Claire E. Kim, lead author of the study at the Department of Preventive Medicine at Seoul National University College of Medicine, said in a statement: “We observed a potential gender difference between sleep duration and metabolic syndrome, with an association between metabolic syndrome and long sleep in women and metabolic syndrome and short sleep in men.”
But the study stopped short of finding a cause and effect tie between sleep and metabolic syndrome. Now, more research is needed to identify the biological mechanisms behind this association. Scientists believe it could be due to a shift in hormones that boost the appetite or those who get fewer hours of sleep being less active.
The new findings follow a separate study which linked too much or too little sleep with developing dementia. A team of researchers at Kyushu University in Japan found the risk of dementia and early mortality was “significantly greater” in those who slept fewer than five hours or more than 10 hours, compared to those who sleep between five to 6.9 hours.