Kiwi, the wonderfully, bright green fruit commonly used in fruit salad, may be added to the list of sleep-promoting foods. This fruit is high in antioxidants and fiber, packed with Vitamin C, and rich with potassium. Previous studies have shown that kiwi boosts our immune system, aids heart health and respiratory function. This “superfood” may now be adding sleep benefits to its intensive resume thanks to researchers at Taiwan’s Taipei Medical University.
Their study included 22 women and 2 men, between the ages of 20-55, who were having problems with disrupted sleep. For 4 weeks, the participants added eating 2 kiwis an hour before their bedtime to their routine. The researchers obtained data on the participants sleep by having them keep a sleep diary, answer questionnaires about sleep quality and wear wristwatches that measured sleep quantity and quality. The improved sleep findings were:
-Volunteers fell asleep more quickly, with a 35.4% decrease in the time it took to fall asleep after getting into bed.
-Volunteers slept more soundly, with a 28.9% decrease in the amount of time they spent awake during a sleep disruption.
-Volunteers reported improved sleep quality. Lower scores meant better sleep with a 42.4% decrease in reported bad sleep nights.
-Volunteers slept more overall, with total sleep time among them increasing by 13.4%
These significant improvements to participants’ sleep may be contributed to the high antioxidant properties and serotonin levels of kiwis. Research has indicated a relationship between sleep and antioxidants in the body; poor sleep is associated with low antioxidant levels. Getting more sleep has shown to be effective in restoring antioxidants levels but, the role rich-antioxidant foods play in promoting sleep is a new area to be explored.
Serotonin is a hormone that acts as a neurotransmitter and is involved in digestive and cardiovascular functions, learning and memory and it also regulates mood and appetite. When it comes to sleep, it helps us initiate sleep and stay asleep. Serotonin also appears to interact with melatonin, a well known sleep-inducing hormone. This relationship indicates that is essential to our body’s natural 24-hour clock, regulating our sleep-wake cycle.
Kiwi may be added to the list of foods to help to you, but there is no need to rush to the grocery store after one study. Try adding known sleep-boosting foods to diet that are rich in magnesium, potassium and calcium such as dark leafy greens, bananas, nuts, whole grains and soy. Eating a healthier diet is a sure way to sleep better every night!