Carbs May Help You Fall Asleep Faster
Biggest Benefit From Starchy Carbohydrates, Study Shows
WebMD News Archive
Feb. 14, 2007 -- To fall asleep faster, you might want to consider eating
starchy carbohydrates before bedtime.
That's according to an Australian study published in The American Journal
of Clinical Nutrition.
Carbs which quickly raise blood sugar (those with a high glycemic index) may
hasten sleep, especially when eaten four hours before bedtime, the researchers
Such carbs may boost tryptophan and serotonin, two brain chemicals involved
in sleep, the study suggests.
The University of Sydney's Chin Moi Chow, PhD, and colleagues studied 12
healthy men who were 18-35 years old.
The men, who had no sleep problems, spent three nights at the researchers'
sleep lab. They took one week off between stays at the lab.
Step No. 1: Eat
First, the men fasted for five hours. Afterwards, the researchers served
them a meal at the sleep lab.
The basic menu -- rice with steamed vegetables in tomato puree -- was the
same each night. But the type of rice and mealtime varied.
One meal included jasmine rice and was served one hour before bedtime.
Another meal featured jasmine rice and was served four hours before
The third meal included long-grain rice and was also served four hours
The researchers changed the rice to measure the effects of carbs with high
and low glycemic indices. Jasmine rice has a high glycemic index; long-grain
rice has a lower glycemic index.
They changed the meal schedule to see whether timing tweaked the carbs'
Step No. 2: Sleep
The men tried all three meals over the course of the study, eating one meal
per night. They were free to go to bed whenever they wanted.
The researchers timed how long it took the men to fall asleep once in
The men fell asleep fastest after eating the jasmine rice meal four hours
before bedtime. It took them nine minutes, on average, to fall asleep that
The men took nearly 15 minutes, on average, to fall asleep after eating the
jasmine rice meal one hour before bedtime.
They were slowest to fall asleep after eating the long-grain rice meal four
hours before bedtime, taking nearly 18 minutes, on average, to fall asleep.
The meals had no other effect on the men's sleep, the study shows.
Chow's team doesn't know exactly how carbs with a high glycemic index affect
Although the researchers speculate such carbs raise tryptophan and serotonin
levels, making people sleepier, they didn't measure the levels of the brain
chemicals in the men.
Adding protein to the meal might change the results, Chow's team notes.