Overweight as defined by the body mass index (BMI) rating scale may not be linked to an increase in death when considered separately from other health issues, according to a new study. According to CNN, the study challenges the commonly held belief that being overweight is associated with a higher risk of mortality.
BMI, a calculation that measures a person's body fat based on their height and weight, categorizes adults into different degrees of body fat. According to the US Centers for Disease Control and Prevention, individuals with a BMI between 25 and 29.9 are considered overweight, while those with a BMI between 18.5 and 24.9 are classified as having a "healthy" or "normal" weight. A BMI of 30 or higher is considered obese.
Experts Highlight Limitations of BMI in Assessing Health Risks
The study, conducted by researchers from the Rutgers Robert Wood Johnson Medical School in New Brunswick, New Jersey, analyzed data from over 554,000 non-pregnant Americans aged 20 and older. The researchers compared BMI levels with deaths that occurred over a period of 20 years.
The findings revealed that the risk of death increased by 18% to 108% for most people with BMI levels higher than 27.5, with the risk rising as weight increased in a U-shaped curve. However, the study found no significant increase in mortality for adults over the age of 65 with a BMI between 22.5 and 34.9, which includes those with normal weight, overweight, and obesity.
Experts not involved in the research caution that the study's limitations make it difficult to determine if the findings are solely due to BMI or other factors. They emphasize that the study only shows an association, not causation. Factors such as quality of life and the development of comorbidities like diabetes or heart disease were not fully explored in the study.
Furthermore, the study highlights the importance of considering additional measures of health risk beyond BMI. Waist circumference, other measures of adiposity (fat), and weight trajectory should be taken into account to obtain a more comprehensive understanding of an individual's health.
Study Shows U-Shaped Relationship Between BMI and Mortality Risk
While being overweight may not necessarily lead to an early death, experts emphasize that it can contribute to an increased risk of chronic diseases. Conditions such as diabetes, cardiovascular disease, renal failure, and blindness are more prevalent among those with higher BMIs.
The study underscores the need to move beyond BMI as the sole measure of health and to include waist circumference as part of health assessments. Deep fat that surrounds the body's organs, known as visceral fat, has been linked to various health risks, including dementia, heart disease, frailty, and early death.
Medical organizations, such as the American Heart Association and the American Medical Association, have also acknowledged the limitations of BMI and called for a more comprehensive approach to assessing an individual's health.
While the study adds to the ongoing discussion surrounding BMI and its limitations, experts emphasize that the impact of excess weight on the body and the risks associated with it are well-established. The focus should be on improving people's quality of life and happiness through relevant interventions at various stages of life.
