set this standard based on research indicating when the risk of obesity-related diseases begins to increase among their citizens."
The need to introduce more accurate measures rather than just BMI for precise obesity diagnosis has also been raised. Professor Hong said, "To define obesity accurately, one should consider various standards including how much excessive body fat there is and how it is distributed, such as waist circumference or body composition analysis, and methods utilizing blood indicators such as insulin or low-density lipoprotein (LDL) may also be employed."