New research suggests that waist-to-hip ratio may be a more accurate indicator of health than body mass index (BMI). BMI is a widely used but controversial tool for screening obesity and overweight. In a study published in the medical journal JAMA Network Open, researchers examined the association between BMI and waist-to-hip ratio (WHR) and serious adverse health outcomes such as cancer, cardiovascular disease, and death. The study, which included nearly 400,000 individuals, found that WHR had the strongest and most consistent association with mortality, regardless of BMI.
The researchers argue that using WHR as a primary measurement of health could lead to better outcomes than BMI alone. They suggest that WHR offers a simple and accurate measurement, with lower values being better. Common guidelines recommend a WHR of less than 0.95 in men and less than 0.80 in women. However, other experts interviewed by Healthline disputed the claim that WHR is more accurate than BMI. They argued that BMI is still an important and reliable measurement, with Dr. Maya Mathur stating that BMI was just as good as WHR at predicting all-cause mortality for women.
BMI has been a widely used health indicator for decades, with a simple equation that calculates an individual's weight divided by their height squared. However, BMI has faced criticism for not accounting for differences in body type, ethnic variations, and fat distribution. Critics argue that individuals with higher muscle mass may be classified as overweight or obese despite their fitness level. Additionally, ethnic differences in BMI have been observed, with Asian individuals being more sensitive to changes in BMI than Caucasians. Furthermore, BMI does not consider the distribution of fat in the body, which can impact an individual's risk of chronic disease.
In contrast, waist-to-hip ratio takes into account the ratio of waist circumference to hip circumference. A moderate WHR is considered to be below 0.9 in men and below 0.85 in women, according to the World Health Organization. To measure WHR, individuals need to find the top of their hip bone and the bottom of their rib cage, then measure their waist circumference and hip circumference. The waist circumference should be smaller than the hip circumference.
While new research suggests that waist-to-hip ratio may be a simpler and more accurate indicator of health than BMI, other experts maintain that BMI remains an important and reliable measurement. The debate continues regarding the most effective tool for assessing weight and general wellness, and further research is needed to determine the best approach.