But the concept is crucial. In fact, if you take away just one thing from the hundreds of issues we’ve discussed on this blog, let it be this: the connection between weight and health is VERY tenuous.
A study published today in PLoS Medicine confirms the notion that where you store excess weight is much more important than how much excess weight you carry. In the study, Claudia Langenberg and colleagues report that an elevated waist circumference (a marker of abdominal obesity) is associated with greater risk of type 2 diabetes, independently of body mass index (BMI). In other words, whether you are “normal weight”, “overweight”, or “obese” by BMI standards, having a big belly puts you at increased risk of diabetes.
Are these findings surprising? Not even close.
In fact, back in 2007, I published a study with Drs. Janssen and Ross in the journal Diabetes Care (read in full here), which was the first to clearly demonstrate that even after you account for your BMI as well as common clinical markers, those that are apple-shaped (elevated waist circumference) carry a significantly higher risk of diabetes.
Another study published in the New England Journal of Medicine in 2008 demonstrated that an elevated waist circumference predicts greater risk of death from all causes regardless of BMI level. Based on a ~10 year follow-up of about 360,000 Europeans, the authors of this study found that for a given BMI, an increase in waist circumference of 5cm was associated with a 13-17% increased chance of death in both men and women
The new results by Langenberg et al, along with countless prior studies, are in complete agreement with current clinical guidelines which recommend that physicians measure waist circumference along with BMI to assess a patient’s risk of disease.
Thus, if your waist circumference is greater than 102cm (men) or 88cm (women), you may be at risk of disease and premature death even if you are at a healthy weight. Conversely, if your BMI is in the overweight or obese range, but your waist circumference falls below the above cutpoints, you may not have much to worry about.