A recent study published in the journal Nature Health suggests that diets rich in nutrient-dense plant foods such as fruits, vegetables, whole grains, beans, nuts, and olive oil may contribute to improved sleep quality. Researchers analyzed extensive data collected over several years from thousands of participants enrolled in the Human Phenotype Project, a large-scale digital health study involving some 28,000 individuals.

The study investigated how various dietary factors influenced multiple aspects of sleep, including its duration, depth, and restorative quality. Among 32 dietary variables examined, seven were found to be significantly associated with sleep outcomes. Higher intake of fiber-rich plant foods was linked to increased deep sleep and rapid eye movement (REM) sleep, stages essential for memory consolidation and overall brain health. Participants with diets high in minimally processed plant foods such as beans, lentils, nuts, and vegetables also exhibited lower nighttime heart rates, a marker of healthy rest and recovery.

The researchers further assessed the dietary phytochemical index, which measures the proportion of calories derived from plant compounds with antioxidant and anti-inflammatory properties, such as beta-carotene, lycopene, and resveratrol. Diets high in phytochemicals correlated with more deep and REM sleep, reduced light sleep, and decreased nighttime heart rate.

One notable finding was that consuming heavier evening meals was associated with slightly longer sleep durations. However, this increase in sleep time came with elevated nighttime heart rates, suggesting that the additional sleep may not be as restorative. While many experts recommend lighter dinners to prevent acid reflux and sleep disturbances, the study indicates that a larger meal not consumed immediately before bedtime might extend total sleep time, though potentially at the expense of sleep quality.

Experts not involved in the study remarked on its rigorous methodology and findings. Marie-Pierre St-Onge, a professor of nutritional medicine at Columbia University Irving Medical Center, noted that prioritizing plant-based foods rich in fiber and phytonutrients could be beneficial for individuals seeking better sleep. She highlighted that fruits and vegetables contain compounds that interact with GABA receptors in the brain, promoting relaxation and facilitating sleep onset. Additionally, a diet emphasizing plant foods might support a gut microbiome that produces short-chain fatty acids, which influence neurotransmitter activity linked to sleep regulation.

St-Onge, who authored the 2025 book "Eat Better, Sleep Better," advocates for dietary patterns aligned with these findings without necessarily eliminating animal products. Her recommendations include meals that combine plant-based ingredients with moderate amounts of protein, such as spinach and salmon quiche for breakfast, a turkey and black bean burrito bowl for lunch, and garlic shrimp paired with fresh salads for dinner.

This study adds to mounting evidence supporting the role of plant-forward diets in sleep improvement and underscores the complex relationship between nutrition and sleep health.