Eating five cups of fruit and vegetables during the day may significantly improve sleep quality that same night, according to new research.
The study is the first to show a time-based link between what people eat during the day and their objectively measured sleep that night.
Sleep fragmentation – when a person wakes frequently or moves between deep and light sleep – is known to affect memory, mood, learning and heart health. Previous studies have also shown that poor sleep can lead to diets higher in sugar and fat.
Researchers from Columbia and the University of Chicago found that going from a diet with no fruit to one that includes five cups a day led to more sound, uninterrupted sleep.
Sleep expert Dr Esra Tasali is a co-author of the study.
The researcher said: “It’s remarkable that such a meaningful change could be observed within less than 24 hours.
“Dietary modifications could be a new, natural and cost-effective approach to achieve better sleep.”
The study involved healthy young adults who reported their food intake using an app and wore wrist monitors to objectively track their sleep patterns.
Researchers specifically measured sleep fragmentation – how often participants woke up or moved between deep and light sleep overnight.
Each day’s diet was linked to changes in the following night’s sleep.
Those who ate more fruits and vegetables experienced deeper and less interrupted sleep.
Participants who consumed healthier carbohydrates such as whole grains also appeared to sleep better.
The researchers estimated that those eating the recommended five cups of fruit and vegetables per day could see a 16 per cent improvement in sleep quality compared to those who ate none.
Dr Tasali said: “Sixteen per cent is a highly significant difference,” said
The team now hopes to carry out further research in more diverse populations to explore the mechanisms behind the impact of diet on sleep.
In the meantime, they recommend a diet rich in complex carbohydrates, fruit and vegetables as a long-term strategy for improving sleep.
