Effect of kiwifruit consumption on sleep quality in adults with sleep problems.
Level 4 - case-series / case-control
Uncontrolled single-arm before-and-after study without a parallel control group.
What was done
In an uncontrolled, self-controlled intervention trial, 24 adults (2 males, 22 females, aged 20 to 55 years) with self-reported sleep problems consumed 2 kiwifruits 1 hour before bedtime nightly for 4 weeks. Sleep parameters were evaluated before and after the intervention using the Chinese version of the Pittsburgh Sleep Quality Index (CPSQI), 3-day sleep diaries, and actigraphy watch monitoring.
What was found
After 4 weeks of nightly kiwifruit consumption: - Subjective CPSQI score decreased significantly by 42.4%. - Sleep onset latency decreased by 35.4%. - Waking time after sleep onset decreased by 28.9%. - Total sleep time increased by 13.4%. - Sleep efficiency increased by 5.41%.
Why it matters
This study provides preliminary evidence that evening kiwifruit consumption might help improve sleep onset, duration, and efficiency through dietary means.
Limits
The study had a very small sample size (n=24) that was overwhelmingly female (92%). There was no control or placebo group, making it impossible to separate the physiological effects of kiwifruit from placebo effects, natural symptom fluctuation, or non-specific behavioral routines. Baseline absolute values and variance measures were omitted from the abstract.
Cited by
- supports Consuming two to three kiwis before bed improves sleep quality in clinical studies.
- supports Studies show that kiwifruit and its constituent phytochemicals such as apigenin reduce cognitive function and arousal to promote sleep.