Race and short sleep duration increase the risk for obesity

June 8, 2009

Race significantly influences the risk of obesity conferred by short sleep duration, with blacks having a greater risk than whites.

Results indicate that short sleep was associated with obesity, with the adjusted odds ratios for black Americans (1.78) and white Americans (1.43) showing that blacks had a 35 percent greater risk than whites of obesity associated with short sleep. The prevalence of obesity (body mass index of 30 or higher) was 52 percent for blacks and 38 percent for whites. The prevalence of short sleep (5 hours or less) was 12 percent for blacks and eight percent for whites.

According to lead author Girardin Jean-Louis, PhD, associate professor at the SUNY Downstate Medical Center at the Brooklyn Health Disparities Research Center in New York, the findings suggest that short sleep time may be a contributor to the obesity crisis. Previous studies have established that individuals who sleep for less than seven hours per night may be at a greater risk for becoming obese.

"Compared to white Americans, black Americans had a greater prevalence of short sleep (five hours of sleep per night or less) and a greater prevalence of obesity. Both black and white Americans who were obese tended to have short sleep duration," said Jean-Louis.

The study analyzed data from 29,818 individuals who completed the 2005 National Health Interview Survey, a cross-sectional household interview survey using multistage area probability and design. Data were collected from all 50 states and Washington, D.C. Participants were between the ages of 18 and 85 years; 85 percent of the sample was white and 15 percent was black; 56 percent of participants were women.

According to the authors, black Americans may have an increased risk for obstructive sleep apnea and diabetes, both of which are associated with obesity.

Source: American Academy of Sleep Medicine (news : web)