A study by the University of Granada, published in the European Journal of Nutrition, reveals a two-way relationship between dinner and sleep quality, which in turn influences subsequent breakfast choices. Researchers monitored obese individuals for 14 days, using accelerometers and sleep trackers, to observe real-life habits. The findings indicate that dinners high in calories, fat, cholesterol, protein, alcohol, red meat, or fried foods were linked to poorer sleep. Conversely, meals rich in carbohydrates, olive oil, and oily fish were associated with improved sleep quality. Furthermore, worse sleep quality correlated with less healthy breakfast habits, including higher calorie and sugar intake, and lower fiber consumption, especially for those who woke later or had fragmented sleep.