STATS ARTICLES 2006
Short, Diabetic, and Missing the Point
June 10, 2006
Rebecca Goldin, Ph.D
CNN stumbles over biological markers in study on diabetes
Being short causes diabetes, according to a piece on CNN titled “Short legs related to excess weight and diabetes,” which was based on a research article published in Diabetes Care this month. Previous research has suggested that short thighs are the problem — and that short-legged folk are more inclined to have heart attacks, too. One can only imagine people hovering over their candy bars, saying “can’t do much about being overweight, given these stumpy legs of mine...”
But the headline belies the science. Leg length is, according to the researchers, related to nutrition when young; bad nutrition stumps leg growth. And nutrition is also related to the subsequent diabetes. So leg length is just an indicator, like a sign on the road, that there may have been nutritional problems before puberty, which could have impact on diabetes and weight in middle age. But that doesn’t mean short legs assure you’ll get diabetes – approximately seven percent of the U.S. population has diabetes, according to the National Institute of Diabetes and Digestive and Kidney Diseases (part of the National Institutes of Health), and if your leg-to-height ratio is a full standard deviation below the norm, your risk increases to eight percent
Also, the study itself had far more conservative conclusions than CNN. While short-leggedness was correlated with being over weight for women, it was not so for men (there was a trend, but it was not statistically significant). As for diabetes, the only statistically significant increase in risk was for those with a lower leg-to-height ratio. In other words, being short or just having short legs did not correlate with diabetes enough to reach statistical significance. This suggests that the effect was small if any, especially considering the large number of people in the study. Perhaps a better title would have been “Bad nutrition leads to small leg-to-height ratio, diabetes” with an opening line pointing out that studies show a correlation between the two.
Being leggy doesn’t prevent diabetes; but good nutrition might. This is the message that the researchers promote in their article in Diabetes Care. Unfortunately, CNN couldn’t get past looking at the legs.