In order to live, we all must eat, sleep and breathe. The first two of those essential actions, however, impact each other in increasingly apparent ways. Looking at several separate recent studies, it appears sleep and weight manifest as a potentially viscious cycle.
Walter Reed Army Medical Center researchers analyzed the sleep patterns of 14 employees in an effort to understand the link between sleep and weight, and came up with intriguiging results.
“When we analyzed our data by splitting our subjects into ‘short sleepers’ and ‘long sleepers,’ we found that short sleepers tended to have a higher BMI, 28.3, compared to long sleepers, who had an average BMI of 24.5,” lead researcher Arn Eliasson, MD, explained at the American Thoracic Society conference in May. “Short sleepers also had lower sleep efficiency, experienced as greater difficulty getting to sleep and staying asleep.”
While they found a clear connection, they were unable to explain it, offering several possible reasons ranging from a lack of sleep causing a disruption in hunger hormones to stress leading to both poor sleep and overeating. However, a recent Merck study looking at circadian rhythm found a possible molecular explanation.
The Merck researchers discovered that mice given a drug to antagonize a certain calcium channel experienced increased sleep and became resistant to gaining weight. Additionally, the drug made obese rodents lose weight.
These two studies make it seem like a lack of sleep can make us fat, but a third study, presented last year by Brazilian researchers, offers the possibility that fat can cause a lack of sleep.
“We showed that an increased fat intake was associated with a lower percentage of REM sleep, a higher arousal index and apnea-hypopnea index, and a lower sleep efficiency,” said study author by Cibele Crispim. “These results showed that total fat intake and dinner fat intake seem to influence negatively the sleep pattern.”
All of these researchers agree on two things: that sleep and weight and/or nutrition are clearly linked, and that we still need much more research before we truly understand that connection and what we can do to optimize it.