Older Americans have nearly double the prevalence of Type-2 diabetes than their English counterparts. What might explain this disparity of health between Yanks and Brits? Past research has looked at age, smoking, socioeconomic status, and Body Mass Index (BMI) – common risk factors for type-2 diabetes. Alas, none of these factors can be considered the main culprit in the apparent health disadvantage among Americans quite like our waist size according to a new study recently published in the Journal of Epidemiology and Community Health.
A great deal of evidence points to “central obesity” — or large amounts of belly fat — as a risk factor for diabetes. Fat cells in the abdomen are more likely to be associated with insulin resistance and diabetes than fat cells stored elsewhere. A team of researchers in both countries looked at data from interviews, physical exams, and laboratory results from 4,570 Americans and 6,888 Brits. These subjects were both men and women between the ages of 52 and 85 years. Since prior studies have not looked closely at waist circumference, the experts checked if it may be a diabetes risk factor. Waist circumference over 35 inches in women and over 40 inches in men is considered a risk factor for many chronic diseases. For Asians, the cutoffs are even lower – 31 inches for women and 35 inches for men.
The researchers took physical measurements, blood samples, and health histories from all participants. Overall, prevalence of diabetes among the Brits was 7 percent for women and 11 percent for men, and among the Americans, the rates were 14 percent for women and 16 percent for men. Average BMI was not significantly different between Brits and Americans.
After adjusting for factorsl, waist circumference accounted for 38% of difference in diabetes prevalence among the men and nearly 3/4 of the difference in women. Interestingly, 56 percent of British women and 41 percent of British men had waist circumferences that exceeded 35 inches and 40 inches, respectively, compared to 69 percent of American women and 56 percent of American men. According to the researchers, some possible reasons for this difference include diet quality and levels of physical fitness. They suggest that waist circumference measurements should be used in future studies of other chronic diseases and disparities between various countries.
Because this study was conducted on non-Hispanic whites only, further studies are needed to determine if similar conclusions can be drawn for other races. Nonetheless, this study is a first step toward understanding that our waistlines affect more than the pant sizes we buy.