Both a large belly and obesity can increase the risk of developing restless legs syndrome (RLS), a common sleep disorder characterized by an irresistible urge to move your legs, a new study has shown.
The research is published in the April 7, 2009, print issue of Neurology, the medical journal of the American Academy of Neurology.
For the study, researchers questioned 65,554 women and 23,119 men, all of whom were health professionals who took part in the Health Professionals Follow-Up Study or the Nurses' Health Study II. None of the participants had diabetes, arthritis or were pregnant. Of the groups, 6.4 percent of the women and 4.1 percent of the men were identified as having RLS.
The research found men and women with a body mass index (BMI) score over 30 were nearly one-and-a-half times more likely to have RLS than people who were not obese.
In addition, people who were in the top 20 percent of the group for highest waist circumference were more than one-and-a-half times more likely to have RLS than the bottom 20 percent of the group with the lowest belly size. The results were the same regardless of age, smoking, use of antidepressants or anxiety.
"These results may be important since obesity is a modifiable risk factor that is becoming increasingly common in the U.S.," said study author Xiang Gao, MD, PhD, with the Harvard School of Public Health in Boston.
"More research is needed to confirm whether obesity causes RLS and whether keeping a low BMI score and small waist size could help prevent RLS," the expert added.
Gao says some studies suggest that obese people have lower dopamine receptor levels in the brain.
"Since decreased dopamine function is believed to play a critical role in RLS as well, this could be the link between the two," Gao said.
Dopamine is a chemical naturally produced by the body that transmits signals between nerve cells.