Here's the flipside to the story about foods that can help you sleep better: Eating a diet heavily composed of the "wrong" foods can interfere with your sleep.
That's the news from a new study conducted by scientists at the University of Minnesota and Minneapolis Veterans' Affairs Medical Center and presented at the annual meeting of the Society for the Study of Ingestive Behavior. What are the wrong foods in this case? A diet made of up high-fat foods may diminish the quality of your sleep as well as cause you to gain weight.
To investigate the effects of a high-fat diet on sleep, researchers put rats on a fatty-food diet for eight weeks. The rats, no surprise, gained weight. They then monitored the rats' 24-hour sleep-wake cycles and found that the animals' sleep cycles had changed for the worse:
•Rats who ate the high-fat diet for eight weeks slept more than rats on a regular diet
•These same rats also showed more fragmented sleep
•The extra sleep accrued by the high-fat-diet rats mostly occurred during the daytime.
Researchers likened this daytime sleeping among the high-fat diet-rats to the excessive daytime sleepiness that is common among people who are overweight or obese.
We know a lot -- and we're learning more all the time -- about the connections between sleep and weight. How lack of sleep causes hormonal changes in the body that stimulate appetite. How the timing of meals and sleep can affect daily calorie intake: Eating late in the day and the night-owl schedule that often accompanies late-in-the-day calorie consumption are more likely to lead to weight gain. How sleep can stimulate reward centers in the brain and impair brain function associated with impulse control and judgment. The result? A greater tendency to eat high-fat, high-sugar, often heavily processed foods.
So what's the connection between a high-fat diet and poor sleep quality? In discussing their results, researchers suggest the link may be a chemical in the brain that's involved in regulating both sleep and weight: orexin.