Objectives: To evaluate the effect of high and low glycaemic index drinks on children's sleep pattern.
Methods: Eight children underwent 3 nights of full polysomnography study, one familiarization and two test nights consecutively. On the test nights, 1 hour before bedtime, the children had a milk drink of either low or high GI in a random order. The glycaemic loads (GL) were 7.4 and 52.8 for low and high GI drink respectively.
Results: The mean of total arousal index in the first half of night after the high GI was greater than that of low GI drink. (12.9 +/- 4.6 vs. 9.9 +/- 2.2, P = 0.03). NREM arousal index in the first half of night after the high GI was also higher than that of low GI drink. (12.7 +/- 4.8 vs. 9.6 +/- 2.3, P = 0.05). Other sleep parameters did not show any significant difference in low GI and high GI diets.
Conclusion: NREM and total arousal indices were higher in those who consumed high GI drinks compared with low GI, one hour before sleep. It seems that the high quantity consumption of carbohydrates close to the bedtime is accompanied by frequent arousals and may affect the sleep quality.