Are There Really Foods That Can Help You Sleep Better? The answer appears to be yes. In published in The American Journal of Clinical Nutrition by Ahmad Afaghi, Helen O’Connor, and Chin Moi Chow at the School of Exercise and Sport Science, Faculty of Health Sciences, The University of Sydney, in Sydney, Australia studied 12 healthy men who were 18-35 years old. The investigators studied the role of carbohydrates in sleep induction by examining the effect of glycemic index (GI) and meal time on sleep in healthy volunteers. The glycemic index, or GI, is a measure of the effects of carbohydrates on blood glucose levels. Carbohydrates that break down rapidly during digestion releasing glucose rapidly into the bloodstream have a high glycemic index; carbohydrates that break down slowly, releasing glucose gradually into the bloodstream, have a low glycemic index.
The men tried three varieties of cooked rice in their meals: plain rice, long-grain rice and jasmine rice – with steamed vegetables in tomato puree. Jasmine rice has a high glycemic index, while plain and long-grain rice have lower glycemic index. The researchers found that higher carbohydrates raised two brain chemicals involved in sleep, tryptophan and serotonin levels, making people sleepier. They also found that there was a reduction in sleep onset latency (SOL — the time it takes to fall asleep) by nine minutes in the group that had a high carbohydrate meal four hours before bed time. In addition, there was no difference between a meal consumed four hours before bedtime and one consumed one hour before bedtime. It’s important to note that these findings were only for healthy sleepers — meaning those who may have insomnia could have different results.