Body Mass Index Flawed?
Friday August 18, 2006
Obesity is almost universally defined by body mass index, or BMI. And BMI is used to predict heart disease and other chronic diseases. A BMI figure of 25 to 29.9 is overweight and a BMI of 30 is obese. Yet the August 19th Lancet has an analysis of 40 studies involving 250,000 people showing that those with a low BMI had a higher risk of heart attack than those with high BMI—the exact opposite of what we would expect. How could this be?
Although BMI is based on weight and height, it doesn’t distinguish fat from muscle. An athlete may have a high BMI because muscle is heavier than fat. And BMI may not be a good indicator of risk in seniors since weight loss is as likely to be caused by a reduction in muscle and bone mass as a reduction in fat.
A better way to measure obesity and health risk is the waist-to-hip-ratio, which takes into account body shape and fat deposits, where being pear-shaped is healthier than being apple-shaped. Abdominal fat is considered to be the most dangerous type of fat since it lies deeper in the body, surrounding vital organs, putting us at greater risk of heart disease, insulin resistance and diabetes.
Comments
This makes more sence to me than the way it has been done for years…Thanks for the true insight of BMI
My BMI is 29. I look about 40 pounds lighter than I am. I have an hourglass figure. I’m at the gym five days a week. My waist hip ratio is .80. Nobody thinks I’m overweight. People don’t believe me when I tell them how much I weigh. But the government considers me overweight, and every gym or diet plan automatically assumes I am in order to sell me something. (E-diets will tell you you’re overweight just on your height and weight alone.) According to the BMI George Bush is overweight and Arnold Schwarzenegger is obese. That gives you an idea how inaccurate the BMI is. A lot of people still consider it as gospel though.