I’ve been spending a lot of time catching up on sleep research in the last couple of weeks – and some of the new sleep studies out there are fascinating! I’m starting up a new blog series on “new sleep studies.” Expect several reports in the coming weeks, and then periodic updates going forward as cutting-edge new sleep studies become available.
Sleep and Eating
New research published online, ahead of May’s print issue of the journal Appetite, reports that the people with healthiest sleep patterns are also those with healthy diets. Researchers from the School of Medicine at the University of Pennsylvania explored the question of whether there are differences in diet between people who sleep short hours, longer hours, or “standard” hours of sleep.
Michael A. Grandner, first author and Instructor in Psychiatry (and member of the Center for Sleep and Circadian Neurology) at Penn, said in a statement reported by Medical News Today, “Although many of us inherently recognize that there is a relationship between what we eat and how we sleep, there have been very few scientific studies.”
Though it’s not a hard and fast number, as a general rule people who sleep between 7 and 8 hours a night tend to be in better health. The team looked for correlations between hours of sleep and foods consumed by studying data from the 2007 to 2008 National Health and Nutrition Examination Survey, or NHANES, which is a national survey conducted each year by the Centers for Disease Control and Prevention (CDC).
Said Grandner, “Overall, people who sleep 7 – 8 hours each night differ in terms of their diet, compared to people who sleep less or more. We also found that short and long sleep are associated with lower food variety.”
How Diet Relates to Sleep Patterns
The researchers put survey respondents in groups based on their survey answers: very short sleep of less than 5 hours/night, short sleep of 5 to 6 hours/night, standard or normal sleep of 7 to 8 hours/night, and long sleep of 9 or more hours/night. The NHANES data also contained detailed information about respondents’ daily diet and water intake, allowing the researchers to compare reported diet and sleep habits.
Calorie intake varied from group to group: Short sleepers tended to consume the most calories. Normal sleepers consumed less and very short sleepers even less; long sleepers consumed the least calories. Food variety, generally an indication of better overall health, was highest in the normal sleep group and lowest in the very short sleep group.
So those who don’t sleep enough tend to eat more calories but get them through only a few types of food, while healthy sleepers eat a more diverse diet but consume fewer overall calories. People with diverse diets but who don’t get as many daily calories tend to sleep extra hours. These findings have broad implications for health and sleep, but Grandner warns that the study doesn’t tell us how changing diet might change sleep – he says this is an important area for future research.