Higher daytime intake of fruits and vegetables predicts less disrupted nighttime sleep in younger adults

Abstract

Background: Higher-quality diets are associated with better sleep quality in observational studies. However, a better understanding of this association is needed given that dietary modifications could represent a novel and natural approach to achieve better sleep. Objective: To examine how daytime dietary intakes influence sleep quality on the following night using multiple days of self-reported diet monitoring and objective sleep measured under free-living conditions. Methods: Participants were younger US adults with average habitual sleep duration between 7 and 9 hours per night. Diet was assessed using the Automated Self-Administered 24-Hour Dietary Assessment Tool. Sleep was measured using wrist actigraphy. Sleep fragmentation index was used for objective assessment of sleep quality. Results: Thirty-four participants (age: 28.3 ± 6.6 years, BMI: 24.1 ± 3.9 kg/m2, 82.3% males, 50.0% racial/ethnic minority) provided 201 paired diet-sleep data. Greater daytime intakes of fruits and vegetables (β-coefficient (SE) = −0.60 (0.29), P = .038) and carbohydrates (−0.02 (0.007), P = .022), but not added sugar (P = .54), were associated with lower sleep fragmentation index. Trends toward associations of higher intakes of red and processed meat (P = .10) with more disrupted sleep, as well as higher fiber (P = .08) and magnesium (P = .09) intakes with less disrupted sleep, were observed. Conclusions: Higher daytime intakes of fruits and vegetables and carbohydrates that align with a healthy diet were associated with less disrupted nighttime sleep. A 5-cup increase (from no intake) in fruits and vegetables, meeting dietary recommendations, was associated with 16% better sleep quality. These findings suggest that diets rich in complex carbohydrates, fruits, and vegetables may promote better sleep health. Clinical trial registry: NCT03663530 and NCT03257137