A Measure of Health

A closer look at BMI’s usefulness

Do you know your BMI?  Also known as Body Mass Index, it’s a tool often used by dietitians and doctors to categorize ones weight as normal, overweight, underweight or obese.  However, it’s been criticized for mislabeling individuals as overweight or obese because it doesn’t distinguish between fat or lean body mass like muscle; it’s simply a measure of weight for height obtained by dividing weight by height squared.  Athletes or fit folks for example, can be misclassified as having an unhealthy weight using BMI since they weigh more because of their muscle mass.    

A study published in The Journal of the American College of Cardiology suggests that BMI may indeed be a useful tool for measuring health after all—specifically heart health.  Researchers compared BMI with measurements from dual-energy x-ray absorptiometry (DXA scan), a detailed test that distinguishes between lean and fat tissue.  Over 2,800 children (10 years old) were assessed.  Eight years later BMI and measurements of heart health such as blood pressure, cholesterol and triglycerides were examined as well.  Investigators found these markers to be elevated when BMI was elevated at age 10, suggesting that both tests yield relevant results in the context of coronary heart disease.  BMI however is much less expensive and can be calculated in less than a minute!

According to the Centers for Disease Control and Prevention, Heart Disease is the leading cause of death for both men and women in the U.S.  Risk factors include elevated blood pressure, cholesterol, smoking, overweight and obesity.  This study highlights the importance of knowing your BMI and perhaps giving the measure more weight when it comes to grading your overall health.