Anyone who has overeaten at dinner knows that diet impacts sleep quality, but recent studies indicate that this influence can be even more significant. A study published in July in the Journal of Internal Medicine established a correlation between greater diversity of gut microbiota and better quality sleep. This investigation demonstrated that consuming capsules with beneficial bacteria managed to reduce chronic insomnia symptoms by 13.9% after only one month of continuous treatment.
In line with this, an editorial published in 2025 in the journal Nutrients compiled various evidence on the link between eating habits and sleep quality. This article highlights studies proving that following healthy dietary patterns contributes to a satisfying night's rest. Furthermore, a survey conducted with 570 medical students, also published in the same journal, showed that meal organization helped decrease the need for sleeping medications.
The bidirectional relationship between diet and sleep
Neurophysiologist Letícia Azevedo Soster, from Einstein Israelite Hospital, summarizes this connection by stating that 'diet and sleep mutually influence each other.' She explains that those who eat improperly may experience fragmented sleep. Consequently, this person tends to seek foods rich in calories and rapidly absorbed carbohydrates to get through the next day. Thus, the relationship is mutual: deterioration in one factor generally leads to deterioration in the other, and vice versa.
To ensure adequate rest, it is necessary to go beyond simple sleep hygiene; circadian hygiene must be implemented by incorporating healthy practices into the daily routine. According to the doctor, 'having a good sleep routine depends on everything a person does during the day and what allows the body, when going to bed, to fall asleep and maintain the continuity of that sleep.' She details that establishing fixed meal times, maintaining a balanced diet, and respecting the amount of sleep required by the body are effective strategies for synchronizing biological rhythms.
Dietary recommendations to optimize rest
A practical recommendation is to have dinner earlier, maintaining a fasting period of at least two hours before going to bed. It is advisable to avoid slow-digesting foods, such as red meat and excessively fatty dishes, as they require additional metabolic effort at a time meant for rest.
It is equally important to moderate the consumption of stimulating beverages, including coffee, sodas, and energy drinks, even in the afternoon. Letícia Soster clarifies that, because they are stimulants, these drinks prevent the body from recognizing signs of fatigue and significantly harm the onset of sleep, a key parameter in insomnia assessment.
Alcohol should also be consumed with caution. Although it can provide a false sense of relaxation and facilitate initial falling asleep, it causes later micro-awakenings and interrupts REM sleep, a phase essential for brain cleansing and where dreams occur, according to nutritionist Gabriella Dias, also affiliated with Einstein.
Natural allies for restorative sleep
Among beneficial foods, sources of tryptophan stand out, such as dairy products, nuts, and seeds. However, Dias emphasizes that no single food solves insomnia; the benefit comes from a healthy dietary pattern combined with good habits. She cites the 2025 Nutrients editorial, which points out that a diet rich in fish, fruits, vegetables, and milk notably improves sleep quality. To complete the ideal formula for nighttime relaxation, it is suggested to have a nutritious breakfast and concentrate most of the calories at the beginning of the day, along with an early dinner.